Current State of Skin Cancer Prevention: A Systematic Review. / Situación actual de la prevención del cáncer de piel: una revisión sistemática.

Skin cancer deaths continue to rise despite the implementation of numerous preventive campaigns and programs. The aim of this systematic review was to evaluate reviews of primary and secondary skin cancer prevention strategies as reported over the past 10 years. We analyzed 63 systematic reviews and meta-analyses: 30 (46.6%) addressing primary interventions and 35 (55.6%) addressing secondary interventions. Two of the reviews covered both. The most widely reported primary prevention approaches were education programs (63.3%), followed by risk modeling to identify individuals at high risk for melanoma (17.6%), and the promotion of sunscreen use (11.8%). The most widely reported secondary prevention measures concerned imaging systems for early skin cancer detection (40%), smartphones and new technologies (22.9%), and visual diagnosis in population-based screening (17.4%). The most effective measures were primary prevention education programs to improve sun protection habits.

Liver transplant with controlled donors after circulatory death with normothermic regional perfusion and brain dead donors: A multicenter cohort study of transfusion, one-year graft survival and mortality.

BACKGROUND: Controlled donation after circulatory death (cDCD) has expanded the donor pool for liver transplantation (LT). However, transfusion requirements and perioperative outcomes should be elucidated. The aim of this multicenter study was to assess red blood cell (RBC) transfusions, one-year graft and patient survival after LT after cDCD with normothermic regional perfusion (NRP) compared with donors after brain death (DBD). METHODS: 591 LT carried out in ten centers during 2019 were reviewed. Thromboelastometry was used to manage coagulation and blood product transfusion in all centers. Normothermic regional perfusion was the standard technique for organ recovery. RESULTS: 447 patients received DBD and 144 cDCD with NRP. Baseline MCF Extem was lower in the cDCD group There were no differences in the percentage of patients (63% vs. 61% p = 0.69), nor in the number of RBC units transfused (4.7 (0.2) vs 5.5 (0.4) in DBD vs cDCD, p = 0.11. Twenty-six patients (6%) died during admission for LT in the DBD group compared with 3 patients (2%) in the cDCD group (p = 0.15). To overcome the bias due to a worse coagulation profile in cDCD recipients, matched samples were compared. No differences in baseline laboratory data, or in intraoperative use of RBC or one-year outcome data were observed between DBD and cDCD recipients. CONCLUSIONS: cDCD with NRP is not associated with increased RBC transfusion. No differences in graft and patient survival between cDCD and DBD were found. Donors after controlled circulatory death with NRP can increasingly be utilized with safety, improving the imbalance between organ donors and the ever-growing demand.

Intra-articular injections of hyaluronan solutions of different elastoviscosity reduce nociceptive nerve activity in a model of osteoarthritic knee joint of the guinea pig.

OBJECTIVE: To study in guinea pigs knee joints the effects of intra-articular injection of HYADD 4-G (Fidia-Farmaceutici), a novel hyaluronan (HA)-derived elastoviscous material and of Hyalgan (Fidia-Farmaceutici), a HA product with very low viscoelasticity, on movement-evoked nociceptor impulse activity from normal and inflamed knee joints. DESIGN: Nociceptor impulse activity was recorded from single Adelta and C fibers of the medial articular nerve either under control conditions or after induction of an experimental knee joint osteoarthritis (OA) by partial medial menisectomy and transection of the anterior cruciate ligament (PMM-TACL). The stimuli consisted of standardized innocuous and noxious inward and outward rotations of the tibia against the femur of 50s duration, repeated every 5min for 1.5h. RESULTS: The number of movement-evoked impulses was significantly augmented 1 day and 1 week after PMM-TACL compared with intact knee joint. The enhanced impulse response to joint movements 1 week following surgery was attenuated by repeated intra-articular injection of HYADD 4-G and even more prominently by Hyalgan. CONCLUSIONS: HA products have a reducing action on joint nociceptor discharges that appears to depend predominantly on their role as an elastoviscous filter associated with their rheological properties, but also on a chemical effect on sensitized nociceptive terminals of inflamed joint tissues, possibly linked to the HA concentration.

