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PubMed2004

[Repair of the penial injury in patients inflicted by high-voltage electrical injury].

OBJECTIVE: To explore the repair and reconstruction of penial defect in patients inflicted by high-voltage electrical injury. METHODS: Among one hundred and fifty three patients inflicted with high-voltage electrical injury, 6 suffered from penial injury (including 3 with necrosis of whole penis, 1 with partial necrosis of penis, 1 with partial necrosis of penial shin and 1 with necrosis of entire skin of penis) were enrolled in the study. The penis was repaired by direct suture of the residual skin following excision of necrotic skin in one case, by skin grafting in two case, by scrotum skin flap transplantation in 3 cases. RESULTS: The appearance and function of the penis in three cases were satisfactory, and the result was also satisfactory in one patient who underwent reconstructive operation at late post injury stage. The penis was totally lost in 2 patients. CONCLUSION: The skin necrosis of penis after high-voltage injury could be repaired with scrotum skin flap. Total necrosis of the penis could be reconstructed with abdominal skin flap.

Adolescent↗
PubMed1993

Treatment of facial muscles affected by Bell's palsy with high-voltage electrical muscle stimulation.

OBJECTIVE: This report discusses high-voltage electrical muscle stimulation and chiropractic manipulation used to treat two patients who suffered from Bell's palsy. CLINICAL FEATURES: Case A: A 15-yr-old with left sided facial palsy was seen 2 days after the onset of symptoms. Upon observation, the left upper and lower eyelids were drooping and the left eye had excessive tearing. Motion palpation indicated multiple fixations in the cervical spine. Laboratory studies showed a microcytic anemia. A clinical diagnosis of Bell's palsy (House-Brackmann Grade V) and microcytic anemia was made. Case B: A 17-yr-old with left sided facial palsy was seen 8 days after onset of symptoms. Upon observation, the patient showed left sided facial paralysis and an inability to close the left eye completely. Motion palpation indicated multiple fixations in the cervical spine. A clinical diagnosis of Bell's palsy (House-Brackmann Grade V) was made. INTERVENTION AND OUTCOME: Both patients were treated with high-voltage pulsed galvanic current at 80 peaks/sec with a 7-inch hand-held held probe for 10 min each visit. In addition, the cervical spine fixations were mobilized using chiropractic manipulation. Case A was resolved after 6 wk of treatment and case B was resolved after 3 wk of treatment. CONCLUSION: Both patients benefited from these procedures with complete resolution of symptoms. The techniques outlined should be used at an early stage to accelerate progress toward normal facial muscle function.

Adolescent↗
PubMed2001

[Morphological changes and quantitative DNA analysis of Schwann cells in peripheral nerves after high voltage electrical injury].

OBJECTIVE: To explore the characteristics and the mechanism of the injury of Schwann cells and nerve fibres of the peripheral nerves inflicted by high voltage electricity. METHODS: Rabbits injured by high voltage electricity were employed as the model. Thirty rabbits were randomly divided into control (9) and experimental (21) groups. The dynamic quantitative DNA analysis and the change of the morphology and structure of the sciatic nerve were observed with LM and EM on 0, 3, 7, 10, 14 and 21 postburn days (PBDs), respectively. RESULTS: There was continuous degeneration of the axon and medullary sheath of sciatic nerve tissue and its neogenesis was inhibited. The DNA synthesis in Schwann cell initiated on 3 postburn day (PBD). The distribution of the current was heterogeneous on the cross section of peripheral nerve fibres. CONCLUSION: The obvious features of peripheral nerve injured by high voltage electricity included delayed initiation of the DNA synthesis of Schwann cell and the secondary necrosis and inhibition of neogenesis process of Schwann cell.

Animals↗
PubMed2005

Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study.

