Search PubMed⌕ Search

Biomedical subjects

M C Anderson

Publications and source records attributed to M C Anderson.

At least 37 records · Page 2Linked to original sources
PubMed1996

Glandular lesions of the cervix-cytological and histological correlation.

In this retrospective review we assessed the frequency with which atypical glandular cells in cervical smears predict cervical glandular lesions. Asymptomatic patients (n=34) with one or more smears showing atypical glandular cells aand subsequent histopathological assessment were studied. Independent cytological and histological review was undertaken. Cytological review confirmed atypical glandular cells in 29 cases, 17 of which had coexisting squamous dyskaryosis. Histological review of these 29 cases revealed glandular neoplasia in 13 (45%) and microglandular hyperplasia (MEH) in an additional four (14%). Initial reporting had underestimated the prevalence of glandular neoplasia.

Adenocarcinoma↗
PubMed1995

Glandular lesions of the cervix: diagnostic and therapeutic dilemmas.

The term 'glandular lesions' applies mainly to the spectrum of intraepithelial neoplasia affecting the glandular epithelium of the cervix, but consideration must also be given to non-neoplastic disorders. Various systems of terminology are used, the most satisfactory being low grade and high grade CIGN. The criteria for histological diagnosis are quite well defined, although the distinctions between low grade and high grade lesions and between intraepithelial and early invasive disease can be problematic. Although many cases are initially diagnosed on smears, the cytological diagnosis can also be difficult, particularly when squamous lesions are also present, as happens in about 50% of cases. Both histologically and cytologically, the differential diagnosis between CIGN and non-neoplastic changes must be made. Treatment for high grade lesions has traditionally been hysterectomy, but there is evidence that conization with careful cytological follow-up may be safe in certain circumstances. Women with low grade lesions are generally managed in the same way; the role of cytological surveillance of women with mild glandular abnormalities in their smear is not clear. Although there is evidence to substantiate the belief that CIGN is a precursor of adenocarcinoma of the cervix, very little is known of the natural history of these lesions, their relations to one another and the significance of the low grade abnormalities. This uncertainty hampers a rational approach to management.

Biopsy↗
PubMed1995

On the status of inhibitory mechanisms in cognition: memory retrieval as a model case.

Theories of cognition frequently assume the existence of inhibitory mechanisms that deactivate mental representations. Justifying this assumption is difficult because cognitive effects thought to reflect inhibition can often be explained without recourse to inhibitory processes. This article addresses the uncertain status of cognitive inhibitory mechanisms, focusing on their function in memory retrieval. On the basis of a novel form of forgetting reported herein, it is shown that classical associative theories of interference are insufficient as accounts of forgetting and that inhibitory processes must be at work. It is argued that inhibitory processes are used to resolve computational problems of selection common to memory retrieval and selective attention and that retrieval is best regarded as conceptually focused selective attention.

Adult↗
PubMed1994

Estimation of monoamine oxidase concentrations in soluble and membrane-bound preparations by inhibitor binding.

A modification of the [3H]-pargyline labelling technique is presented for determining the active-site concentration of monoamine oxidase in soluble preparations. Kinetic considerations show that the rate of reaction of MAO-A with low concentrations of free pargyline will be very much slower than that of MAO-B. Failure to use adequate reaction times for the concentration of pargyline added can lead to gross underestimation of the quantity of MAO-A present.

Animals↗
PubMed1994

Remembering can cause forgetting: retrieval dynamics in long-term memory.

Three studies show that the retrieval process itself causes long-lasting forgetting. Ss studied 8 categories (e.g., Fruit). Half the members of half the categories were then repeatedly practiced through retrieval tests (e.g., Fruit Or_____). Category-cued recall of unpracticed members of practiced categories was impaired on a delayed test. Experiments 2 and 3 identified 2 significant features of this retrieval-induced forgetting: The impairment remains when output interference is controlled, suggesting a retrieval-based suppression that endures for 20 min or more, and the impairment appears restricted to high-frequency members. Low-frequency members show little impairment, even in the presence of strong, practiced competitors that might be expected to block access to those items. These findings suggest a critical role for suppression in models of retrieval inhibition and implicate the retrieval process itself in everyday forgetting.

Humans↗
PubMed1994

Outcome after lateral pancreaticojejunostomy for chronic pancreatitis.