Arginine-rich peptides are blockers of VR-1 channels with analgesic activity.

Vanilloid receptors (VRs) play a fundamental role in the transduction of peripheral tissue injury and/or inflammation responses. Molecules that antagonize VR channel activity may act as selective and potent analgesics. We report that synthetic arginine-rich hexapeptides block heterologously expressed VR-1 channels with submicromolar efficacy in a weak voltage-dependent manner, consistent with a binding site located near/at the entryway of the aqueous pore. Dynorphins, natural arginine-rich peptides, also blocked VR-1 activity with micromolar affinity. Notably, synthetic and natural arginine-rich peptides attenuated the ocular irritation produced by topical capsaicin application onto the eyes of experimental animals. Taken together, our results imply that arginine-rich peptides are VR-1 channel blockers with analgesic activity. These findings may expand the development of novel analgesics by targeting receptor sites distinct from the capsaicin binding site.

Responses of nerve fibres of the rat saphenous nerve neuroma to mechanical and chemical stimulation: an in vitro study.

The response of neuroma nerve endings to different stimuli was studied in a saphenous nerve neuroma preparation in vitro. Electrical activity was recorded from 141 single fibres dissected of saphenous nerve. One-third (27 %) displayed spontaneous activity. Based on their response to mechanical and chemical stimuli, neuroma nerve fibres were classified as mechanosensory fibres (47.5 %), mechanically insensitive chemosensory fibres (17.0 %), polymodal nociceptor fibres (28.4 %) and unresponsive fibres (7.1 %). Mechanosensory and polymodal neuroma endings responded to von Frey hair stimulation either with a few impulses (phasic units) or a sustained discharge (tonic units). Polymodal units were additionally activated by at least one of the following stimuli: acidic solutions; a combination of bradykinin, prostaglandin E2, serotonin, substance P and histamine (all at 1 microM) plus 7 mM KCl (inflammatory soup); 600 mM NaCl and capsaicin. Low pH solutions increased the firing discharge of polymodal endings proportionally to the proton concentration. The 'inflammatory soup' evoked a firing response characterized by the absence of tachyphylaxis, which appeared when its components were applied separately. Both stimuli sensitized polymodal fibres to mechanical stimulation. Hypertonic NaCl (600 mM) and capsaicin (3.3 mM) induced a prolonged discharge that outlasted the stimulus duration. Mechanically insensitive chemosensory neuroma fibres exhibited responses to chemical stimuli analogous to polymodal fibres. They became mechanically sensitive after chemical stimulation. These findings show that neuroma nerve endings in the rat saphenous nerve neuroma in vitro are functionally heterogeneous and exhibit properties reminiscent of those in intact mechanosensory, polymodal and 'silent' nociceptor sensory afferents, including their sensitization by algesic chemicals.

Effects of oleoresin capsicum pepper spray on human corneal morphology and sensitivity.

PURPOSE: To examine the potential harmful effects on corneal structure, innervation, and sensitivity of a spray containing the neurotoxin capsaicin (oleoresin capsicum, OC). METHODS: Ten police officers who volunteered for the study were exposed to OC. Clinical signs were assessed. Corneal sensitivity was measured using a Cochet-Bonnet or a noncontact esthesiometer that provides separate measurements of mechanical, chemical, and thermal sensitivity. Tear fluid nerve growth factor (NGF) was measured. Corneal cell layers and subbasal nerves were examined by in vivo confocal microscopy. The subjects were examined before application and 30 minutes, 1 day, 1 week, and 1 month after OC exposure. RESULTS: OC spray produced occasional areas of focal epithelial cell damage that healed within 1 day. Each eye showed conjunctival hyperemia and in two subjects, mild chemosis. All except one eye had unchanged best corrected visual acuity (BCVA). A transient decrease (day 1) of mechanical sensitivity was observed with the Cochet-Bonnet esthesiometer. With the gas esthesiometer, mechanical sensitivity remained below normal values for 7 days. Chemical sensitivity to CO2 was high for as much as 1 day and decreased below normal 1 week later, whereas sensitivity to cold was unaffected. Two subjects had measurable tear NGF that increased after exposure. Basal epithelial cell morphology suggested temporary corneal epithelial swelling, whereas keratocytes, endothelial cells, and subbasal nerves remained unchanged. CONCLUSIONS: Although OC causes immediate changes in mechanical and chemical sensitivity that may persist for a week, a single exposure to OC appears harmless to corneal tissues. The changes are possibly associated with damage of corneal nerve terminals of mainly unmyelinated polymodal nociceptor fibers.