OBJECTIVE: To determine whether there is an association between distance of home address at birth from high voltage power lines and the incidence of leukaemia and other cancers in children in England and Wales. DESIGN: Case-control study. SETTING: Cancer registry and National Grid records. SUBJECTS: Records of 29 081 children with cancer, including 9700 with leukaemia. Children were aged 0-14 years and born in England and Wales, 1962-95. Controls were individually matched for sex, approximate date of birth, and birth registration district. No active participation was required. MAIN OUTCOME MEASURES: Distance from home address at birth to the nearest high voltage overhead power line in existence at the time. RESULTS: Compared with those who lived > 600 m from a line at birth, children who lived within 200 m had a relative risk of leukaemia of 1.69 (95% confidence interval 1.13 to 2.53); those born between 200 and 600 m had a relative risk of 1.23 (1.02 to 1.49). There was a significant (P < 0.01) trend in risk in relation to the reciprocal of distance from the line. No excess risk in relation to proximity to lines was found for other childhood cancers. CONCLUSIONS: There is an association between childhood leukaemia and proximity of home address at birth to high voltage power lines, and the apparent risk extends to a greater distance than would have been expected from previous studies. About 4% of children in England and Wales live within 600 m of high voltage lines at birth. If the association is causal, about 1% of childhood leukaemia in England and Wales would be attributable to these lines, though this estimate has considerable statistical uncertainty. There is no accepted biological mechanism to explain the epidemiological results; indeed, the relation may be due to chance or confounding.

Adolescent↗
PubMed1998

[No increase in cancer incidence due to high-voltage cables in Odijk].

OBJECTIVE: To determine the incidence of cancer in Odijk and the connection if any of the occurrence of cancer with the presence of a high-voltage cable constructed there in the fifties. DESIGN: Descriptive. SETTING: Public Health Services, South-East Utrecht, the Netherlands. METHOD: Data on the numbers of new cancer patients in Odijk over the period 1985/'96 were obtained from general practitioners, from the Integral Cancer Centre Mid-Netherlands (IKMN) and from the Foundation Dutch Study Group Leukaemia in Children. The classifications were according to age and to distance from the home to the high-voltage cable. The electric and magnetic field strengths in dwellings situated less than 28 m from the cable were calculated. RESULTS: Cancer was diagnosed in 131 patients in the period 1985/'96, 127 adults and four children. The cases in 3 of 4 children occurred in the period 1993/'96. Over the period 1990-1994, the registered cancer incidence did not deviate from the expected incidence in the IKMN region, nor from the mean incidence in the Netherlands. Neither for adults nor for children was a relationship found between cancer and living in the vicinity of the high-voltage cable. The exposure to the electric field of persons living in houses near the cable was maximally 7%, and exposure to the magnetic field maximally 6.5% of the maximal liminal values applied in the Netherlands on recommendation of the Health Council. CONCLUSION: No relationship existed between development of cancer and the presence of a high-voltage cable.

Adolescent↗
PubMed2004

Residential exposure to overhead high-voltage lines and the risk of testicular cancer: results of a population-based case-control study in Hamburg (Germany).

BACKGROUND: In a population-based case-control study we examined the association between residential exposure to overhead high-voltage lines and testicular cancer. METHODS: We recorded the residential biography of cases with testicular cancer identified by the Hamburg Cancer Registry and of controls that were randomly selected from the mandatory registry of residents in Hamburg. The study included 145 incident cases between 15 and 69 years of age, diagnosed between 1995 and 1997, and 313 controls, matched for age in 5-year strata. In model A, exposure was defined by distance (ever vs never). Model B took into account residence time and the inverse distance from the nearest high-voltage line. It distinguished between low and high exposure, the never exposed persons serving as a reference group. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated by unconditional logistic regression. For men below the age of 40 years and men aged 40 years and over separate analyses were carried out. RESULTS: Within a corridor of 100 m the prevalence of exposure to high-voltage lines in Hamburg was 6.9% in cases and 5.8% in controls (OR=1.3; 95% CI=0.56-2.80). In the more complex model B we found an OR of 1.2 (95% CI=0.60-2.47) for low exposure and 1.7 (95% CI=0.91-3.32) for high exposure. Younger men show slightly increased risks in both models. CONCLUSIONS: In all, residential exposure to high-voltage lines did not seem to be a major risk factor for testicular cancer in our study. Yet, the fact that risks for men below the age of 40 years were slightly increased in both exposure models deserves further attention.

Adolescent↗
PubMed2004

Compact, high voltage power supply for the lab-on-a-chip.

The design, construction and operation of a simple, inexpensive and compact high voltage power supply (HVPS) for use in conjunction with a simple cross capillary electrophoresis microchip is presented. The microchip HVPS utilizes a single high voltage power supply (15 kV), a voltage-divider network, to give the voltages necessary to operate a gated injection valve, and two high voltage relays for switching between the open and closed gate sequences of the injection. In order to accommodate the application of different simple cross microchip dimensions, a set of equations for defining the resistor network and ensuring proper gate performance are presented.

