Analysis of the morbidity, mortality, and cost of colostomy closure in traumatic compared with nontraumatic colorectal diseases

One hundred sixteen patients with acute colorectal diseases, operated upon emergently and needing an intestinal stoma, were reviewed to determine the cost and morbidity of treatment of patients with colorectal trauma compared to other surgical illnesses. The first group (57 patients) perforating colonic or rectal trauma, the second (30 patients) perforated colonic disease, the third (24 patients) nonperforated colonic disease, and the fourth (five patients) a colonic injury, unrecognized initially but requiring subsequent treatment with a stoma. For the initial operation, hospital stay, complications, mortality, and costs were less for patients in group 1 (colonic injury) than in groups 2 and 3 (inflammatory or neoplastic diseases). Colostomy closure, whatever the antecedent disease or injury, required an average ten-day hospitalization, had no mortality, a complication rate of 0 to 6 percent, and an average hospital cost of $6,500. The hospital stay and costs for the total treatment were slightly higher for nontraumatic illnesses, although the rate of colostomy closure was significantly less (68 and 77 percent versus 86 percent, P = .05).

A comparison of cefotaxime versus cefamandole in prophylaxis for surgical treatment of the biliary tract

Fiscal considerations prompted comparison of cefotaxime (a third generation cephalosporin) with cefamandole (a second generation cephalosporin) for prophylaxis in the surgical treatment of the biliary tract. One hundred and eight patients who underwent an operation upon the biliary tract received three 1 gram doses of cefotaxime (54 patients) or cefamandole (54 patients) at induction of anesthesia and then one and three hours later. The study was prospective, blinded and randomized. The groups (cefotaxime versus cefamandole) were statistically comparable for age, sex, diagnosis, type and duration of operation and positive cultures. The most prevalent bacteria isolated from qualitative aerobic and anaerobic cultures of bile and the wall of the gallbladder were Escherichia coli, Streptococcus and Klebsiella. The incidence of bactibilia in patients with one of these conditions was: 75 per cent for cancer; 69 per cent for patients more than 60 years old; 33 per cent for jaundice; 58 per cent for pancreatitis; 60 per cent for exploration of the common bile duct, and 22 per cent for acute cholecystitis. Microbiologic agar diffusion assays of tissue from the wall of the gallbladder, subcutaneous fat and rectus muscle and samples of bile and serum obtained 30 minutes after the second dose of antibiotic showed a statistically significant greater concentration of cefamandole in the wall of the gallbladder. Otherwise there was no difference between the concentration of cefamandole and cefotaxime. The groups showed no statistical difference for temperature of more than or equal to 38 degrees C. on two consecutive measurements, postoperative wound and urinary infections, postoperative hospital stay and days in the intensive care unit and incidence of readmission within a month. Prophylactic use of cefotaxime in a three dose regimen provided no advantage in prophylaxis compared with cefamandole.

Surgery in patients with acquired immunodeficiency syndrome

Between 1982 and 1985, 21 patients with acquired immunodeficiency syndrome (20 men and one woman; mean age, 36 years) underwent 31 surgical procedures at the Harbor/UCLA Medical Center, Torrance, or the UCLA Medical Center (skin, lymph node, and endoscopic biopsies were excluded). The operations included seven emergencies and 24 elective operations (eight major and 16 minor). Pathologic findings included cytomegalovirus colon perforation (two), disseminated Kaposi's sarcoma (KS) of the small and large bowel (one), cystic duct obstruction by KS (one), poorly differentiated gastrointestinal lymphoma (one), Candida acalculous cholecystitis (one), central nervous system toxoplasmosis (two), amebic encephalitis with abscess (one), staphylococcal botryomycosis of the pericardium (one), pulmonary KS (one), and cytomegalovirus (one). The overall operative (30 days) mortality rate was 48% (10/21). The emergency surgery rate was 57% (4/7), elective, 43% (6/14). The high operative mortality rate in these patients was usually due to progression of opportunistic infections or malignancy.