c-Jun expression after axotomy of corneal trigeminal ganglion neurons is dependent on the site of injury.

The proto-oncogene c-Jun has been implicated in the control of neuronal responses to injury and in axonal growth during regenerative processes. We have investigated the expression of c-Jun during normal terminal remodelling in trigeminal ganglion neurons innervating the cornea and after acute injury of epithelial nerve terminals or parent axons. Remodelling and rearrangement, or damage limited to corneal epithelium endings, was not a trigger for activation of c-Jun expression. However, injury of parent axons in the stroma or in the orbital ciliary nerves induced c-Jun expression in 50% of the population of corneal neurons, which included all of the large myelinated and 20% of the small neuropeptide-containing corneal neurons. This suggests that c-Jun expression in trigeminal ganglion neurons is not associated with normal remodelling or regeneration of peripheral nerve terminals, and that it takes place only when parent axons are injured. A substantial number of damaged neurons do not express c-Jun, indicating that in primary sensory neurons, injury and regeneration may not always be coupled to the expression of this proto-oncogene.

Corneal innervation and sensitivity to noxious stimuli in trkA knockout mice.

Most primary sensory neurones depend on neurotrophins for survival. Mutant mice in which TrkA, the high-affinity receptor for nerve growth factor (NGF), has been inactivated lack nociceptive neurones in sensory ganglia and do not respond to noxious stimuli. The cornea of the eye is innervated by trigeminal neurones that are activated by noxious mechanical, thermal and chemical stimuli. In the human cornea, these stimuli evoke only sensations of pain. We have analysed the innervation pattern and the response to noxious stimulation of the cornea of trkA (-/-) mutant mice. Corneal nerves were stained with the gold chloride impregnation method. Corneal sensitivity to noxious stimuli was assessed by counting blinking movements evoked by von Frey hairs, topical application of saline at different temperatures and application of acetic acid and capsaicin at different concentrations. In the cornea of trkA (-/-) mutant animals, we observed a drastic reduction in the number of nerve trunks and branches in the corneal stroma. Furthermore, quantitative analysis of the number of thin nerve terminals revealed a marked decrease in the corneal epithelium of trkA (-/-) mice when compared to those present in wild type and trkA (+/-) animals. The blinking response of trkA (-/-) mice to mechanical, thermal and chemical noxious stimuli was also significantly reduced. These results indicate that the population of corneal sensory neurones is markedly depleted in trkA (-/-) mutant mice. However, a small portion of corneal sensory neurones survive in these mice suggesting that they may be NGF independent. On the basis of our results, we propose that these surviving cells are polymodal nociceptive neurones, sensitive to mechanical stimulation, noxious heat and acid.

Cutting seton versus two-stage seton fistulotomy in the surgical management of high anal fistula.

