Suppression of pain sensation caused by millimeter waves: a double-blinded, cross-over, prospective human volunteer study

We conducted a double-blinded, randomized, cross-over, prospective trial to evaluate the pain relief effect of millimeter waves (MW) under experimental conditions. The cold pressor test was used as a model of tonic aching pain. Twelve healthy male volunteers were exposed to an active medical MW generator and to a disabled sham generator with at least 24 h between exposures. Characteristics of continuous-wave electromagnetic output from the active generator were: wavelength 7.1 mm, incident power density 25 +/- 5 mW/cm2, and duration of exposure 30 min. MW produced a significant (P < 0.05) suppression of pain sensation, with an average 37.7% gain in pain tolerance and a 49.3% increase in pain sensitivity range (the latter being the difference between pain tolerance and pain threshold values). Of the 12 volunteers, 7 (58.3%) reacted to the active MW generator with an increased pain tolerance, and the individual reactions varied from 120% to 315% comparison with their own preexposure levels. MW therapy can potentially be used as a supplementary or alternative treatment for pain relief. Implications: Pain management is still a significant medical problem. In a double-blinded, experimental setting, we confirmed that low-intensity millimeter wave therapy can reduce pain sensitivity in healthy human volunteers and can potentially be used as a supplementary or alternative treatment for pain relief.     

Clinical spectrum and diagnostic difficulties of infantile ponto-cerebellar hypoplasia type 1

We present the clinical and histopathological features and the diagnostic difficulties encountered in five children affected by a motor neuron disorder other than spinal muscular atrophy. Investigations performed suggested the diagnosis of ponto-cerebellar hypoplasia type 1 (PCH-1). Severe respiratory difficulty was present at birth in two of these children; hypotonia, arthrogryposis, microcephaly and nystagmus were present in all. Early and progressive bulbar involvement with swallowing difficulties and stridor was also a common feature in these infants. Severe cognitive delay was invariably present. Brain magnetic resonance imaging showed ponto-cerebellar hypoplasia in four children while striking atrophy of the cerebellar vermis and cerebellar hemispheres were present in the fifth child. Electrophysiological and pathological investigations of proximal muscles performed at presentation in all these children were not conclusive, while the post-mortem studies, or the study of distal muscles during life, showed a clear neurogenic picture. Genetic studies excluded involvement of the SMN gene, or of other genes located on chromosome 5q, confirming that ponto-cerebellar hypoplasia type 1 is a different entity from typical proximal spinal muscular atrophy.     

Echocardiography overestimates left ventricular mass in hemodialysis patients relative to magnetic resonance imaging

Echocardiography overestimates left ventricular mass in hemodialysis patients relative to magnetic resonance imaging. BACKGROUND: Left ventricular hypertrophy (LVH) is a common finding and a strong adverse prognostic factor in patients with chronic renal failure. An accurate method of measuring left ventricular mass (LV mass) is therefore a prerequisite in the management of these patients. Recent evidence has suggested that echocardiography overestimates LV mass in patients with essential hypertension, and this error increases with increasing LV mass. METHODS: We studied 35 patients on maintenance hemodialysis within 24 hours of their last dialysis. LV mass was measured by both echocardiography and magnetic resonance imaging (MRI) performed less than three hours apart. Clinic and ambulatory blood pressure (ABPM), resting echocardiogram, and blood sampling were performed at the same visit. RESULTS: Thirty-two patients had results from both methods. Clinic blood pressure, ABPM, and QT dispersion all correlated with LV mass, with a stronger correlation observed for MRI values. Intraobserver and interobserver variability were significantly greater for echocardiography (although similar to other published data). Comparing the two methods, the difference in LV mass values (echo minus magnetic resonance) increased in a linear fashion with an increasing mean mass and chamber diameter. CONCLUSIONS: Echocardiography significantly overestimates LV mass relative to MRI in the presence of LVH and dilation. This overestimation is the result of assumptions made in the calculation of mass from echocardiography M-mode images, which are invalid when LV geometry is abnormal. This error is therefore amplified in dialysis patients, the majority of whom have LVH and in whom intravascular volume is constantly changing.     