Measuring S100 protein and neurone specific enolase in melanocytic tumours using video image analysis

Using a computed video image analysis system, the staining intensity for both neurone specific enolase (NSE) and S100 protein was measured in sections from 19 malignant melanomas and 16 benign melanocytic lesions. The results of this study confirm previous reports that NSE and S100 protein are useful markers for malignant melanoma. NSE staining intensity in the cases of malignant melanoma was significantly higher than that in benign naevi (p = 0.011). Intensity of staining for S100 protein was not significantly higher in the malignant melanomas. There was, however, a significant S100 gradient when comparing superficial and deep intradermal portions of these tumours (p = 0.003). This feature was not seen in benign naevi. The greatest intensity of S100 protein staining was found in the deeper portions of the malignant melanomas. This gradient difference was not seen with staining for NSE. Although it seems that the overall intensity of staining for NSE is more effective in differentiating between benign and malignant lesions, the difference in staining intensity between the superficial and deep portions of the tumour may be the better indicator of adverse behaviour in lesions in which the diagnosis of malignancy is uncertain.

Early computerized tomography as a predictor of outcome in acute pancreatitis

Fifty-one patients with the clinical diagnosis of acute pancreatitis were studied prospectively with early computerized tomography. It was found to be superior to ultrasonography for detecting acute pancreatitis and defining its extent. Grading of the initial computerized tomographic findings according to the extent of pancreatic inflammatory reaction identified patients with a high risk of local complications after onset of acute pancreatitis. Extension of the pancreatic inflammatory reaction into one or more peripancreatic areas with the simultaneous finding of pancreatic or extrapancreatic fluid collection or both was associated with a high frequency of pancreatic complications requiring surgical intervention and death. We believe that the severity of pancreatitis as shown by initial computerized tomographic scan is a more accurate predictor of clinical outcome than Ranson's criteria.

Purification of the fructose 1,6-bisphosphate-dependent lactate dehydrogenase from Streptococcus uberis and an investigation of its existence in different forms

The fructose 1,6-bisphosphate [Fru(1,6)P2]-dependent lactate dehydrogenase in cells of Streptococcus uberis N.C.D.O. 2039 was purified by a procedure that included chromatography on DEAE-cellulose and Blue Sepharose CL-6B in phosphate buffers. The enzyme appeared to interact with Blue Sepharose through NADH-binding sites. The homogeneous enzyme had catalytic properties that were generally similar to those of other Fru(1,6)P2-dependent lactate dehydrogenases, and it had no catalytic activity in the absence of Fru(1,6)P2. Its existence in different forms, depending on conditions, was investigated by ultracentrifugation, analytical gel filtration and activity measurements. It consisted of subunits with Mr 35,900 +/- 500 and, in the presence of adequate concentrations of Fru(1,6)P2, phosphate or NADH, it existed as a tetramer, whereas when these ligands were in lower concentrations or absent, the subunits were in a concentration-dependent association-dissociation equilibrium. Dissociation occurred slowly and inactivated the enzyme, and although added ligands reversed the dissociation, the lost activity was at best only partly restored. An exception occurred when dissociation was caused by a decrease in temperature, in which case the lost activity was fully restored at the original temperature. The tetramer also lost activity at certain ligand concentrations without dissociating. The results together indicated the presence on the enzyme of two classes of binding site for both Fru(1,6)P2 and NADH, and the likelihood that phosphate bound at the same sites as Fru(1,6)P2. Two different ligands together were much more effective at preventing inactivation and dissociation than was expected from their effectiveness when present separately. It was concluded that tetrameric forms of the enzyme rather than the enzyme in association-dissociation equilibrium were involved in the regulation of its activity in vivo.