BACKGROUND: The aim of this study was to compare the clinical results obtained with the cutting seton and the two-stage seton fistulotomy (TSSF) in the surgical management of high anal fistula. METHODS: The case records of 59 patients with high anal fistula of cryptoglandular origin treated with cutting seton (n = 12) or TSSF (n = 47) over a 5-year period were retrospectively reviewed. There was no difference between the groups in age, sex distribution, or estimated percentage of anal sphincter involved by the fistula. Follow-up was by a mailed questionnaire inquiring about fistula recurrence, incontinence, and degree of satisfaction. Mean follow-up was similar in both groups (27 months for cutting seton versus 33 months for TSSF). Comparisons were made by Student t and chi 2 tests, as required. RESULTS: There were no differences in the rate of fistula recurrence between the groups treated with cutting seton or TSSF (one of 12 versus four of 47), difficulty holding gas (six of 12 versus 25 of 47), underwear staining (six of 12 versus 18 of 47), stool incontinence (three of 12 versus 12 of 27), overall incontinence (eight of 12 versus 31 of 47) and mean incontinence score (4.9 versus 4.2). The fistula healing time and degree of satisfaction with the operation were not significantly different between the groups. One-half of the patients treated by TSSF had the seton removed under general or epidural anaesthesia. CONCLUSION: Both techniques are equally effective in eradicating the fistula, and both are associated with a similar rate of incontinence.

Reduction by antiinflammatory drugs of the response of corneal sensory nerve fibers to chemical irritation.

PURPOSE: Nonsteroidal antiinflammatory drugs (NSAIDs) have been applied topically to reduce ocular pain caused by corneal injury or anterior segment surgery. The authors investigated whether the analgesic effects of the NSAIDs diclofenac, indomethacin, and flurbiprofen and of the calcium channel antagonist diltiazem on corneal pain are mediated by a reduction of nerve activity in corneal polymodal nociceptive fibers. METHODS: Impulse activity of single A-delta and C corneal nerve fibers was recorded from the ciliary nerves of anesthetized cats. Polymodal units were identified by their response to both touching with the Cochet-Bonnet esthesiometer and to acidic stimulation with 30-second pulses of 80% or 98.5% CO2 or 60 microl of 10 mM acetic acid, applied to the corneal receptive area. Ongoing impulse activity, firing responses to CO2 or acetic acid, and mechanical threshold of single fibers were recorded before and at various times (5 to 90 minutes) after topical application of 0.1% sodium diclofenac, 0.03% sodium flurbiprofen, 0.1% indomethacin, and 0.045% diltiazem hydrochloride or of their vehicles. RESULTS: Indomethacin, diclofenac, and flurbiprofen, in decreasing order of potency, gradually reduced the mean frequency of the impulse response of corneal polymodal nerve fibers evoked by CO2 stimuli. The progressive increase of ongoing activity, observed in vehicle-treated eyes after repeated CO2 stimulation was also prevented by NSAIDs. Diltiazem also attenuated the response to CO2 for a shorter period of time and with a faster time course. The mechanical threshold of corneal polymodal fibers was not affected by treatment with any of these drugs. CONCLUSIONS: Indomethacin, diclofenac, and flurbiprofen, as well as the calcium antagonist diltiazem, diminish the responsiveness of corneal polymodal nociceptors to chemical stimuli. This appears to be caused, in part, by a direct effect of these drugs on the excitability of polymodal nerve endings, but also by an inhibition by NSAIDs of the formation of cyclooxygenase products such as prostaglandins, thus reducing the enhanced responsiveness of nociceptors caused by local release of arachidonic acid metabolites from injured cells.

Facility changes mediated by cAMP in the bovine anterior segment in vitro.

The aim of this study was to investigate the influence of substances that increase intracellular cAMP levels on the aqueous humor outflow facility (C) of isolated bovine anterior segments. Anterior segments were perfused in vitro at a constant pressure of 10 mmHg for 270 min with a general protocol as follows: 90 min control perfusion with DMEM, 90 min of experimental perfusion with DMEM containing the test drug(s), and 90 min of postdrug-perfusion with DMEM. C was calculated as the ratio between the rate of medium inflow (microliter/min) and the perfusion pressure (mmHg). Anterior segments can be perfused in vitro for up to 5 hr without significantly modifying their C. The addition of epinephrine, forskolin, dibutyryl-cAMP or isobutylmethylxanthine to the control perfusion medium elicited a significant increase of C. If, during isobutylmethylxanthine perfusion, forskolin or epinephrine was added, C increased significantly. Finally, perfusion with indomethacin prior to addition of epinephrine prevented the increase of C induced by epinephrine. Epinephrine, the adenylate cyclase activator forskolin, the cAMP analog dibutyryl-cAMP, and the phosphodiesterase inhibitor isobutylmethylxanthine all increase aqueous facility. It seems reasonable to suspect that the cAMP system is involved in epinephrine's effects on bovine trabecular meshwork cells. Moreover, the complete inhibition by indomethacin of the outflow facility increase induced by epinephrine suggests that prostaglandins may be involved in the outflow facility mechanisms related to adrenoreceptor stimulation of trabecular meshwork cells.

