The use of external, noninvasive pacing for the termination of supraventricular tachycardia in the emergency department setting

STUDY OBJECTIVE: To determine the potential feasibility of external cardiac pacing for the termination of sustained supraventricular tachycardia in the emergency department setting. TYPE OF PARTICIPANTS: Three men and two women (mean age, 34 years) who presented to the ED with a narrow-complex, hemodynamically stable tachycardia that was later proven to be supraventricular in origin. INTERVENTION: Each patient underwent external overdrive pacing using a modified external pacemaker at a pulse amplitude of 120 mA and a rate between 240 and 280 pulses per minute. RESULTS: In four patients, external cardiac pacing was able to successfully terminate the tachycardia without complication. In one patient, the pacemaker was not able to terminate the tachycardia. CONCLUSION: We conclude that external, noninvasive pacing is a feasible means of terminating supraventricular tachycardia in the ED setting.     

Use of sea water in the flotation of carbonate rich sedimentary phosphate rock

There is an appreciable amount of carbonaceous sedimentary phosphate deposits in the northern Africa and the Middle East which are expected to gain importance in the near future because of the depletion of the deposits in Florida. In many of the regions where phosphate deposits are found there is a shortage of fresh water, and sea is not very far. The use of sea water instead of fresh water in flotation of carbonaceous phosphate rock is successfully demonstrated. Thus an appreciable reduction in the operating cost and an ample amount of saving in the fresh water resources of the region is expected.     

Characterization of trace amounts of odorants (sulfur compounds, oxygenates, hydrocarbons, phenols and lower fatty acids) in air in an ICU room

Characterization of trace amounts of odorants in air in an ICU room (ca.257m2) was carried out by gas chromatography and atmospheric pressure ionization-mass spectrometry (API-MS). The concentrations and odor recognition threshold values of the detected odorants, acetaldehyde, ethanol, n-butyric acid, iso-valeric acid and n-valeric acid are as follows: 44.7 ppb and 15 ppb; 19710 ppb and 6100 ppb; 0.50 ppb and 0.4 ppb; 0.45 ppb and 0.4 ppb; 0.67 ppb and 0.5 ppb, respectively. The detected concentrations of these odorants were significantly higher than the odor recognition threshold values. The compounds may, therefore, be responsible for perception of such odors as mixed odors, body odor, and faint or recognizable alcoholic odor, disinfectant odor, and sour, pungent, and goat odors.     

Fever, negative blood culture findings and absence of response to antibiotic therapy in a patient after a second aortic valve prosthesis

HISTORY AND CLINICAL FINDINGS: A 53-year-old patient had a prosthetic valve (St. Jude Medical 25) 9 years ago because of a Staphylococcus aureus endocarditis with severe aortic regurgitation. An initially mild, progressively more severe, aortic regurgitation then developed as a result of an empty paravalvular abscess cavity, requiring another valve replacement. Fever started on the 3rd postoperative day and persisted despite combined treatment with beta-lactam antibiotics and aminoglycoside. INVESTIGATIONS: At first no infectious focus could be identified radiologically or by echocardiography. But transoesophageal echocardiography revealed vegetations in the old abscess cavity. Several blood cultures were negative, while serological tests gave markedly raised antibody titers against Coxiella burnetii. DIAGNOSIS, TREATMENT AND COURSE: Assuming Coxiella burnetii endocarditis the patient was given doxycycline, 2 x 100 mg daily and cotrimoxazole, 1 x 960 mg daily. The fever subsided and the vegetations had disappeared after four weeks. Because of the high risk of recurrence the antibiotic treatment was to be continued for two years. CONCLUSION: Coxiella burnetii should be considered as a possible cause of fever of unknown origin, especially in patients with existing or operated cardiac valvar defects, when endocarditic vegetations have been demonstrated and several blood cultures have been negative.     

Low-noise properties of dry gate recess etched InP HEMTs

Lattice-matched InAlAs-InGaAs HEMTs with dry etched and wet etched gate recesses have been fabricated and both high-frequency and noise measurements have been carried out. The highly selective dry etching process ensures uniform device parameters. The small signal and noise performance shows only minor differences between the two transistor types. There is no evidence of detrimental effects caused by dry etching that reduce the electrical and noise performance of the device at high frequencies. These results show that dry etched InP HEMT's have suitable characteristics for the fabrication of MM-wave integrated circuits     

Morphologic changes in the lens epithelium in patients with age-induced cataract, radiation and steroid cataract and cataract following eye contusion

The lens epithelium of the human eye plays a crucial role in the pathogenesis of primary and secondary cataract. Sixty hematoxylin-eosinstained lens epithelia were examined using a light microscope. Cell parameters were compared to one another in the various age groups of patients, between patients with secondary cataract (radiation cataract, steroid cataract and traumatic cataract) and patients with senile cataract, and between male and female patients. The t-test was used for statistical comparison. The median cell density was 3116.5 cells/mm2. The median nucleus-plasma ratio was 1:2.74. Patients with secondary cataract had a larger medium cell and nucleus area as well as a higher nucleus-plasma ratio and a lower cell density than patients with senile cataract. A part from degenerative and proliferative cell changes we found various cell types. The age of patients and the cause of cataract correlate with morphometric changes of lens epithelium cells. However, there was no correlation between specific cytologic changes and causes of cataract.     

Analysis of MTF degradation in the imaging of cells in a flow system

The time-delay and integration method can be used with a charge-coupled device array to acquire images of cell in a flow cytometer. The loss of high spatial frequency components in images acquired with this technique is studied by deriving the modulation transfer function (MTF) for each of the main causes of image degradation: finite sampling aperture, nonsynchronism between image movement and charge transfer rate, discrete charge motion, transfer inefficiency, and axis misalignment. The system MTF and resolution in the horizontal and vertical directions are then examined.©1994 John Wiley & Sons Inc     

Determination of complements in serum and middle ear effusion of the patients with secretory otitis media

Complements in serum and middle ear effusion were determined in 20 patients with secretory otitis media, and compared with those in the normal controls. The C5 and C1-INH in serum of the patients were significantly higher. On the contrary, C9 and B factor (Bf) were significantly lower, and the circulatory immunocomplex was also higher. In patients with secretory otitis media, the middle ear effusion levels of C3, C4 and C5 were significantly lower, and Bf and immunocomplex were significantly higher than those in serum. The results suggest that the ability of complements in clearing immunocomplex is low. Therefore, the immunocomplex may deposit in the mucosa of the middle ear. Thus the permeability of capillary will be increased, and the middle ear effusion occurs.