National health expenditures, 1998

In 1998, national health care expenditures reached $1.1 trillion, an increase of 5.6 percent from the previous year. This marked the fifth consecutive year of spending growth under 6 percent. Underlying the stability of the overall growth, major changes began taking place within the Nation's health care system. Public payers felt the initial effects of the Balanced Budget Act of 1997 (BBA), and private payers experienced increased health care costs and increased premium growth.     

Business, households, and government: health spending, 1994

During the 1990s, growth in health care costs slowed considerably, helping to lessen the spending strain on business, government, and households. Although cost growth has slowed, the Federal Government continues to pay an ever-increasing share of the total health care bill. This article reviews important health care spending trends, and for the first time, provides separate estimates of the employer and employee share of the premium costs for employer-sponsored private health insurance. This article also highlights some of the emerging trends in the employer-sponsored insurance market, including managed care, cost-sharing, and employment shifts.     

Hospitals overseas: keeping costs down

Britain is far from alone in its attempts to curb the capital costs of new hospitals. David Cowan, leader of the hospitals research group in the South African National Building Research Institute at Pretoria, describes in this paper, based on one originally presented to an IHF congress, how his country has tried to meet the problem.     

An autoradiographic study of the organization of the efferent connections of the hippocampal formation in the rat.

The efferent connections of the hippocampal formation of the rat have been re-examined autoradiographically following the injection of small quantities of 3H-amino acids (usually 3H-proline) into different parts of Ammon's horn and the adjoining structures. The findings indicate quite clearly that each component of the hippocampal formation has a distinctive pattern of efferent connections and that each component of the fornix system arises from a specific subdivision of the hippocampus or the adjoining cortical fields. Thus, the precommissural fornix has been found to originate solely in fields CA1-3 of the hippocampus proper and from the subiculum; the projection to the anterior nuclear complex of the thalamus arises more posteriorly in the pre- and/or parasubiculum and the postsubicular area; the projection to the mammillary complex which comprises a major part of the descending columns of the fornix has its origin in the dorsal subiculum and the pre- and/or parasubiculum; and finally, the medial cortico-hypothalamic tract arises from the ventral subiculum. The lateral septal nuclei (and the adjoining parts of the posterior septal complex) constitute the only subcortical projection field of the pyramidal cells in fields CA1-3 of Ammon's horn. There is a rostral extension of the pre-commissural fornix to the bed nucleus of the stria terminalis, the nucleus accumbens, the medial and posterior parts of the anterior olfactory nucleus, the taenia tecta, and the infralimbic area, which appears to arise from the temporal part of field CA1 or the adjacent part of the ventral subiculum. The projection of Ammon's horn upon the lateral septal complex shows a high degree of topographic organization (such that different parts of fields CA1 and CA3 project in an ordered manner to different zones within the lateral septal nucleus). The septal projection of "CA2" and field CA3 is bilateral, while that of field CA1 is strictly unilateral. In addition to its subcortical projections, the hippocampus has been found to give rise to a surprisingly extensive series of intracortical association connections. For example, all parts of fields CA1, CA2 and CA3 project to the subiculum, and at least some parts of these fields send fibers to the pre- and parasubiculum, and to the entorhinal perirhinal, retrosplenial and cingulate areas. From the region of the pre- and parasubiculum there is a projection to the entorhinal cortex and the parasubiculum of both sides. That part of the postsubiculum (= dorsal part of the presubiculum) which we have examined has been found to project to the cingulate and retrosplenial areas ipsilaterally, and to the entorhinal cortex and parasubiculum bilaterally.     

National health accounts: lessons from the U.S. experience

The national health accounts (NHA) are the framework within which type of services and sources of funding for health care expenditures are measured. NHA, devised to portray the structure of health care delivery and financing in the United States, provide essential information necessary for the formulation of public health policy and for international comparison. In this article, the authors describe the importance of the NHA nationally and internationally, and provide a blueprint of the definitions, sources, and methods used to create this system of NHA in the United States.