OBJECTIVE: To assess the outcome of lateral pancreaticojejunostomy in patients with chronic pancreatitis. SUMMARY BACKGROUND DATA: Chronic fibrocalcific pancreatitis associated with pancreatic ductal dilation and chronic pain has been managed successfully with lateral pancreaticojejunostomy. Early results, measured by pain relief and postoperative morbidity and mortality, have been excellent; however, long-term follow-up and overall outcome has been less clearly defined in these patients. METHODS: The outcome of 85 patients who had lateral pancreaticojejunostomy was assessed by reviewing hospital inpatient and outpatient records and conducting patient telephone interviews. RESULTS: Of 62 patients who were alive at follow-up, health status was characterized as good in 24%, fair in 31%, and poor in 45%. Alcohol abuse continued in 42% of patients, whereas narcotic use continued in 35%, insulin use continued in 23%, and pancreatic enzyme supplementation continued in 34%. Rehospitalization for recurrent attacks of pancreatitis and pain was necessary in 40% of patients. Six patients required subsequent operations for complications of chronic pancreatitis. Death occurred in 22 patients (26%) and resulted from continued alcohol abuse, progression of chronic pancreatitis, or late complications of the operation in more than one half the cases. CONCLUSIONS: Although lateral pancreaticojejunostomy provided pain relief, had a low morbidity rate, and no early postoperative deaths, long-term outcome was poor based on the patient's health status, continued alcohol and narcotic use, employment status, subsequent hospitalization to treat recurrent pancreatitis or its complications, subsequent operations required for complications of chronic pancreatitis, and postoperative deaths related to comorbid medical conditions or complications of chronic pancreatitis.

Adult↗
PubMed1994

Colonic complications of pancreatitis.

A retrospective review of 296 patients referred for surgical management of pancreatitis from 1964 to 1992 revealed that 18 (6.1%) had colonic complications. Of seven patients with chronic pancreatitis, six developed pancreatocolonic fistulas. One had stenosis of the transverse colon, which resolved after pancreatic cystjejunostomy, three were managed with local fistula excision and simple colon closure, three had segmental colectomy, and in one the fistula closed spontaneously with expectant management. Three patients had concomitant lateral pancreaticojejunostomy, and two had a cystjejunostomy. There were two postoperative complications, but no mortality. Eleven patients had acute necrotizing pancreatitis. Seven developed segmental colonic infarction that required partial colectomy. Four had colonic fistulas, two managed with partial colectomy and colostomy, and two managed nonoperatively. Eleven patients developed major postoperative complications; four died, two from sepsis and multiorgan failure and two from recurrent hemorrhage from a necrotic pancreatic bed. Our findings indicate that the presentation, management, and outcome of colonic complications differ in chronic and acute pancreatitis. In chronic pancreatitis, pancreatocolonic fistula predominated and could be managed either with local excision or segmental resection of the colon with excellent results. Simultaneous surgical correction of associated pancreatic pathology was possible in five patients. In acute necrotizing pancreatitis, colonic infarction secondary to the necrotizing inflammatory process was frequent and required colon resection. There was substantial morbidity and mortality in spite of treatment with colectomy.

Acute Disease↗
PubMed1993

Arterial hemorrhage complicating pancreatic pseudocysts: role of angiography.

Major arterial hemorrhage associated with pancreatic pseudocysts represents a formidable complication with high mortality rates. This study was undertaken to analyze presentation and outcome and to assess the role of angiography in diagnosis and management of this complication. A retrospective review of 180 patients referred for surgical management of pancreatic pseudocysts from 1964 to 1991 identified 13 patients (7.2%) with arterial hemorrhage. Eight patients presented with intracystic hemorrhage, 4 with upper gastrointestinal bleeding, and 1 with intra-abdominal bleeding. Six patients had gastroduodenal artery bleeding, 4 splenic, and 1 each left gastric, right colic, and left gastroepiploic. The site of bleeding was identified with selective visceral angiography in 9 patients; evidence of pseudocyst bleeding was seen in 5 of 7 patients who had contrast-enhanced computerized tomography (CT) scans. Angiographic embolization for control of hemorrhage was used in 6 patients and operative control in 7. Over the past decade, bleeding has been controlled with angiographic embolization in all patients except 1 with massive bleeding due to splenic artery erosion. Average blood loss was less in patients treated with angiographic embolization (6.8 vs 17.5 units, packed red cells, P < .05, Wilcoxon rank sum test). The sole mortality was a patient with cirrhosis treated in 1969. Clinical presentation of pseudocyst bleeding is variable; the underlying cause is usually related to chronic pancreatitis due to alcohol abuse. The dynamic contrast-enhanced CT scan is valuable in demonstrating evidence of pseudocyst bleeding. Accurate diagnosis with dynamic CT scan and angiography and control of bleeding with angiographic embolization has improved the outcome in patients with this complication.

Adolescent↗
PubMed1993

Monoamine oxidase inhibitors and the cheese effect.