Electric Power Supplies↗
PubMed2004

[Application of digital subtraction angiography and type B ultrasonography in the evaluation of vascular injury in patients with high voltage electrical injury].

OBJECTIVE: To compare the difference between digital subtraction angiography (DSA) and type B ultrasonography in the evaluation of vascular injury in patients inflicted with high voltage electrical injury. METHODS: Nineteen patients with high voltage electrical injury of upper limbs were enrolled in the study as burn group, and another 12 healthy volunteers as controls. The endovascular membrane, vascular wall thickness, intra-vascular blood flow and endovascular thrombosis formation of ulnar and radial arteries at wound site and in regions 5, 10 and 15 cm proximal to the wounds were examined by DSA and type B ultrasonography and compared with imagings of healthy volunteers as control. The injury degree of the ulnar and radial arteries was examined during operation for evaluation to corroborate with DSA and ultrasonography findings. Necrotic and/or thrombotic vessels were excised and sent for pathomorphological examination. RESULTS: By DSA images abnormal signs as thrombosis, vascular lumen stenosis and blood flow deceleration were found in 14 ulnar and 11 radial arteries, and the signs were more pronounced in ulnar arteries. By type B ultrasonography, abnormal signs as roughing of tunica intima, swelling or exfoliation, thickening of vascular wall, lumen stenosis, decreased blood flow, even necrosis of vascular wall and thrombosis were identified in 19 ulnar and 16 radial arteries in burn group (P < 0.05 approximately 0.01). The blood flow in ulnar artery 5 cm to the approximal part of the wound edge was obvious lower than that of the control (31.60 +/- 13.90 ml/min vs 47.70 +/- 9.60 ml/min, P < 0.05). CONCLUSION: Type B ultrasonography and DSA could be helpful in the evaluation of vascular injury in patients inflicted with high voltage electrical injury.

Adult↗
PubMed1984

Use of colloidal gold and ruthenium red in stereo high-voltage electron microscopic study of Con A-binding sites in mouse macrophages.

Concanavalin A (Con A)-binding sites were labeled with colloidal gold (CG), stained with ruthenium red, and observed under a high-voltage electron microscope. Mouse peritoneal macrophages were labeled by the indirect Con A/CG labeling method at 0 degree C. After washing, some of the cells were incubated in phosphate-buffered saline (PBS) at 37 degrees C. The specimens were then stained with ruthenium red, to enhance the contrast of the cell surface, and embedded in Epon. Sections (0.3 approximately 3 micron thick) were cut and examined by high-voltage electron microscopy at accelerating voltages of 200 approximately 1,000 kV. Staining with ruthenium red provided a strong contrast of the cell surface and the invaginating tubules beneath it against the cytoplasm; in thick sections, both of them were clearly seen by stereomicroscopy. CG particles which represented Con A-binding sites were also sufficiently electron dense to be recognized by high-voltage electron microscopy of thick sections. The two- and three-dimensional distribution of CG particles on the ruthenium-red-positive cell surface was clearly visualized. At 0 degree C, Con A-binding sites were randomly distributed on the cell surface. The redistribution and endocytosis of Con A-binding sites were seen at 37 degrees C. The three-dimensional organization of membrane invagination, which represented the process of endocytosis, was clearly seen by stereomicroscopy. The combination of CG labeling and ruthenium red staining is a useful method for high-voltage electron microscopic analysis of the two- and three-dimensional distribution of CG-labeled ligands on the cell surface in thick sections.

Animals↗
PubMed1979

Guinea-pig keratinocytes and melanocytes in tissue culture: scanning, transmission and high voltage electron microscope observations.

Keratinocytes and melanocytes cultured from guinea-pig epidermis were studied with scanning, transmission and high voltage electron microscopy to characterize the surface and internal morphology. Keratinocytes exhibited contact-inhibition and a range of surface structures consistent with cell-cycle dependent changes. Stereoscopic analysis of high voltage electron micrographs indicated regular oval nuclei with nucleoli at different depths, while thin sections revealed local channels in the nuclei. Secondary cultures differed from primary cultures in the disorder of the microfilaments, in the failure to form desmosomes, and in the failure of melanocytes to persist in culture. The beaded surface of melanocytes was indicative of underlying melanosomes that were seen in high voltage micrographs. Melanocytes were rounded with moderate ruffles or were dendritic with ruffles on the termini. These findings are discussed in relation to the observational techniques and in relation to modes of locomotion of and pigment transfer to epidermal cells.