Anal fistula surgery. Factors associated with recurrence and incontinence.

PURPOSE: This study was undertaken to assess results of surgery for fistula-in-ano and identify risk factors for fistula recurrence and impaired continence. METHODS: We reviewed the records of 624 patients who underwent surgery for fistula-in-ano between 1988 and 1992. Follow-up was by mailed questionnaire, with 375 patients (60 percent) responding. Mean follow-up was 29 months. Fistulas were intersphincteric in 180 patients, transsphincteric in 108, suprasphincteric in 6, extrasphincteric in 6, and unclassified in 75. Procedures included fistulotomy and marsupialization (n = 300), seton placement (n = 63), endorectal advancement flap (n = 3), and other (n = 9). Factors associated with recurrence and incontinence were analyzed by univariate and multivariate regression analysis. RESULTS: The fistula recurred in 31 patients (8 percent), and 45 percent complained of some degree of postoperative incontinence. Factors associated with recurrence included complex type of fistula, horseshoe extension, lack of identification or lateral location of the internal fistulous opening, previous fistula surgery, and the surgeon performing the procedure. Incontinence was associated with female sex, high anal fistula, type of surgery, and previous fistula surgery. CONCLUSIONS: Surgical treatment of fistula-in-ano is associated with a significant risk of recurrence and a high risk of impaired continence. Degree of risk varies with identifiable factors.

The Hartmann procedure. First choice or last resort in diverticular disease?

OBJECTIVE: To critique changing trends in the surgical management of diverticular disease. DESIGN: Case series. Two hundred twenty-seven consecutive patients required surgery for diverticular disease from 1988 to 1993. Patient records were reviewed retrospectively. Operative procedures included primary resection in all patients with either anastomosis, anastomosis with proximal ileostomy, or the Hartmann procedure. Morbidity, mortality, and length of stay were then compared with each operative procedure and stage of disease. Patients were categorized according to the following pathologic stages: stage 0, no inflammation; stage I, chronic inflammation; stage II, acute inflammation with or without microabscesses; stage III, pericolonic or mesenteric abscess; stage IV, pelvic abscess; and stage V, purulent or feculent peritonitis. SETTING: A university hospital and private affiliated hospitals in a large metropolitan area. MAIN OUTCOME MEASURES: Study outcome parameters included mortality, morbidity, length of hospital stay, and leak rates. These outcomes were then compared with different disease stages and treatments. RESULTS: Mean patient age was 66 years (range, 25-98 years). Male-female ratio was 84:143. Mean follow-up was 23 months (range, 1-132 months). There were 50 fistulas: 24 colovesical, 21 colovaginal, 3 colocolonic, 1 coloenteric, and 1 colouterine. Surgery was categorized as elective for 196 patients (86%), urgent for 12 (5%), and emergent for 19 (8%). Primary resection was performed in all cases. Primary anastomosis was performed in 200 patients (88%), 183 without and 17 with proximal diversion. Twenty-seven patients (12%) underwent a Hartmann procedure with colostomy; 19 patients (70%) have since undergone colostomy closure. Morbidity occurred in 52 patients (23%), including 4 anastomotic leaks (2%). There were 3 perioperative deaths (1%). Mean length of initial hospital stay was 11 days (range, 4-59 days). Length of stay was 5 days (range, 4-7 days) for ileostomy closure (7% morbidity) and 13 days (range, 7-35 days) for the colostomy closure after the Hartmann procedure (33% morbidity). CONCLUSIONS: Primary resection is virtually always possible in complicated diverticular disease. Primary anastomosis, with or without proximal diversion, is safe for patients with no abscesses or localized abscesses and should be considered on an individual basis for patients with pelvic abscesses and peritonitis. Colostomy closure after the Hartmann procedure is associated with significant length of hospitalization and morbidity and leaves one third of patients with permanent stomas.

