Hyperventilation and reduced cerebral blood flow velocity can occur in postural tachycardia syndrome (POTS). We studied orthostatically intolerant patients, with suspected POTS, with a chief complaint of upright dyspnea. On the basis of our observations of an immediate reduction of cerebral blood flow velocity with orthostasis, we hypothesize that the resulting ischemic hypoxia of the carotid b...

Variants of postural tachycardia syndrome (POTS) are associated with increased ["high-flow" POTS (HFP)], decreased ["low-flow" POTS (LFP)], and normal ["normal-flow" POTS (NFP)] blood flow measured in the lower extremities while subjects were in the supine position. We propose that postural tachycardia is related to thoracic hypovolemia during orthostasis but that the patterns of peripheral blo...

 As a IP telephony protocol, the SIP is gaining increasing popularity. There is yet POTS(Plain Old Telephone Service) line as the existing subscriber line. The Megaco/H.248 may be used for call between the POTS line and SIP. So, it is needed that method for interworking between Megaco/H.248 and SIP. In this paper, we propose the implementation of Residential Media Gateway Prototype in Interwor...

A major goal of the Telecommunications Act of 1996 is to promote competition in both the local exchange and long distance wireline markets. In section 271 Congress permitted the Bell Operating Companies (BOCs) to enter the long distance market only if they demonstrate to the FCC that they have complied with the market-opening requirements of section 251. This paper examines the logic behind sec...

cell expansion and cell division are two main processes in plant growth and development. expansin proteins play a role key in cell expansion. these non-enzyme proteins involve in many growth and developmental processes. this protein affects drought tolerance. atexpb2 gene belongs to these proteins family. atexpb2 gene mainly expresses in the root tissue. in this study the expb2 gene, that was i...

Postural tachycardia syndrome (POTS) is a heterogeneous disorder of the autonomic nervous system, consisting of orthostatic intolerance and an increase in heart rate of more than 30 bpm within 10 min of standing or head-up tilt [1]. Human Papillomavirus Quadrivalent Vaccine, Gardasil, has been approved for prevention of cervical cancer in women, aged 9–26. We describe a 20-year-old woman who de...

BACKGROUND Postural tachycardia syndrome (POTS) is related to defective peripheral vasoconstriction of dependent extremities with redistributive hypovolemia. METHODS AND RESULTS To test whether enhanced microvascular filtration produces leg enlargement, we studied 12 patients 13 to 19 years of age with POTS and defective leg vasoconstriction and 13 age-matched healthy control subjects, with s...

Purpose Postural orthostatic tachycardia syndrome (POTS) is a form of orthostatic intolerance characterized by an increased heart rate upon transition from supine to standing, and head-up tilt without orthostatic hypotension. Its etiology is multifactorial, and no clear cause has been identified. Common symptoms include light-headedness, blurred vision, weakness, cognitive difficulties, and fat...