Microvascular free tissue transfer in reconstruction of the lower limb.

Reconstruction of the lower extremity using microvascular free tissue transfer has been adopted as a routine procedure since the 1980s. Success rates in overall free tissue transfer are now as high as 98%. In the lower limb, however, the failure rate has been reported to be as high as 15 to 20%. A review of 50 consecutive microvascular free flaps to the lower extremity was carried out in the Ulster Hospital Belfast. The indication for surgery, the flap type, the recipient vessel, re-exploration rate, complication rate, success rate and the changing pattern in management during the first six years of a single consultant's practice was assessed. Six patients (12%) were re-explored for anastomotic complications or haematoma. Thrombosis of the arterial anastomosis was noted in one case, venous thrombosis in two and haematoma under the flap in the remaining three cases. Salvage was successful in four cases, thus producing an overall success rate of 96%.     

Laparoscopic sleeve gastrectomy with endoscopic guidance in morbid obesity

BACKGROUND: Sleeve gastrectomy (SG) has been shown to be an effective first-stage procedure for morbidly obese patients. The SG is presently performed over a bougie of varying sizes, which is useful, but known to produce injuries on insertion. In a retrospective study, we evaluated the effect of the laparoscopic SG (LSG) on excess weight loss during 1 year of follow-up using a 29F endoscope instead of a bougie. METHODS: During a 1-year period, LSG was performed on 20 (18 women and 2 men) consecutive patients. Gamma regression analysis was used to determine whether the variation in gender, age, initial body mass index, Hispanic ethnicity, and interval after surgery were related to excess weight loss. RESULTS: No deaths and 1 minor complication of oozing from the staple line occurred. The excess weight loss increased steadily over time, with a median 20% at 3 months, 32% at 6 months, 42% at 9 months, and 53% at 12 months. The median initial body mass index was 44.5 kg/m2, and the median age was 50 years. Of the 20 patients, 2 were men (10%) and 18 women (90%); 5 (25%) were Hispanic and 15 (75%) were non-Hispanic. The patients had a median 11.5 co-morbidities. Nausea was common for about 7 days postoperatively. An increase in the initial body mass index and increased co-morbidities were the only 2 variables directly and statistically connected with the percentage of excess weight loss (P <.05). CONCLUSION: The results of our study have shown that LSG with endoscopic guidance appears safe and effective and could be tried using a larger set of patients as a single-stage operation.     

Nervenaktionsströme in Abhängigkeit vom Reizstrom

Zusammenfassung Bei verschiedenartigen elektrischen Reizen werden die Nervenaktionsströme von der Schwelle bis zum Maximum systematisch durchuntersucht. Als Bezugsgrößen werden ausgemessen: Latenzzeit, Anstiegszeit, Gesamtdauer und Maximalspannung. Es wird gezeigt, daß sich das Verhalten dieser Größen aus der Ladetheorie der Nervenerregung ableiten läßt und daß die theoretische Vorhersage für Latenz und Gesamtdauer ohne zusätzliche Annahmen vom Experiment bestätigt wird. Die für die Anstiegszeit gemessenen Werte entsprechen nicht ohne weiteres den theoretisch abgeleiteten; sie zeigen überhaupt kaum einen gesetzmäßigen Verlauf, was durch die Gruppenbildung der Faseraktionen erklärt wird. Die Kurve der Maximalspannung als Funktion des Reizstromes hat ungefähr die Form der Integralkurve der statistischen Variationsreihe, doch weichen die Werte im Anfangsteil ab: die gemessenen Werte sind meist kleiner als die theoretischen.Als Reizarten kommen zur Anwendung: Gleichstrom, Kondensatorstoß, Induktorschlag und einschleichender Gleichstrom. Alle Messungen werden stets mit den entsprechenden Gleichstromwerten als Standardgrößen verglichen. In Übereinstimmung mit der Theorie wird festgestellt, daß bei Kondensator- und Induktorreiz die Latenz und Gesamtdauer verkürzt sind gegenüber den entsprechenden Gleichstromwerten, daß aber bei einschleichenden Reizen Latenz und Dauer verlängert sind. Die Maximalspannung bleibt bei Gleichstrom, Kondensatorreiz und Induktorschlag praktisch unverändert, bei einschleichenden Reizen pflegt sie verkleinert zu sein.Die positive Nachschwankung wird auf zwei verschiedene Ursachen zurückgeführt: 1. eine reversible: die Regeneration der unvollkommen gequetschten Nervenfasern, 2. eine irreversible: ein wahrscheinlich physikalisch-chemischer Prozeß des Alterns oder der Abnutzung des Nerven.Zum Schluß wird darauf hingewiesen, daß die Latenzänderungen im Elektrotonus keine konstante Erscheinung eines jeden Nerven sind.D 5.     

