Glucagon for refractory asthma exacerbation

Glucagon, a hormone secreted by pancreatic alpha cells, causes bronchial smooth muscle relaxation by activating the synthesis of cyclic adenosine monophosphate. It was studied in the 1980s and 1990s as a treatment option for the management of asthma but has since not been evaluated. Data to support its use are limited, but it may serve as a last-line agent for refractory asthma exacerbation. Here we describe 4 cases in which intravenous glucagon was used to manage severe, refractory asthma exacerbation in the emergency department.     

Angiotensin II is a necessary component for the development of hypertension in the two kidney, one clip rat

The current study was undertaken to define the role of the renin-angiotensin system in the development of hypertension in the two kidney, one clip Goldblatt rat. Captopril was administered orally (100 mg/kg/day) to two groups of rats (n = 8 each) 24 hours before and each day after unilateral renal artery clipping (0.2 mm internal diameter): the drug was given for either 16 weeks (group I) or 24 weeks (group II). Sham-operated (n = 5) and Goldblatt (n = 8) rats not receiving captopril were prepared for comparisons of plasma renin activity and systolic blood pressure. Indomethacin (20 mg/kg/day subcutaneously) was administered for 48 hours concomitantly with captopril to the rats in group I. In group II, systolic blood pressure was monitored for 7 weeks after cessation of captopril. Continual captopril administration to Goldblatt rats completely prevented the rise in systolic blood pressure, a rise that was observed in Goldblatt rats not receiving captopril. Whereas systolic blood pressure of captopril-treated rats approximated 100 mm Hg throughout the study, that of Goldblatt rats not receiving the drug increased to nearly 180 mm Hg within 6 weeks after clipping. Systolic blood pressure of sham-operated rats remained normal. Indomethacin did not change systolic blood pressure in the drug-treated rats in group I. On cessation of captopril therapy in group II, systolic blood pressure increased gradually in a manner that paralleled the development of the disease in the Goldblatt rats that did not receive captopril. Plasma renin activity was determined in Goldblatt and sham-operated rats at either 16 weeks (group I) or 24 weeks (group II) after clipping; the rats from either group with mild hypertension (systolic blood pressure less than 180 mm Hg) had normal plasma renin activity whereas those with severe hypertension (systolic blood pressure greater than 180 mm Hg) had greatly elevated plasma renin activity. In summary, captopril can completely prevent the increase in systolic blood pressure for up to 24 weeks in Goldblatt rats, and this hypotensive effect is not mediated by the prostaglandins. It is concluded that the renin-angiotensin system is a necessary component of the hypertensive process in this experimental model.     

Two-dimensional echocardiographic preoperative prediction of prosthetic aortic valve size

Aortic root diameter was measured by two-dimensional (2DE) and M-mode echocardiography in 20 adult patients (aged 29 to 69 years) undergoing aortic valve replacement in order to predict prosthetic aortic valve size. Eight patients had predominantly aortic stenosis, six had chronic aortic regurgitation, and six had acute severe aortic regurgitation secondary to infective endocarditis. 2DE measurements of aortic anulus diameter, as determined from the parasternal long-axis view, demonstrated a high correlation with actual prosthetic valve size implanted at surgery (r = 0.89, p less than 0.001, SEE 0.68 mm). 2DE exactly predicted actual prosthetic valve size in 12 of 20 patients (60%), was within 1 mm of prosthetic valve size in 6 of 20 patients (30%), and was within 2 mm of prosthetic valve size in two patients. In contrast, M-mode echocardiography failed to significantly predict aortic valve size (r = 0.14) because of its lack of two-dimensional anatomic orientation. Thus 2DE can safely and accurately predict preoperatively prosthetic aortic valve size and thereby be of great value in helping to avoid the problem of prosthesis-patient mismatch.     

Recovery of blood-borne bacteria from human urine

Recovery from the urine of organisms causing bacteraemia may depend on the bacterial species involved. The survival of the more common species of bacteria which cause bacteraemia was examined in human urine, serum and normal saline. All species survived well or grew in serum. Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus sanguis and group A streptococci were killed in all urine samples. The number of colony-forming units of Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus and group B streptococci either remained the same or increased in the urine, while the numbers of Escherichia coli and Klebsiella pneumoniae increased rapidly. These data suggest that the observed differences in recovery from urine of these bacterial species that cause bacteraemia are related to the viability of the species in human urine.     

A comparative study of the effects of mercury compounds on cell viability and nucleic acid synthesis in HeLa cells

The effects of various mercury compounds on HeLa cell viability and DNA and RNA syntheses in intact cells and in isolated nuclei have been studied. The compounds examined were: methylmercuric chloride, ethylmercuric chloride, dimethylmercury, phenylmercuric acetate, p-hydroxymercuribenzoate, p-hydroxymercuribenzenesulfonate, HgCl2, HgSO4 , Hg(ClO4)2 and Hg2(ClO4)2. All of the compounds except dimethylmercury inhibited colony formation as well as DNA synthesis in intact cells and in isolated nuclei. RNA synthesis in intact cells was inhibited by all the compounds except dimethylmercury, p-hydroxymercuribenzoate and Hg(ClO4)2. In isolated nuclei, alpha-amanitin-resistant RNA synthesis was inhibited by all the compounds except dimethylmercury, alpha-Amanitin-sensitive RNA synthesis was stimulated by some compounds, inhibited by some, and unaffected by others. The effects of two non-mercurial sulfhydryl reagents, N-ethylmaleimide and iodoacetic acid, were also examined. These compounds showed a pattern of effects on nucleic acid synthesis which differed considerably from that of the mercury compounds. Neither compound significantly inhibited alpha-amanitin-resistant RNA synthesis in isolated nuclei, although both inhibited RNA synthesis in intact cells. Iodoacetic acid had no inhibitory effect on DNA synthesis in isolated nuclei but strongly inhibited DNA synthesis in intact cells.     

Crestal ostectomy and lateral wall compression for management of the enlarged pneumatized tuberosity

The crestal ostectomy with lateral antral wall compression is a simple, predictable procedure to correct soft tissue and osseous hypertrophy in the pneumatized maxillary tuberosity. It offers certain advantages over other techniques: 1) simultaneous reduction of vertical and lateral aspects of the hyperplastic tuberosity; 2) simultaneous revision of hypertrophic or mobile mucosal tissue overlying the tuberosity; 3) avoidance of a hrizontal scar band in the buccal vestibule, which may subsequently interfere with the denture flange; 4) negligible effect on the depth of the buccal vestibule; 5) fixation wires are not required; 6) rapid healing of the osteotomy site, since there is intimate bony contact; 7) expedient initiation of denture fabrication is possible because the palatal aspect of the tuberosity is not mobilized; and 8) no surgical stent is necessary.