Management of adipsia by a behavioural modification technique

Adipsia combined with diabetes insipidus after hypothalamic damage may produce major difficulties in clinical management. If there is an associated memory impairment it may be impossible to teach self-regulation of fluid balance, necessitating long-term hospital supervision. The successful use of a behaviour modification technique to achieve independent drinking and allow discharge from hospital into the community is described in a patient with adipsia, diabetes insipidus and memory impairment resulting from the removal of a craniopharyngioma.

Single-ion Setschenow coefficients for several hydrophobic non-electrolytes in aqueous electrolyte solutions

Setschenow coefficients have been derived from solubility measurements on cyclohexane, benzene, naphthalene, 1-naphthol, 1,5-dihydroxynaphthalene, and anthracene in alkali halide, tetraalkylammonium bromide, and tetraphenylarsonium chloride aqueous solutions at 298.2 K. Single ion Setschenow coefficients have thence been obtained by an assumption involving extrapolation of the tetraalkylammonium bromide results to zero cation volume. Setschenow coefficients for the tetraalkylammonium cations correlate well with a hydrophobicity parameter based on their transfer chemical potentials from water into 1,2-dichloroethane. Keywords: solubilities, aqueous salt solutions, Setschenow coefficients.

Characterization of albumin-alginic acid complex coacervation

Complex coacervation of albumin and alginic acid has been investigated to characterize this process, and to prepare a microencapsulation system suitable for the encapsulation of live cells, protein and polypeptide drugs. The optimum conditions of pH, ionic strength and total polyion concentration were in accordance with predictions based on the method of Burgess & Carless (1984). Albumin/alginic acid complex coacervation appears to fit the Vies-Aranyi model for complex coacervation. Coacervation was limited compared with other polypeptide/polysaccharide systems such as gelatin and acacia, with albumin/alginic acid complex precipitates rather than complex coacervates forming under certain conditions. In particular coacervation was limited to concentrations below 0.5% w/v. At concentrations between 0.35 and 0.5% w/v both complex coacervation and precipitation occurred, and at concentrations above 0.5% w/v only precipitation was detected. The albumin/alginic acid complex coacervate is very viscous and this together with the limited conditions governing the occurrence of coacervation makes this system unsuitable for the preparation of microcapsules.

Internalization and activation of the rat liver insulin receptor kinase in vivo

The preparation of clearly delineated plasmalemma (PM) and endosomal subcellular fractions from rat liver has allowed us to compare insulin receptor (IR) kinase activity at the cell surface and in hepatic endosomes (ENs) as a function of dose and time after injected insulin. Tyrosine kinase activity in PM and ENs was measured, after solubilization and partial purification by wheat germ agglutinin chromatography (lectin-purified), using poly(Glu:Tyr) as substrate. Following the injection of a subsaturating dose of insulin (1.5 micrograms/100 g body weight), lectin-purified receptor showed peak activation at 30 s in PM and at 2 min in ENs. As observed previously (Khan, M. N., Savoie, S., Bergeron, J. J. M., and Posner, B. I. (1986) J. Biol. Chem. 261, 8462-8472) autophosphorylation activity was also augmented following insulin injection. In a pattern virtually identical to that of exogenous kinase activity, autophosphorylation attained peak activity at 30 s in PM and at 2 min in ENs. The time course of IR autophosphorylation in intact membranes was very similar to that observed for lectin purified receptors and was seen with an injected insulin dose as low as 150 ng/100 g body weight. Phosphatase treatment of the solubilized endosomal receptor abolished its enhanced activity. Hence, insulin treatment led to in vivo receptor phosphorylation which was reflected in the enhancement of both tyrosine kinase and autophosphorylation activities. Significant differences in the phosphorylation activities of PM and ENs were observed. Phosphoamino acid analyses revealed that the activated IR of intact PM was autophosphorylated in vitro, at both serine (55%) and tyrosine (45%) residues; whereas the activated IR of intact ENs was phosphorylated in vitro exclusively on tyrosine autophosphorylation specific activity for the activated IR of ENs was 3- to 4-fold that of the IR of PM. This was observed for the lectin purified IRs as well as for IRs of intact cell fractions. The reduced level of IR autophosphorylation in PM was not due to occlusion of tyrosine acceptor sites by prior in vivo phosphorylation. The rapidity with which activated IR accumulates in ENs as well as the sensitivity of endosomal IR kinase to activation by injected insulin are consistent with the endosomal apparatus serving a physiologically significant site for the regulation of transmembrane signaling.