Animals↗
PubMed1984

Bone marrow aplasia after high voltage electrical injury.

This report describes a patient with severe high voltage electrical injury in whom bone marrow aplasia developed on post-burn day 3. In addition to bone marrow aplasia alterations suggesting disintegration of leucocytes and reduced nitro-blue tetrazolium reductase activity pointing to functional disorders have been observed. Beyond the effect of the extensive burns to depress the bone marrow the possibility of an additional similar action of the high voltage electrical injury is raised.

Adult↗
PubMed1989

High-voltage capillary zone electrophoresis of red blood cells.

The high-voltage wide-bore capillary zone electrophoresis of red blood cells was investigated. The reproducibility of the retention time (electrophoretic mobility) is excellent and the differentiation among various species is good. The peaks in the electropherogram describe the distribution of the size and/or surface charge of the cells and are therefore broad. The relationship between the peak height and the number of cells injected is good, with linear correlation coefficients better than 0.98. Details of the preparation of cell suspensions and support electrolytes are given, which is essential for obtaining reproducible results. The inner surface of FEP capillary tubing is degraded by the application of high voltage and a pause is necessary between successive experiments if good and reproducible peak shapes are to be obtained. The length of the pause increases with the number of experiments made, and finally the tubing becomes useless. Inspection of the inner surface by X-ray photoelectron spectroscopy showed the breakdown of CHF bonds, but the actual mechanism is not known.

Animals↗
PubMed1993

Chromosome aberrations in lymphocytes of high-voltage laboratory cable splicers exposed to electromagnetic fields.

Thirteen high-voltage laboratory employees and 20 referents participated in a cross-sectional, matched-pairs study of cytogenetic damage. During cable testing the workers were exposed to static, alternating, or pulsed electric and magnetic fields. The alternating magnetic field levels of 50 Hz were 5-10 microT, occasionally much higher. Chromosome aberrations, sister chromatid exchanges, and aneuploidy were studied in peripheral blood lymphocytes. In addition, chromosome aberrations were investigated in lymphocyte cultures treated with hydroxyurea and caffeine, to inhibit deoxyribonucleic acid synthesis and repair. Among seven smoking laboratory employees the mean number of chromosome breaks/200 cells was 2.3, as compared with 0.7 for the job-matched referents. The comparable figures for inhibited cultures were 12.0 versus 6.0. No increase was detected in nonsmokers with either method. The other genetic parameters showed no differences between the exposed workers and the referents. The results support, to some extent, the hypothesis of an increased risk of genotoxic effects among high-voltage laboratory workers.

Adult↗
PubMed1999

A high voltage, constant current stimulator for electrocutaneous stimulation through small electrodes.

A high-voltage stimulator has been designed to allow transcutaneous stimulation of tactile fibers of the fingertip. The stimulator's output stage was based upon an improved Howland current pump topology, modified to allow high load impedances and small currents. The compliance voltage of approximately 800 V is achieved using commercially available high-voltage operational amplifiers. The output current accuracy is better than +/- 5% over the range of 1 to 25 mA for 30 microseconds or longer pulses. The rise time for square pulses is less than 1 microsecond. High-voltage, common-mode, latch-up power supply problems and solutions are discussed. The stimulator's input stage is optically coupled to the controlling computer and complies with applicable safety standards for use in a hospital environment. The design presented here is for monophasic stimulation only, but could be modified for biphasic stimulation.

Calibration↗
PubMed1999

Charged microbeads are not transported across the human stratum corneum in vitro by short high-voltage pulses.