The Prince Edward Island Conceptual Model for Nursing: a nursing perspective of primary health care.

The philosophy of primary health care (PHC) recognizes that health is a product of individual, social, economic, and political factors and that people have a right and a duty, individually and collectively, to participate in the course of their own health. The majority of nursing models cast the client in a dependent role and do not conceptualize health in a social, economic, and political context. The Prince Edward Island Conceptual Model for Nursing is congruent with the international move towards PHC. It guides the nurse in practising in the social and political environment in which nursing and health care take place. This model features a nurse/client partnership, the goal being to encourage clients to act on their own behalf. The conceptualization of the environment as the collective influence of the determinants of health gives both nurse and client a prominent position in the sociopolitical arena of health and health care.     

Verbascoside isolated from Lantana camara, an inhibitor of protein kinase C.

Verbascoside [1] isolated from Lantana camara is an inhibitor of protein kinase C (PKC) from the rat brain. Half-maximal inhibition of the kinase occurs at 25 microM. Verbascoside interacted with the catalytic domain of PKC and was a competitive inhibitor with respect to ATP (Ki = 22 microM) and a non-competitive inhibitor with respect to the phosphate acceptor (histone IIIS). This effect was further evidenced by the fact that verbascoside inhibited native PKC and its catalytic fragment identically and did not affect [3H]-phorbol-12,13-dibutyrate binding to PKC. The antitumor activity of verbascoside measured in vitro might be due at least in part to inhibition of PKC.     

Efferent projections of the infralimbic cortex of the rat.

On the basis of stimulation studies, it has been proposed that the infralimbic cortex (ILC), Brodmann area 25, may serve as an autonomic motor cortex. To explore this hypothesis, we have combined anterograde tracing with Phaseolus vulgaris leucoagglutinin (PHA-L) and retrograde tracing with wheat germ aggutinin conjugated to horseradish peroxidase (WGA-HRP) to determine the efferent projections from the ILC. Axons exit the ILC in one of three efferent pathways. The dorsal pathway ascends through layers III and V to innervate the prelimbic and anterior cingulate cortices. The lateral pathway courses through the nucleus accumbens to innervate the insular cortex, the perirhinal cortex, and parts of the piriform cortex. In addition, some fibers from the lateral pathway enter the corticospinal tract. The ventral pathway is by far the largest and innervates the thalamus (including the paraventricular nucleus of the thalamus, the border zone between the paraventricular and medial dorsal nuclei, and the paratenial, reuniens, ventromedial, parafasicular, and subparafasicular nuclei), the hypothalamus (including the lateral hypothalamic and medial preoptic areas, and the suprachiasmatic, dorsomedial, and supramammillary nuclei), the amygdala (including the central, medial, and basomedial nuclei, and the periamygdaloid cortex) and the bed nucleus of the stria terminalis. The ventral efferent pathway also provides descending projections to autonomic cell groups of the brainstem and spinal cord including the periaqueductal gray matter, the parabrachial nucleus, the nucleus of the solitary tract, the dorsal motor vagal nucleus, the nucleus ambiguus, and the ventrolateral medulla, as well as lamina I and the intermediolateral column of the spinal cord. The ILC has extensive projections to central autonomic nuclei that may subserve a role in modulating visceral responses to emotional stimuli, such as stress.     

Microsurgical Posterior Fossa Vestibular Neurectomy: An Evolution in Technique

Between 1925 and 1945, Walter Dandy and Kenneth McKenzie performed more than 700 posterior fossa eighth nerve sections and vestibular neurectomies, treating the intractable vertigo accompanying Meniere's disease. During the past 10 years, using microsurgical techniques and reaching the posterior fossa through the temporal bone, vestibular neurectomy has enjoyed a resurgence of popularity. When hearing is to be preserved, vestibular neurectomy is the surgical treatment of choice, if the patient fails to undergo a remission of the vertigo of Meniere's disease. This report reviews 115 consecutive vestibular neurectomies performed for the treatment of Meniere's disease from 1978 to 1988.