Reliability of visual analog and verbal descriptor scales for "objective" measurement of temporomandibular disorder pain

Eight dentists viewed standardized videotapes showing palpations of the temporomandibular joint and muscles of mastication and recorded their judgments concerning the amount of pain the patient was experiencing. Judgments were recorded using a four-point verbal descriptor scale (VDS) ("none", "mild", "moderate", "severe" pain) or a 100-mm visual analog scale (VAS) anchored with the terms "no pain" and "worst pain possible". Test/re-test reliability over a one-week period and interjudge reliabilities were calculated for each scale; reliabilities of the two scales were directly compared based on the statistical equivalence of weighted kappa and the Intraclass Correlation Coefficient. Neither scale showed satisfactory reliability. Median test/re-test reliabilities were k = 0.590 for the VDS and r = 0.822 for the VAS. Interjudge reliabilities averaged k = 0.394 for the VDS and r = 0.735 for the VAS. Direct comparison of reliabilities for the two scales showed no clear advantage for either scale. The marginal reliabilities of these scales, when used by dentists to quantify the patient's pain, suggest that neither scale should be regarded as an "objective" pain measure.

Anatomical study of the cavernous sinus emphasizing operative approaches and related vascular and neural reconstruction

The efficacy of three operative approaches to the cavernous sinus (CS) and the possibilities of vascular and cranial nerve reconstruction in and around the CS were studied in 50 cadaver specimens (25 heads). The lateral operative approach was through the lateral wall, between Cranial Nerves V1 and IV, or between Cranial Nerves V1 and V2. The superior approach was through the superior wall of the CS after removing the anterior clinoid process and unroofing the optic canal. The inferior approach followed the petrous internal carotid artery (ICA) into the CS after an extradural subtemporal exposure or after a combined subtemporal and infratemporal fossa exposure. The different exposures of the spaces of the CS and of the intracavernous structures provided by the superior and the lateral approaches were complementary. The exposure provided by the inferior approach was minimal; however, the junction of the petrous and cavernous ICA was best exposed by this route. The combined subtemporal and infratemporal fossa approach exposed the petrous ICA (for proximal control or for reconstruction) with the greatest ease and with the least temporal lobe retraction. The combination of the superior and lateral approaches and the complete mobilization of the intracavernous ICA facilitated its repair after experimental lacerations. Lacerations of either the inferior and the inferomedial aspects of any portion of the cavernous ICA or of the anterior surface of the posterior vertical segment of the artery were the most difficult to repair. End-to-end anastomosis was more difficult with the posterior third of the artery than with the anterior two-thirds. A vein graft with an average length of 3.5 cm could be sutured from the petrous to the supraclinoid ICA to bypass the cavernous ICA, with an average occlusion time of 45 minutes. End-to-end technique was judged better for the proximal anastomosis, but end (graft)-to-side anastomosis was easier to perform at the distal end because of the location of the ophthalmic artery. Resuture of Cranial Nerves III and VI could not be performed in fresh cadavers if the gap exceeded 0.3 cm. In 3 specimens, the exposure of Cranial Nerve VI in the posterior fossa through the petrous apex and in the orbital apex was followed by graft placement (bypassing the CS). The complex anatomy of the cranial nerves at the apex of the CS was also defined in 10 specimens. Surgeons who perform operations in and around the CS for neoplastic and vascular lesions will find these studies useful.

Penetrating chest wounds: a 10-year review

From January 1975 to December 1984, 93 patients with penetrating chest wounds were admitted to three hospitals in Regina. Sixty-three percent of the wounds were caused by knives and 34% by firearms. Sixty-three patients were treated conservatively, 18 patients had thoracotomy and 12 others underwent laparotomy. Of the 18 patients, 16 had wounds between the nipples; 8 of the 16 had injuries to the heart or great vessels. Whereas the majority of penetrating wounds to the chest may be treated by observation or thoracostomy alone, a surgical approach is recommended when penetrating injuries are thought to have traversed the mediastinum, because of the high incidence of associated cardiac injuries. In doubtful cases the decision should favour early thoracotomy.