The behavior of inhibitors of monoamine oxidase-A (MAO-A) is considered in terms of the possibility of having an effective antidepressant that does not give rise to hypertensive interactions with dietary tyramine. Studies with punch-biopsy samples of human intestine and rat intestinal samples show MAO-A to be the predominant form of the enzyme in both species. Transport studies with everted rat intestinal preparations indicate that tyramine is extensively metabolized during transport through the intestine. Selective inhibition of MAO-A by clorgyline results in a large increase in the amount of unchanged tyramine transported, whereas selective inhibition of MAO-B with L-deprenyl (selegiline) has no significant effect. The behavior of reversible MAO-A inhibitors can significantly reduce, but not entirely eliminate, these effects on the intestinal metabolism of tyramine, but only if the inhibition is competitive in nature.

Animals↗
PubMed1993

Invasive carcinoma of the cervix following local destructive treatment for cervical intraepithelial neoplasia.

OBJECTIVE: To investigate the occurrence of invasive carcinomas following local destructive treatment for cervical intraepithelial neoplasia (CIN) and to evaluate the factors responsible. DESIGN: A multicentre retrospective study. SUBJECTS: Forty-nine women registered with the British Society for Colposcopy and Cervical Pathology from 24 centres throughout Great Britain between 1985 and 1992, who had been treated by local destructive methods for CIN and who subsequently developed invasive carcinoma of the cervix. RESULTS: Of the 49 women whose details were submitted, 42 had squamous cell carcinoma, six adenosquamous carcinoma and one adenocarcinoma. Eight had microinvasive carcinomas (Stage Ia) at the time of diagnosis, 24 had Stage Ib tumours and eight Stages II to IV. Thirteen women have died. Thirty-five women had been treated by laser vaporization, ten by cold coagulator, two by diathermy and two by cryosurgery. In 19 women (39%) the diagnosis of invasive carcinoma was made on the first follow up visit or within one year of treatment. Five patients did not present with invasive disease until more than five years after treatment. CONCLUSIONS: The data presented suggest that many, but not all, of the invasive carcinomas presenting after local destructive treatment for CIN resulted from failure to recognise early invasive disease at the time of the initial assessment. The importance of thorough evaluation before undertaking these forms of treatment is emphasised. The use of excisional procedures should further reduce the small risk of invasive carcinoma developing after treatment for CIN.

Adenocarcinoma↗
PubMed1993

The Royal College of Obstetricians and Gynaecologists micro-invasive carcinoma of the cervix study: preliminary results.

OBJECTIVES: To determine how micro-invasive carcinoma of the cervix is diagnosed and treated in the United Kingdom. To record the frequency of the various pathological features which comprise the histological diagnosis of micro-invasion, and to assess their relevance to outcome. DESIGN: Prospective observational study. SETTING: Hospitals throughout the United Kingdom. SUBJECTS: Two hundred and eighty-six cases were submitted for entry into the study. Following independent review of the histological material 116 cases were excluded: 41 were not accompanied by histological slides for review, 55 had no evidence of invasive disease, 17 had invasive disease greater than FIGO Stage 1a, and three were adenocarcinomas. The remaining 170 cases were registered for the study but follow up was incomplete in 18. This report concerns the 152 women with complete follow up to 1991. RESULTS: The age of the 152 women ranged from 22 to 65 years (median 36 years). In 116 women (76%) the diagnosis was made by cone biopsy (cold knife, loop diathermy, or laser) or wedge biopsy, in 9 women (6%) the diagnosis was made by hysterectomy, and in 27 women (18%) punch biopsy suggested an invasive lesion and subsequent excisional treatment (including radical hysterectomy with node dissection in three) demonstrated micro-invasion. The depth of invasion was up to 3 mm in 142 women (93%) and 3.1 to 5 mm in 10 women (7%). Capillary-like space involvement was present in 12 women (8%). Treatment methods used were local cervical surgery in 79 women (52%), simple hysterectomy in 63 (41%), and radical hysterectomy in 10 (7%). There was only one known recurrence and death due to cervical carcinoma. CONCLUSION: There is no uniformity in the management of micro-invasive carcinoma of the cervix. The frequency of recurrence, lymph metastases, and death is low. Nonradical surgery appears to give satisfactory results.

Adult↗
PubMed1992

Percutaneous catheter drainage compared with internal drainage in the management of pancreatic pseudocyst.