Biliary disease in pregnancy: strategy for surgical management

Acute biliary tract disease complicated intrauterine pregnancy in 26 patients seen during a 5 year period. Biliary symptoms were distinct and occurred during the first trimester in 7 patients, the second trimester in 5 patients, the third trimester in 12 patients, and in two early postpartum patients. Nine patients had marked hyperamylasemia which resolved with medical management, and no severe cases of pancreatitis occurred. Ultrasonography was used to confirm the presence of gallstones in 18 patients and demonstrated dilated intrahepatic ducts in one of two patients with surgically proved choledocholithiasis. Nineteen patients had cholecystectomy and cholangiography, and 4 had common bile duct explorations. Only two of seven patients who presented in the first trimester had term pregnancy. Diagnosis of cholelithiasis in pregnancy by ultrasonography is accurate and reliable. The risk to the fetus of radionuclide scanning and conventional radiography is not justified. Secondary hyperamylasemia is common but responds to conservative therapy. Operation may be delayed until delivery in most patients, with urgent exploration reserved for uncertainty in diagnosis, choledocholithiasis, or acute cholecystitis that does not resolve with medical measures.

Non-carcinoid epithelial tumours of the appendix--a proposed classification

Examination of 33 cases of non-carcinoid epithelial tumours of the appendix and a review of the previous literature has led us to propose a new classification of these lesions. It is based on nomenclature currently used for similar mucosal proliferations in the colon, facilitating communication between pathologists and clinicians with respect to their nature and possible behaviour. The use of the term "mucocele" to describe any lesion in which there is mucinous distension of the appendiceal lumen, irrespective of the type of underlying mucosal pathology, is now largely discredited. Yet, although a resemblance of some appendiceal lesions to similar lesions in the colon has been recognized, current terminology is still confused by the use of "cystadenoma". We have been able to place all of the known non-carcinoid appendiceal mucosal tumours into 4 main diagnostic categories, these being--adenoma, hyperplasia, mixed adenoma/hyperplasia and adenocarcinoma, and propose these terms as the basis for a new classification.

Areas of spatial interaction for a hyperacuity stimulus

We report that the ability to detect a small vernier offset (less than 5 sec of arc in many individuals) between two small spots of light separated by a narrow gap can be disrupted by presenting additional targets in close proximity to the vernier stimulus. A rectangular background of light, centered on the vernier stimulus, elevates offset threshold by a factor of two when the total width of the background is 3-4 min arc. Backgrounds narrower or wider than 3-4 min have less or no effect on vernier threshold. These areas of spatial interaction extend to either side of a vertically-oriented vernier stimulus, or above and below a horizontally-oriented stimulus, and their extent is dependent upon the gap size of the two-dot stimulus. The effect of the presence of the background on vernier threshold cannot be accounted for by spatial interval cues nor by changes in the visibility of the stimulus. Two alternative interpretations of the results are presented to develop a description of the underlying mechanisms which produce hyperacuity spatial interactions.

Comparative sensitivity of bovine and rodent acetylcholinesterase to in vitro inhibition by organophosphate insecticides

Biochemical studies were conducted to compare the in vitro sensitivities of bovine and rodent brain and erythrocyte cholinesterases to inhibition by Dyfonate-oxon, paraoxon, and malaoxon. This comparison was done to determine if the reported greater sensitivity of cattle to Dyfonate might be explained by a greater sensitivity of the target enzyme, acetylcholinesterase, in cattle to inhibition by Dyfonate's toxic metabolite, Dyfonate-oxon. Studies were conducted with brain homogenates and lysed erythrocytes obtained from cows and from male and female rats. Additional studies were conducted with a commercially available sample of purified bovine erythrocyte acetylcholinesterase (ACHE). In all cases, the concentrations of organophosphates required to produce 50% inhibition (IC50) of enzyme activity were determined. Cow brain ACHE was 1.7 to 3.8 times more resistant to inhibition by Dyfonate-oxon, paraoxon, and malaoxon than was brain ACHE from male or female rats. For both species, paraoxon was 1.2 to 1.6 times more potent than Dyfonate-oxon and 3.8 to 6.9 times more potent than malaoxon. The bimolecular reaction rate constants (ki) were also determined for inhibition of brain ACHE of cows and male rats by the three organophosphates. In general, the ki data were in agreement with the IC50 data indicating that cow brain ACHE was less sensitive than rat brain ACHE to inhibition. Additional IC50 studies were conducted with lysed erythrocytes from cows and from male and female rats. Both quantitative and qualitative differences between species and among the organophosphates were in excellent agreement with the results of the brain ACHE studies. Also, in related studies with purified bovine erythrocyte ACHE, there was excellent agreement with the results of tests involving ACHE inhibition in erythrocyte lysates. This study demonstrated that, as an inhibitor of ACHE in vitro, Dyfonate-oxon was equal to or slightly lower in potency than paraoxon and more potent than malaoxon. In addition, the study demonstrated that, in general, ACHE from brain or erythrocytes of cows was less sensitive to in vitro inhibition by organophosphates than was that from male or female rats. Thus, the apparent greater susceptibility of cows to Dyfonate, in vivo, cannot be explained on the basis of an unusual target enzyme (ACHE) sensitivity to inhibition by Dyfonate-oxon.