C-Fos expression in trigeminal nucleus neurons after chemical irritation of the cornea: reduction by selective blockade of nociceptor chemosensitivity.

The distribution and number of trigeminal brainstem and higher order sensory neurons expressing the protein product of the proto-oncogene c-fos after noxious stimulation of the cornea was studied in the rat using immunocytochemistry. The possibility that attenuation of nociceptive messages from the cornea by diltiazem reduced Fos-like immunoreactivity of spinal trigeminal neurons was also examined. A group of animals were killed 2-3 h after corneal stimulation. One cornea was stimulated with: a drop of 10 mM acetic acid; with acid plus mechanical scratching of the corneal epithelium; or with a drop of saline of 56 degrees C. Half of the animals treated with acid had been pretreated ipsilaterally with topical diltiazem (10 mM). Control rats received either saline in one eye or no treatment. Another group of animals were killed 7-8 h after stimulation with acetic acid. Fos-like immunoreactive neurons were counted in serial brainstem sections using an anti-Fos primary antiserum and processed according to the avidin-biotin complex method. In rats killed 2-3 h after corneal stimulation with acid, heat, or acid plus mechanical injury, labelled neurons were found in laminae I and II of the intermediate zone between caudalis and interpolaris subnuclei of the ipsilateral spinal trigeminal nucleus and, in a reduced number, in the symmetrical zones of the contralateral side. In animals stimulated with noxious heat or combined mechanical and chemical injury, a few scattered cells were also labelled in the ipsilateral junction between the cervical spinal cord and the caudalmost part of the trigeminal subnucleus caudalis. In rats killed 7 h after stimulation with acid, stained neurons were observed in the same areas of the trigeminal nucleus as in rats killed at shorter times, but in lower numbers; in these animals, no immunoreactive cells were found in deeper laminae or in higher sensory relay nuclei. Pretreatment with diltiazem significantly reduced the number of cells of the spinal trigeminal nucleus labelled after corneal stimulation with acid. The results indicate that brief noxious stimulation of the cornea evoke expression of c-Fos in neurons of the spinal trigeminal complex. Diminution by diltiazem of the number of immunoreactive neurons activated by corneal irritation suggests that this drug, by reducing chemosensitivity of nociceptive terminals, decreases nociceptive inflow to central nervous structures involved in ocular pain perception.

Irritation of the anterior segment of the eye by ultraviolet radiation: influence of nerve blockade and calcium antagonists.

The aim of this investigation was to determine the influence on anterior segment inflammation elicited by UV radiation, of ocular denervation and pharmacological blockade of sensory nerve fibers with capsaicin, tetrodotoxin and calcium antagonists. Both eyes of pigmented rabbits were exposed for 5 min to UV radiation (254 nm); 24 h later, inflammatory signs were evaluated by biomicroscopy of the corneal epithelium, the stroma and the endothelium and scored from 0 to 4. Conjunctival vasodilation and miosis were also assessed. Two weeks before UV exposure, a group of rabbits received a retrobulbar injection of ethanol or of 1% capsaicin. Intact, capsaicin-treated and alcohol-denervated animals were treated topically, prior to UV exposure, with tetrodotoxin (0.78 mM) and the calcium antagonists diltiazem (1-28 mM) and nifedipine (10 mM). UV radiation produced at 24 h signs of corneal irritation, conjunctival hyperemia, miosis and elevated protein content of the aqueous humor. Retrobulbar injection of 99% alcohol or 1% capsaicin did not diminish significantly the inflammation of tissues directly exposed to UV radiation, although extension of inflammatory signs to unaffected areas was prevented. Pre-treatment of normal and denervated eyes with diltiazem attenuated UV-induced eye irritation signs at concentrations of 10 mM or over. The effect was less pronounced with tetrodotoxin and was not obtained with nifedipine. These findings suggest that the contribution of a neurogenic mechanism to anterior segment inflammation induced by UV exposure is modest. They also show that high concentrations of diltiazem, but not of nifedipine, effectively reduced inflammation of the anterior segment of the eye evoked by UV radiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional assessment of ileal pouch-anal anastomotic techniques.