In 1978, the retrolabyrinthine vestibular neurectomy (RVN) was introduced, a procedure in which the posterior fossa is entered anterior to the sigmoid sinus and behind the labyrinth. During the last three years, the approach to the posterior fossa has been a small dural opening behind the sigmoid sinus, the combined retrolabyrinthine-retrosigmoid (R-R) approach. There have been no cases of facial paralysis and no serious complications. A high incidence of headache (75%) resulted when the posterior wall of the internal auditory canal was drilled away for better exposure. Transient cerebrospinal fluid (CSF) leaks occurred in 7% of the patients having the RVN, the incidence was 3% when the combined R-R approach was used. In the RVN series, wound infection occurred in 20% of cases until perioperative antibiotics reduced the rate to 3%. The results in curing or improving vertigo have been excellent (94%), and hearing has been preserved to within 20 dB of the preoperative levels in 76%. Until a cure for Meniere's disease is found, microsurgical posterior fossa vestibular neurectomy remains the best treatment.

     

The Influence of Photoperiod on the Hypothalamic Content of Beta-Endorphin and the Luteinizing Hormone Responses to Naloxone and to Steroid Withdrawal in the Male Syrian Hamster

The aim of this study was to investigate the influence of inhibitory photoperiods upon opioidergic function, as determined by changes in the hypothalamic content of β-endorphin and the luteinizing hormone response to opioidergic receptor blockade, in the male Syrian hamster over the course of gonadal involution and spontaneous gonadal recrudescence. Animals exposed to an 8 h light: 16 h dark cycle (8L: 16D) for 14 weeks underwent gonadal regression. Regression was also observed in animals held for 7 weeks on one of a range of short daylengths of between 11.5 h and 13.5 h, the degree of atrophy being greatest in those animals on the shortest daylength. The tissue concentration of β-endorphin within the mediobasal hypothalamus was significantly higher in animals exposed to 8L: 16D for 14 weeks than in gonadally active controls held on long days (16L: 8D). Exposure to photoperiods of less than 13.5 h for 7 weeks also caused a significant increase in the β-endorphin content of the mediobasal hypothalamus and there was a positive correlation between the concentration of β-endorphin, the degree of gonadal atrophy and the shortness of the photoperiod. Endorphin levels within the preoptic area were not affected by photoperiodic treatments. Exposure of intact animals to 8L: 16D for 12 weeks caused gonadal atrophy and an associated loss of the luteinizing hormone responses to both naloxone and castration. Castrated animals receiving testosterone replacement (cast + T) also exhibited photoinhibition, in the form of reduced serum levels of luteinizing hormone, and this was similarly accompanied by a loss of sensitivity to naloxone and to withdrawal of steroid. Prolonged exposure to 8L:16D led to spontaneous reactivation of the gonadotrophic axis as a consequence of the development of scotorefractoriness. In both gondally intact animals and in cast + T groups, this was associated with a restoration, in parallel, of the luteinizing hormone responses to naloxone and to castration/ steroid withdrawal. The time-course of the restoration of the response to steroid withdrawal in castrates was not significantly different to that observed in intact animals. The luteinizing hormone response to naloxone took significantly longer to redevelop in cast + T groups than it did in gonadally intact animals. The data demonstrate that central opioid systems are sensitive to photoperiod and are consistent with the hypothesis that opioids are involved in the neuroendocrine regulation of reproductive responses to daylength.     

Continuous Electrical Stimulation as a Helpful Adjunct During Intraoperative Facial Nerve Monitoring

Routine intraoperative monitoring of facial function has been used since 1985. An adaptor has been developed for continuous stimulation (SACS) to be used with the new WR-S8, Monitor/Stimulation The SACS allows the microsurgical instruments and air drills to be electrified and to function as probe tips during surgical dissection. The new WR-S8 Monitor/Stimulator has an ultrasensitive strain gauge that detects facial movement before it is palpable. The remote probe allows an assistant to adjust the current easily. The routine use of facial nerve monitoring with SACS has decreased surgical time, has helped prevent iatrogenic injuries, and has improved our ability to save the facial nerve during otologic and neuro-otologic surgery.