Functional visual effects of lesions located near the optic nerve head

Three patients with retinal lesions near or impinging on the optic nerve head are presented. Three different functional disruptions are demonstrated by quantitative layer-by-layer perimetry. In one, a patient who primarily exhibited subretinal neovascularization, inner retinal functions were anomalous; but the overlying nerve fiber bundle was as yet not affected. In the second patient, an individual with possible histoplasmosis causing an outer retinal/choroidal lesion, the overlying nerve fiber bundle was affected causing apparent retrograde changes in inner retinal function at remote visual field locations; but another aspect of optic nerve function (time-dependent response) was not anomalous. These apparently retrograde changes were essentially identical to functional changes previously demonstrated in patients with established open-angle glaucoma. In the third patient, with presumed toxoplasmosis, there were clear-out time-dependent anomalous responses consistent with optic nerve involvement, as previously reported in patients with optic neuritis. There were also modest, time-stable, nerve fiber bundle defects present in this third patient. Together, these results demonstrate that lesions in the area of the disc can have very different functional consequences, and that quantitative psychophysical techniques can elucidate these differences.

Radiological findings in seropositive juvenile chronic arthritis (juvenile rheumatoid arthritis) with particular reference to progression

The radiological effects of peripheral joint disease in 81 patients with seropositive juvenile chronic arthritis were studied retrospectively with an average length of follow up of 11 years. The patients comprised 63 girls and 18 boys with average ages of onset being 10.7 years and 12.1 years respectively. All had developed positive serology within the first year of the disease. X-rays available in 70 of these patients at five years from onset of the disease showed erosive change to be present in all but three. The sites most commonly affected included the carpus, the metacarpal, the metatarsal, and interphalangeal joints, though a third of the patients also showed erosive change in large joints such as hips, knees, or shoulders. Between five and 10 years after disease onset progression of x-ray changes was evident in most patients, with additional joints becoming involved in about one third, though the distribution of joints was similar. After 15 years or more of disease the radiological changes tended to be more stable, but various mechanical difficulties often secondary to poor growth and degenerative change and to primary destructive inflammatory arthritis were evident. No specific drug regimen was found to have been universally effective in suppressing disease, and the frequency of side effects was a significant factor in preventing treatment schedules being maintained for long enough to be effective.

Epithelial lining methods in esophageal repair: a comparative study using pedicle flaps in cats