There have been several reports of particle transport due to high-voltage pulsing of human skin. Here, several different short, high-voltage pulsing protocols were used in vitro to study the possible transport of highly charged, fluorescent polystyrene particles (14 nm to 2.1 microns in diameter; surface charges of -4.05 x 10(3) e to -2.77 x 10(7) e) across the skin. Two different methods were used to trap and measure particles on the other side of the skin. The first used a polycarbonate membrane to trap the particles, determining the amount of transport by enumeration under a fluorescence microscope. The second used spectrofluorimetry to measure the amount of particles transported. After pulsing, particles were found in randomly distributed clusters on the surface of the skin. No detectable transport across the stratum corneum for any size particle was observed.

Administration, Cutaneous↗
PubMedDate not supplied

[Effect of combination of high-voltage pulses and other physical factors on the intensity of reproduction of Anabaena flos aquae].

It was shown that the influence of high-voltage pulses (intensity of electric field 40-120 kV/cm) on cyanobacteria Anabaena flos aquae can be different and depends on the mode of treatment. It was found that in the range of pulse durations less than 1 microsecond with a pulse repetition rate of up to 500 Hz, and final temperature in the working chamber (60 +/- 1) degree C, a gradual full and irreversible inactivation of cyanobacteria independent of the pulse shape takes place. At the same time, a rapid (but slower than by the action of high-voltage pulses) heating without treatment with high-voltage impulses at the same final temperature leads to an inactivation of 80% of initial cyanobacteria followed by growth of bacteria up to 700% and more.

Cyanobacteria↗
PubMed2000

Induction of atrial fibrillation with rapid high voltage ventricular pacing for ventricular fibrillation conversion testing. The Ventak AV II DR Study.

OBJECTIVE: To assess whether rapid high voltage ventricular pacing can also induce atrial fibrillation, and whether the induction of atrial fibrillation during ventricular fibrillation conversion testing is related to the patient's heart disease. DESIGN: Prospective study of 50 patients who received the dual chamber implantable cardioverter-defibrillator (ICD) Ventak AV II DR (Guidant) as a first implant. This device can record atrial activity even during a ventricular fibrillation episode and can induce atrial fibrillation by rapid atrial bursts. MAIN OUTCOME MEASURES: Frequency of atrial fibrillation after induction of ventricular fibrillation; clinical characteristics of patients with and without induced atrial fibrillation; frequency of atrial fibrillation induced by rapid atrial bursts during predischarge testing. RESULTS: Atrial fibrillation was observed in 40 of the 217 ventricular fibrillation episodes (18%) that could be detected immediately after delivery of high voltage pacing. The biphasic ICD shock for termination of ventricular fibrillation also terminated the atrial fibrillation in all cases. The 40 episodes of simultaneous atrial and ventricular fibrillation occurred in 18 patients (36%). The distribution of the clinical characteristics of the patients and the inducibility of atrial fibrillation during predischarge testing were similar in those with and without induced atrial fibrillation. CONCLUSIONS: Rapid high voltage ventricular pacing frequently induces atrial fibrillation, which was terminated by the subsequent biphasic ICD shock. The induction of atrial fibrillation seems to be a non-specific phenomenon, unrelated to the clinical status of the patient.

Adult↗
PubMedDate not supplied

A comparative study on the predictive value of digital subtraction angiography and B-mode ultrasonography in evaluating arterial injury in high-voltage electrical burn of the forearm.

To compare the predictive value of digital subtraction angiography (DSA) with B-mode ultrasonography in evaluating the arterial injury in high-voltage electrical burn of the forearm, 19 forearms sustaining high-voltage electric burn were examined with DSA and B-mode ultrasonography. During surgery, the involved arteries were examined closely to compare their gross pathology with the results of DSA and B-mode ultrasonography. The thrombotic or necrotic arteries found during surgery were excised and examined pathologically. Among 19 ulnar and radial arteries examined by DSA and B-mode ultrasonography, the abnormal signs were found in 14 ulnar and 11 radial arteries in DSA, including narrowing of lumen, beading of the wall, thrombosis, and slowing of blood flow, whereas abnormal signs were shown by B-mode ultrasonography in 19 ulnar and 16 radial arteries, including roughening, edema or exfoliation of the endothelium, thickening of vessel wall, narrowing of lumen, beading of the wall, and decrease in the blood flow. The vessels with severe injuries showed thrombosis or necrosis of the vessel wall. The aforementioned changes were confirmed during surgery and pathologic examination. B-mode ultrasonography is a more efficient tool than DSA in evaluating vascular injuries of the forearm sustaining high-voltage electrical burn.

Adult↗