BACKGROUND: Recent advances in ileal pouch-anal anastomotic (IPAA) technique include the substitution of a double stapled anastomosis for a mucosectomy and hand-sewn pouch-anal anastomosis, and the use of staples to construct a "J" shaped pouch rather than a hand-sewn "S" pouch in most cases. METHOD: To determine the impact these technical changes have had on pouch function, 235 IPAA patients with 15 to 155 months of follow-up (mean 70 months) were interviewed by telephone concerning pouch function and quality of life. Categorical responses were then evaluated by contingency table analysis to detect differences between mucosectomy (n = 157) and nonmucosectomy (n = 80) groups, and between J pouch (n = 50), S pouch with mucosectomy (n = 137), and S pouch nonmucosectomy (n = 30) subgroups. An index encompassing nine functional measures was used to quantify the overall impact of technique changes (optimal score 100). RESULTS: Stool frequency for mucosectomy patients was 7.2 movements/24 hours, compared to 7.1 for nonmucosectomy patients. Elimination of a mucosectomy dramatically reduced nocturnal major incontinence (P < 0.001), nocturnal minor incontinence (P < 0.001), daytime minor incontinence (P = 0.03), and day-time pad use (P = 0.002). Nonmucosectomy patients had a better functional index score than had patients with an S pouch, even when only data from nonmucosectomy patients were analyzed (J = 95.5, S = 91.8, P = 0.009). CONCLUSIONS: Avoidance of a mucosectomy in the performance of an ileal pouch-anal anastomosis does not influence stool frequency but does significantly improve fecal continence and introduces no detectable morbidity associated with the retained rectal mucosa.

Breakage of Knowles pins used for femoral neck fractures.

We report the breakage of multiple Knowles pins in two patients with fractures of the femoral neck. The break occurred at the junction of the threaded and smooth sections of the pins before consolidation of the fracture.

Chronic stimulation of ocular sympathetic fibers in unanesthetized rabbits.

The goal of this study was to devise a technique to implant permanent electrodes in the cervical sympathetic trunk, to stimulate the ocular adrenergic fibers for periods of hours or days in awake, unrestrained rabbits. Electrodes were made of a silver wire soldered to a multistranded wire and enclosed in silicone. Two of these electrodes were wrapped around the preganglionic sympathetic nerve, their leads emerging through a hole in the back of the neck. Success of the procedure was confirmed by the mydriasis elicited by electrical stimulation of the nerve following surgery; threshold voltages for the pupillary response varied between 5-10 volts. In eight rabbits, suprathreshold sympathetic stimulation was performed on the following days by means of a portable stimulator using increasing frequencies (1, 3, 5, 8, and 10 Hz) during a 20-hr period. Dilation of the ipsilateral pupil and vasoconstriction in the ear, measured by the fall in temperature of the ear's surface, was observed as long as stimulation was maintained. Both effects were proportional to the frequency of stimulation. Maximal mydriasis was obtained at 8 Hz, whereas full vasoconstriction was elicited with 5 Hz. Intraocular pressure, measured in 10 rabbits with a Perkins tonometer at the end of a 24-hr stimulation period, did not differ from pre-stimulation values. It was concluded that chronic stimulation of the sympathetic nerve allows to maintain known levels of adrenergic activity in the eye, and may be a useful method to study the actions of the adrenergic system on various ocular functions in unanesthetized animals.