Methods of restoring luminal lining in repair of partial-circumferential esophageal defects were evaluated to compare incidences of strictures and fistulas and quality of surface lining. In cats 50% and 67% circumferential esophageal defects were repaired by direct closure or pedicle flaps (latissimus dorsi) that were unlined (lining restored by epithelialization from wound margins) or that carried lining of normal skin (myocutaneous flaps), skin grafts, or mucosal grafts. Repairs were evaluated for esophagocutaneous fistulas, luminal stricture, flap luminal surface area, and quality of epithelial surface 6 weeks after surgery. Direct closure of 50% circumferential defects was as satisfactory as any flap repair method. Direct closure of 67% circumferential defects caused high incidences of fistulas and strictures, which were lessened by flap reconstructions. Among flap lining methods, normal skin (myocutaneous flaps) gave the lowest incidence of fistulas and strictures and the highest surface quality, but a high incidence of skin paddle loss occurred in this model. Split-thickness epithelial grafts were nearly as satisfactory as myocutaneous flaps, and less lining loss occurred. Epithelialization of unlined flaps gave the poorest results since lining was thin and often incomplete, and wound contraction produced loss of surface area and strictures. The findings are discussed from a perspective of wound healing physiology, and implications for clinical application are presented.

Cancer of the distal esophagus and cardia: preoperative irradiation prolongs survival

Ninety-five patients with carcinoma of the esophagus and gastric cardia seen between 1979 and 1984 were managed in one of four ways: radiotherapy alone (6,000 rads), esophagogastrectomy alone, preoperative radiotherapy (4,000 rads over 4 weeks) followed by esophagogastrectomy, or no definitive treatment for patients with advanced disease. Patients who receive radiotherapy alone or no definitive therapy were considered unfit for operation; however, those patients who had operation only were equivalent with regard to histologic stage and risk to patients who received preoperative radiotherapy and surgery. Patients who received no definitive therapy died within 1 year, with a mean survival of 3.7 months. The mean survival for patients who received radiotherapy only was 8.3 months; for those who had surgery alone, 13 months; and for those who had preoperative radiotherapy, 24 months. Patients who received preoperative radiotherapy had significantly longer survival times when followed 12, 15, and 18 months postoperatively. Preoperative radiotherapy did not improve overall resectability, and postoperative mortality was similar in the two surgical groups. In comparable patients treated by esophagogastrectomy, preoperative irradiation prolonged the disease-free survival time and is advocated for all surgical candidates.

A randomized, prospective study of perioperative antimicrobial prophylaxis for vascular access surgery

A blinded, randomized, prospective study of 38 chronic renal failure patients was done to evaluate perioperative antibiotics in the prevention of postoperative infection of vascular access prostheses. Expanded polytetrafluoroethylene (PTFE) hemodialysis grafts were placed either in radiocephalic (19) or femorosaphenous (19) position. Cefamandole or placebo was given intravenously 30 minutes prior to operation and six to 12 hours postoperatively. The overall infection rate for the group was 26.3 percent with two of 19 antibiotic-treated and eight of 19 placebo-treated patients developing an infection (p less than 0.04). Grafts placed in the thigh have a greater risk of intraoperative contamination and infection. Postoperative infection associated with implantation of hemodialysis prostheses was significantly reduced by perioperative antimicrobials.

Retinal damage in pigmented and albino rats exposed to low levels of cyclic light following a single mydriatic treatment

The present study demonstrated that less than three days of exposure to low levels of normally cycled ambient illumination are sufficient to cause death to photoreceptor cells in adult pigmented and albino rat. Cyclic light levels as low as 133 and 320 lux were found to destroy photoreceptor cells. A single mydriatic treatment with atropine immediately preceding the three-day exposure was sufficient to permit the effect in pigmented rats. No mydriasis was required for albino rats. When pigmented rats were reared in either 3 lux or 100 lux, it was found that these different light histories did not significantly affect the rats' subsequent susceptibility, during mydriasis, to retinal damage by cyclic illumination.

Flicker detection in the albino rat following light-induced retinal damage

The effect of light-induced retinal damage on the behaving rat's critical flicker-fusion frequency (CFF) was studied by determining the CFF at scotopic and photopic luminances both before and after exposure to damaging light. The CFF was reduced but not abolished following damaging light exposure. The shapes of the functions relating CFF to luminance before and after exposure suggested that scotopic visual function may have survived the light damage better than did photopic function. Anatomical and biochemical measures of retinal damage indicated that 91-93% of the outer nuclear layer (ONL) and 99% of the rodopsin had been lost.

