PubMed Health⌕ Search

Biomedical subjects

I Mackenzie

Publications and source records attributed to I Mackenzie.

At least 55 records · Page 3Linked to original sources

Preoperative skin preparation and surgical outcome.

The use of antiseptics in surgery from Lister to the present day is described. A review of current procedures for preoperative preparation for surgery is given; and some data showing that the effect of chlorhexidine on skin flora is persistent is recorded.

Anti-Infective Agents, Local↗

Air gun pellet embolism.

Air gun injuries are traditionally regarded as trivial unless they penetrate vulnerable superficial organs such as the eye, and demands for tighter controls have been largely disregarded. We report a unique complication of a penetrating air gun pellet which emphasises the potential lethal capability of these weapons.

Adolescent↗

A dentonasal deformity.

A case of an impacted mesiodens that produced a marked nasal deformity and a deviated nasal septum is discussed.

Adult↗

An organ culture model for examining epidermal desquamation.

The use of organ cultures of mouse ear skin for examining mechanisms of stratum corneum shedding has been investigated. The formation and loss of stratum corneum cells was assessed by electron microscopic autoradiography and from counts of stratum corneum cell layers taken from sections of plastic-embedded specimens. Using media supplemented with cortisone, there was a linear accumulation of stratum corneum cell layers and the rate of epidermal cell formation corresponded approximately to that in vivo. Cells that accumulated at the stratum corneum surface were loose and could consistently be removed by treatment with detergent and ultrasonication indicating the persistence of shedding mechanisms in vitro.

Animals↗

Neuropeptide action on the guinea-pig bladder; a comparison with the effects of field stimulation and ATP.

A comparison was made between the effects of several neuropeptides and ATP as possible mediators of the non-adrenergic, non-cholinergic excitatory response in detrusor strips from the guinea-pig urinary bladder. Both substance P and vasoactive intestinal polypeptide produced contractions of the guinea-pig bladder, but the form of the atropine-resistant neurogenic excitation was mimicked more precisely by ATP. Neither methionine enkephalin nor leucine enkephalin had a prominent direct action on the smooth muscle (up to 100 microM) and did not significantly modify the cholinergic or non-cholinergic components of the response elicited by field stimulation. A proteolytic enzyme, chymotrypsin (10 U/ml), antagonised the excitatory effect of substance P, but not that of the non-adrenergic, non-cholinergic excitatory response or ATP. The slow excitation elicited by a high concentration of vasoactive intestinal polypeptide (10 microM), in contrast to responses elicited by ATP or field stimulation, was attenuated by preincubation with the structurally related polypeptide PHI, which was itself inactive (up to 10 microM). The present observations argue against a role for the peptides studied as neuromuscular transmitters in the detrusor but do not preclude such a role for ATP.

Adenosine Triphosphate↗

Three year follow-up study on the treatment of first and second degree hemorrhoids by sclerosant injection or rubber band ligation.

Two groups of 18 patients undergoing sclerosant injection or rubber band ligation for first or mild, second degree hemorrhoids have been followed-up at three years after the initial treatment. Following sclerosant injections, four of 18 patients initially presenting with bleeding per rectum did not have further episodes of bleeding within the three year follow-up period compared with 13 of 17 treated with rubber band ligation. The other symptoms of pain or discomfort, pruritus ani and soiling were not present with sufficient frequency to allow specific evaluation. Results of this study demonstrate that rubber band ligation produces better long term results than does sclerosant injection in treating bleeding, the principal symptom, of first and mild, second degree hemorrhoids.

Adult↗

The importance of pain, pruritus and soiling as symptoms of haemorrhoids and their response to haemorrhoidectomy or rubber band ligation.

Bowel habit, anal pain or discomfort, pruritus ani and faecal soiling have been assessed in 82 patients with uncomplicated, prolapsing haemorrhoids before and after successful treatment (improvement in rectal bleeding and haemorrhoidal prolapse) by haemorrhoidectomy or rubber band ligation. An age and sex-matched control group of patients without haemorrhoids was similarly assessed. The bowel habit of the haemorrhoid group was not different from that of the control population. Pain or discomfort, pruritus and faecal soiling were much commoner in the pretreatment haemorrhoid group, compared to controls. Treatments designed to abolish rectal bleeding and prolapse (the cardinal symptoms of haemorrhoids) also reduced the incidence of these three symptoms. Only anal pain or discomfort, however, was reduced to the incidence found in the control group. Haemorrhoidectomy and rubber band ligation appeared equally effective in controlling all three symptoms. It is concluded that anal pain or discomfort, pruritus ani and faecal soiling are common symptoms of uncomplicated haemorrhoids and that they are abolished in the majority of patients by successful treatment for rectal bleeding and haemorrhoidal prolapse.

Adult↗

Comparison of rubber band ligation and sclerosant injection for first and second degree haemorrhoids-- a prospective clinical trial.

