Implant-supported prostheses for treatment of adults with cleft palate

Six adult patients with cleft palate, ranging in age from 47 to 78 years, were treated with self-tapping titanium implants. Twenty-three implants, 7 to 15 mm in length, were placed. Of these, one (4%) was 7 mm, eight (35%) were 10 mm, nine (39%) were 13 mm, and five (22%) were 15 mm. Time between stage I and stage II implant surgeries was 5 to 14 months, averaging 8.3 months. Time from stage II surgery to the present is 1.5 to 5 years, averaging 3 years. Of the 23 implants placed, 21 (91%) achieved osseointegration. One (4%) implant was not used prosthetically. Two (9%) 10 mm implants failed to integrate in one patient. All patients were treated with a maxillary complete denture or overdenture. Five (83%) required the addition of a pharyngeal section for speech enhancement.     

Correlation between leukotriene D4-induced contraction and cytosolic calcium elevation: a quantitative and simultaneous evaluation in smooth muscle

The role of Ca++ as an intracellular messenger in leukotriene (LT)D4-induced muscle contraction was investigated by measuring force development and elevation in cytosolic Ca++ concentration simultaneously in strips of guinea pig ileal longitudinal muscle loaded with the fluorescent calcium indicator Fura 2. Upon addition of LTD4, a simultaneous increase in tension and cytosolic calcium concentration, [Ca++]i, was observed. Cumulative applications of LTD4 induced concentration-dependent increases in both muscle tension and [Ca++]i, being the half-maximal effect reached at approximately 6 to 9 nM. A statistically significant positive correlation (r = 0.993, P < .001) exists between the two parameters examined. Removal of calcium in the bathing solution, accompanied by addition of 7.5 mM EGTA, completely prevented any increase in either calcium levels or force development, thus indicating a role for Ca++ influx, rather than a release from intracellular stores. All of the LTD4 antagonists tested were able to counteract the effect of the leukotriene on both [Ca++]i and tension increase. However, although LY171883 shifted both of the LTD4 curves to the right in a parallel fashion, FPL 55712 and ICI 198,615 behaved as non-competitive antagonists in reversing the effect of LTD4 on [Ca++]i and tension. Thus, these results strongly suggest that changes in muscle tension induced by LTD4 are attributable to changes in cytosolic free Ca++ concentrations in guinea pig ileum.     

An improved system for the control of dissolved oxygen in freshwater aquaria

A system for the removal and control of dissolved oxygen (DO) from freshwater was designed and constructed with aquarium-type fish studies in mind. Degassed water was obtained using a partial vacuum of -14 psi, and DO regulated at an aquarium scale using electronically controlled aeration with timed partial water renewal. The degassing system was capable of producing water with approximately 1.7 mg L(-1) DO within 10 min of operation, and 0.55 mg L(-1) after 2h. The control system was capable of maintaining DO levels of ca 0.8 mg L(-1) over 48 h in the absence of aeration and further capable of precisely controlling DO levels as low as 1.16+/-0.002 mg L(-1) (mean+/-SEM) with aeration over a 48 h period.     

Effect of profound hearing loss on a central auditory nucleus

The present study was designed to investigate the type and extent of degeneration occurring in the human central auditory system subsequent to profound hearing loss. The authors have examined the size of one population of neurons in the ventral cochlear nucleus in seven subjects with profound hearing loss (audiometric responses poorer than 90-100 dB HL). Six normal subjects, ages 35-78, were used as controls. Cell size in the hearing-impaired subjects ranged from normal to reduced by more than 50 percent. Two factors appear to contribute to the variability in cell size reduction. The correlation coefficient (Spearman rs) of cell size with duration of profound deafness was -0.48, indicating a moderate tendency for neurons to become smaller with longer periods of deafness. The correlation coefficient of cell size with number of surviving cochlear ganglion cells was 0.73, indicating a stronger tendency for neurons to be larger with greater eighth nerve innervation of the cochlear nucleus. Two cases of Scheibe degeneration showed the most severe degenerative change in the central auditory system.     

Active surveillance of health and safety in microbiology laboratories

In microbiology laboratories highly infectious material is handled alongside complex and potentially dangerous equipment, and staff are therefore at risk of infections and accidents. Acts of parliament and regulations exist to protect staff in the workplace, including those exposed to biological agents. The current monitoring of health and safety in laboratories seeks to ensure that employers and employees comply with existing regulations, but this form of passive surveillance is of limited value because it does not highlight shortcomings in techniques, equipment, premises, or personnel. We propose a scheme for the surveillance of health and safety in microbiology laboratories that will actively seek information about laboratory incidents and practices, in order to enable appropriate preventive measures to be instituted.     

Association between oxygen delivery and consumption in patients undergoing cardiac surgery. Is there supply dependence?

Numerous investigators have suggested that cell glycoconjugates are modified by the development of cancer and the progression of this to a malignant form. Accordingly, in the present work, beta-D-galactosidase, alpha-L-fucosidase, beta-N-acetyl-D-glucosaminidase and beta-N-acetyl-D-galactosaminidase activities were studied in human thyroid and gastric tumours. Samples were obtained from human gastric mucosa and thyroid gland tumours together with a part of the surrounding normal tissue (control). Enzyme activity was determined spectrophotometrically based on the release of p-nitrophenol from suitable p-nitrophenyl-derivative substrates. Results showed that beta-D-galactosidase, alpha-L-fucosidase, beta-N-acetyl-D-glucosaminidase and beta-N-acetyl-D-galactosaminidase activities were detected in tumour and control samples from thyroid and gastric tissues. The gastric mucosa also showed alpha-L-mannosidase activity. The specific activities of these glycosidases were higher (two- or three-fold) in tumour tissues as compared with their controls. beta-D-galactosidase, beta-N-acetyl-D-glucosaminidase and beta-N-acetyl-D-galactosaminidase activities from thyroid and gastric tumours showed a significant increase in V(max) as compared with their respective controls (P < 0.05 or P < 0.001). Thyroid alpha-L-fucosidase activity showed a statistically and significantly increased affinity (lower K(m)) in tumour samples as compared to normal tissue. In conclusion both gastric and thyroid tumours showed enhanced glycosidase activity as compared with enzyme activity observed in normal tissue. These results are in agreement with the notion of a markedly raised degradation within lysosomes of tumour cells.     

Electron transfer reactions in RB90745, a bioreductive drug having both aromatic N-oxide and nitroarene moieties

This study defines the current modes of treatment of patients with uterine fibromas with a review of the literature. Progesterone treatments appear to be principally used in cases of minor functional symptomatology and we discuss recent studies of mifepristone. GnRH agonists are particularly effective in preoperative treatment for conservative surgery. The indications and results of hysteroscopic resection and laparoscopic myomectomy are compared to those of classic myomectomy and hysterectomy. The indications for myolysis are discussed.