The effects of variations in percent of naturally occurring complex and simple carbohydrates on plasma glucose and insulin response in individuals with non-insulin-dependent diabetes mellitus

In the present study, 12 patients with non-insulin-dependent diabetes mellitus (NIDDM) consumed eucaloric, mixed food diets on three consecutive days. Diets provided 50% of the calories as carbohydrate, 35% as fat, and 15% as protein. The percent of carbohydrate fed as complex (starches) and simple (mono- and disaccharides) varied among the 3 days. On day 1, the diet contained 80% of the carbohydrate as complex and 20% as simple (80/20); another contained 50% complex and 50% simple (50/50); and the final diet contained 20% of the carbohydrate as complex and 80% as simple (20/80). All simple carbohydrates represent naturally occurring sugars in fruits, vegetables, and dairy products. No refined sugars were added to any of the diets. The three experimental diets were randomly assigned using a 3 X 3 Latin square design. Blood was obtained hourly from 0800 to 1700 h for day-long glucose and insulin concentrations, and 24-h urine collections were made for the measurement of urine glucose. Mean (+/- SEM) day-long glucose concentrations were significantly greater for the 80/20 diet (2245 +/- 199 mg/dl X h, P less than 0.05) than for either the 50/50 (2030 +/- 157 mg/dl X h) or the 20/80 diets (2008 +/- 160 mg/dl X h). No significant differences were noted between the 50/50 and the 20/80 diets. In contrast, day-long insulin concentrations were not significantly different with 401 +/- 62, 370 +/- 50, and 369 +/- 60 mu U/ml X h on the 80/20, 50/50, and 20/80 diets, respectively. Twenty-four-hour urinary glucose excretion paralleled plasma glucose concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of iron deficiency on respiration of hamster cheek-pouch epithelium in vitro

Iron-deficiency anaemia was induced in hamsters by feeding a low-iron diet coupled with weekly bleeding. Respiration, assessed by measuring oxygen uptake, was significantly reduced (p less than 0.002) in cheek-pouch epithelia from iron-deficient animals. To relate data on oxygen consumption to cell numbers, the cell densities of the basal and maturation compartments were measured. The cell density of the maturation compartment in iron-deficient animals was significantly reduced (p less than 0.05), whereas that of the basal cell compartment was marginally higher than in control animals. However, the cell density of the tissue as a whole was similar in both groups. Thus, the reduced oxygen consumption in iron deficiency was not due to a reduction in cell numbers. Although there was a significant reduction in epithelial volume in the iron-deficient group, this was not sufficient to account for the reduced oxygen uptake in cheek-pouch epithelia from these animals. It is concluded that iron-deficiency anaemia affects cell respiration directly, probably by interfering with the amounts and/or functions of iron-containing enzymes or cytochromes in the electron-transport chain.

Effect of arteriovenous fistula on wound healing and skin blood flow

In dogs, the tension in a surgical incision and a measure of subcutaneous blood flow were obtained adjacent and distal to a groin arteriovenous (A-V) fistula. At 7 days, in the fistula-bearing leg compared with the control there was an increased force required to separate the wound edges adjacent to the fistula, while the opposite was true for the distal incision. Radioxenon washout, used for a measure of subcutaneous blood flow, was more rapid distally in the control leg. In the fistula leg this relationship was reversed. These studies indicate there is a redistribution of blood in the leg when an A-V fistula is constructed, with augmented subcutaneous flow and increased wound strength adjacent to the fistula and the converse at a distal site in the limb.