Fifty patients with first or mild second degree haemorrhoids were randomly allocated to sclerosant injection (26) or rubber band ligation (24). One year after treatment 24 injection and 22 rubber band ligation patients were assessed. All patients presented with rectal bleeding; injection relieved 14 and rubber band ligation relieved 17 of this symptom (N.S.). Three of seven patients with prolapsing haemorrhoids who had sclerosant injections and five of seven who had rubber band ligation were relieved of this prolapse. However, a further six patients in the injection group developed prolapse for the first time during the one year follow-up period (p less than 0.05). Rubber band ligation relieved anal pain in 10 out of 14 patients whereas injection relieved only one patient of this symptom (p less than 0.05). Neither treatment influenced pruritus ani or faecal soiling. Although rubber band ligation caused more treatment discomfort, it is an effective management for first and mild second degree haemorrhoids and it should be considered as the procedure of choice.

Adult↗

Evidence against vasoactive intestinal polypeptide being the non-adrenergic, non-cholinergic inhibitory transmitter released from nerves supplying the smooth muscle of the guinea-pig taenia coli.

Vasoactive intestinal polypeptide (VIP), located within intrinsic neurones of the guinea-pig taenia coli, has been proposed as a neurotransmitter which may mediate certain non-adrenergic, non-cholinergic effects within the gastrointestinal tract. The relaxation of the taenia coli produced by exogenous VIP has a longer latency and time to maximum than the relaxation which is obtained during electrical stimulation of the non-adrenergic, non-cholinergic nerves. The responses to exogenous VIP (0.03-1 microM) were abolished by the proteolytic enzyme alpha-chymotrypsin (1 U/ml), whereas there were no statistically significant changes in the inhibitory responses to intramural nerve stimulation (0.1-5 Hz) or exogenous ATP (0.03-100 microM), which closely mimics the nerve-mediated response. Apamin is a neurotoxin which prevents the increase in K+ conductance associated with the inhibitory junction potential produced by stimulation of the non-adrenergic, non-cholinergic inhibitory nerves. In the presence of apamin (0.005-1 microM) the responses to intramural nerve stimulation and exogenous ATP were significantly antagonised, and often converted to contractile responses. The VIP-induced relaxations during apamin treatment were not significantly decreased. These results suggest that VIP is unlikely to be the transmitter released from the non-adrenergic, non-cholinergic nerves of the guinea-pig taenia coli, and are consistent with the view that these nerves are purinergic in nature.

Adenosine Triphosphate↗

Comparison of rubber band ligation and haemorrhoidectomy for second- and third-degree haemorrhoids: a prospective clinical trial.

One hundred patients with second- or third-degree haemorrhoids were randomly allocated to haemorrhoidectomy (50) or rubber band ligation (50). Forty-two in each group presented with rectal bleeding; haemorrhoidectomy relieved 36 and rubber band ligation relieved 31 of this symptom. All patients had prolapsing haemorrhoids at presentation. One year after treatment 45 haemorrhoidectomy and 43 rubber band ligation patients were assessed. Haemorrhoidectomy relieved 44 of 45 patients and rubber band ligation relieved 34 of 43 (P < 0.05). Haemorrhoidectomy caused pain in all cases, lasting for more than 48 h in 35. Rubber band ligation was painless in 5 and produced pain for more than 48 h in 15. Mean time off work was 32 days for haemorrhoidectomy and 3 days for rubber band ligation (P < 0.001). Rubber band ligation as an outpatient procedure is an effective treatment for second- and third-degree haemorrhoids and should be considered before recourse to surgery.

Adult↗

Demonstration of actin in oral epithelial cells.

Two human sera with antibodies against smooth muscle were used to investigate the distribution of actin in moving oral epithelial cells by immunocytochemical methods. Epithelial outgrowths from explants of rat and human oral mucosa showed a constant positive staining in the peripheral parts of the marginal cells but not in the more central parts of the epithelial sheet. This is in agreement with theories of the importance of the marginal cells in the migratory behavior of the epithelial outgrowth. Subcultured epithelial cells from the human explants showed positive staining of fine fibers in the cytoplasm. During healing of experimental oral wounds from humans and monkeys actin fibers could be demonstrated in only one of 18 cases in the epithelial cells adjacent to the wound, though positive staining of various cells was seen in the underlying tissue. This is in contrast to the evidence presented in previous studies of cells taking part in the re-epithelialization process.

Actins↗

Long term cimetidine in the management of severe duodenal ulcer dyspepsia.

Sixty patients who had been referred for elective ulcer surgery, and in whom a remission had been induced, entered a prospective double blind controlled trial of a single daily dose of 400 mg of cimetidine given at bedtime, or placebo. Eighty per cent of patients receiving placebo suffered symptomatic relapse and recurrence of duodenal ulceration at endoscopy within 6 months. The mean interval to relapse was 10 weeks. On the other hand, only 27 percent of patients had a recurrence during the 6-month period on low dose cimetidine therapy. No significant toxic or other side effects which could be attributed to the drug were observed.

Adult↗