The records of 92 patients with symptomatic pancreatic pseudocysts referred for surgical management over a 27-year period were retrospectively reviewed to compare outcome in 42 patients managed with operative internal drainage procedures (group I) with that in 52 patients managed with computed tomography-directed percutaneous catheter drainage (PCD) (group II). The two groups were similar for patient age, sex, pseudocyst location, and cause. The frequency of antecedent pseudocyst-associated complications was less in group I (16.7 versus 38.5%, p less than 0.05). Seven group I patients and four group II patients had major complications (16.7 versus 7.7%, not significant). Group II mean duration of catheter drainage was 42.1 days, and the drain track infection rate was 48.1%. The frequency of antecedent operative cyst drainage was similar (14.2 versus 13.5%), as was the frequency of subsequent operations for complications related to chronic pancreatitis (9.5 versus 19.2%, not significant). Mortality rate was greater in group I (7.1% versus 0%, p less than 0.05). Pseudocysts can be effectively managed either by open operation with internal drainage or by PCD. Drawbacks of PCD include the controlled external pancreatic fistula and the risk of drain track infection. Percutaneous catheter drainage has the following advantages: (1) low mortality rate, (2) does not require a major operation, (3) does not violate the operative field in cases when subsequent retrograde duct drainage procedures are required. Neither PCD nor internal drainage is definitive, and with either technique subsequent correction of underlying pancreatic pathology may be necessary.

Adult↗
PubMed1992

Changing concepts in the surgical management of pancreatic pseudocysts.

A 27-year experience in the surgical management of 160 patients with pancreatic pseudocysts was reviewed. Sixty-eight patients treated from 1964 to 1981 (Group I) were compared to 92 patients managed from 1982 to 1990 (Group II). During the recent period, computed tomography (CT) scanning, endoscopic retrograde cholangiopancreatography (ERCP), selective visceral angiography, and percutaneous catheter drainage (PCD) techniques were available. The mean age of patients was similar in both groups (45 vs 44 years). Most pseudocysts in both periods represented complications of chronic pancreatitis due to alcohol abuse (82% vs 87%). Pancreatitis-associated complications occurring before management (fistula, obstruction, hemorrhage) were more frequent in Group II (19% vs 40%, P less than .05). There was a significant increase in the number of patients managed with external drainage in Group II (10% vs 52%) attributable to the use of PCD as definitive therapy in 46 per cent of patients in the recent period. Use of internal drainage procedures (cystgastrostomy, cystduodenostomy, cystjejunostomy) decreased in Group II (38% vs 16%, P less than .05). The use of lateral pancreaticojejunostomy (LPJ) combined either with caudal resection or cyst drainage has remained constant in both periods (32% vs 24%, NS). Patient morbidity was similar (26% vs 28%, NS) and mortality improved in Group II (9% vs 1%, P less than .05). Internal or external drainage for pseudocyst is often not definitive because of the underlying ductal disease. The authors' current approach is to manage large symptomatic cysts either with internal drainage or PCD; they employ octreotide acetate in the management of persistent pancreatic fistula following external drainage.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

The inhibition of monoamine oxidase by brofaromine.

The inhibition of rat liver mitochondrial monoamine oxidase-A (MAO-A) by brofaromine was time-dependent at low enzyme and inhibitor concentrations. The apparent sensitivity to inhibition decreased when the concentration of the mitochondrial preparation was increased. After preincubation of the enzyme with brofaromine repeated washing of the preparation, by sedimentation and resuspension, resulted in a gradual recovery of activity. This occurred more slowly than was the case when the reversible inhibitor amphetamine was used. After incubation with radioactively-labeled brofaromine the loss of radioactivity also occurred slowly. After incubation with radioactively-labeled pargyline polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphage (SDS-PAGE) showed the radioactivity to be associated with a peptide of approximate Mr 50,000, corresponding to the subunit of MAO. Pretreatment with unlabeled pargyline depressed this labeling by pargyline, indicating the latter compound to bind to the active-site of the enzyme. Labeling experiments with radioactive brofaromine indicated that there was a high degree of non-specific binding but that no significant radioactivity remained associated with the enzyme on SDS-PAGE. Chromatographic techniques and determination of H2O2 liberation indicated that, in liver there was no appreciable metabolism of brofaromine under the conditions used in the inhibition experiments. These data indicate brofaromine to be a tight-binding, but reversible inhibitor of MAO.

Animals↗
PubMed1991

Pancreatic pseudocysts. When to drain, when to wait.

Acute pain in the upper abdomen in a patient recovering from pancreatitis or abdominal trauma may herald a pancreatic pseudocyst. Although small cysts resolve spontaneously, those larger than 6 cm across usually require treatment to prevent such complications as rupture into adjacent structures and infection. The authors describe operative and nonoperative treatment methods and the success reported with each.

Drainage↗