Sclerosant treatment of varicose veins and deep vein thrombosis

Impedance plethysmography (IPG) and the Doppler ultrasonographic probe were used to assess whether thrombophlebitis, initiated by injection of a sclerosant into superficial varicose veins, extended to involve the deep veins of the leg. Sixty-seven legs were treated with compression sclerotherapy in 50 patients (26 men, 24 women) whose mean age was 53 years. Indications for this therapy were unacceptable appearance (n = 37), pain (n = 13), cramps (n = 11), and stasis ulcer (n = 6). Each leg received an average of six injections (range, three to 11) of 0.5 mL of sodium tetradecyl sulfate. Blood flow in the deep veins was studied immediately before injection of the sclerosant and one week and two weeks afterward. In each leg, no change in either of these studies was found at one and two weeks following injection treatment. In nine extremities, delayed venous emptying was found on IPG. This persisted after sclerosis and was interpreted as evidence of a previous deep vein thrombosis.

Effect of source of dietary carbohydrate on plasma glucose, insulin, and gastric inhibitory polypeptide responses to test meals in subjects with noninsulin-dependent diabetes mellitus

Previous reports have documented the fact that plasma glucose and insulin responses can vary in response to the ingestion of different carbohydrate-rich foods. This has led to the creation of a "glycemic index," a classification of dietary carbohydrates on the basis of the relative rise in plasma glucose after the administration of the food in question as compared to a standard glucose challenge. In order to test the clinical utility of these observations, we evaluated plasma glucose, insulin, and gastric inhibitory polypeptide responses to four major sources of carbohydrate (potato, rice, spaghetti, lentil) as part of a conventional mixed meal in patients with noninsulin-dependent diabetes mellitus. Each test meal provided 40% of the subjects' calculated caloric requirement and contained 15% of total calories as protein, 40% as fat, and 45% as carbohydrate. The test carbohydrate represented 66% of total carbohydrate. The results indicated that plasma glucose concentrations after meals containing equal amounts of carbohydrate as rice, spaghetti, or lentil were similar and somewhat lower than meals containing potato. The plasma insulin responses to the four carbohydrate foods paralleled the glucose responses. Changes in gastric inhibitory polypeptide levels did not account for the effect of potato. These results are totally disparate from what would have been predicted by previously published values for the "glycemic index" of the four foods studied, and suggest that a "glycemic index" based on isolated challenges would have minimal clinical utility in efforts aimed at reducing postprandial hyperglycemia in patients with noninsulin-dependent diabetes mellitus.

Retinal boundaries and visual function in gyrate atrophy

Three patients with gyrate atrophy of the retina and choroid underwent fundus photoperimetry, the combination of fundus photography and visual field analysis within the same instrument, to examine the correspondence between the funduscopically observed, scalloped margin of remaining retina and the functional limit of the peripheral visual field. The results suggest that near the border between remaining retina and atrophic areas, visual sensitivity falls off quite rapidly, producing perimetric isopters that conform closely to the scalloped retinal margin. In some instances, visual function can be demonstrated in islands of remaining retina that are totally surrounded by atrophic areas. This study demonstrates the usefulness of fundus photoperimetry in following the course of degenerative retinal diseases.

The effects of image degradation by cataract on vernier acuity

The resistance of certain types of hyperacuity tasks (eg, vernier acuity) to optical degradation of the retinal image has been demonstrated previously. This suggests that such a task might provide a means of filling the clinical need for a reliable test of retinal function in the presence of cataracts and other ocular opacities. In the present study, we measure several aspects of vernier acuity performance in cataract patients. These data provide an early basis for the development of a vernier acuity test to detect retinal/neural visual loss prior to cataract surgery. We report the results of measurements in 15 cataract patients using a two-dot vernier acuity task with variable separation between the two dots (gap). The data indicate that the shape and mean level of the vernier threshold-versus-gap function co-vary with the functional severity of the opacity as corroborated by Snellen acuity measures. Furthermore, the optical effects of the cataracts we studied are very similar to the effects of degrading the visual stimulus by interposing ground glass for a normal observer. We conclude that the shape of the vernier threshold-versus-gap function is a good indicator of the functional severity of the cataract in patients with otherwise normal vision.

Relating vernier acuity and Snellen acuity in specific clinical populations

The relationship between vernier acuity and Snellen acuity in a group of cataract patients was examined. The vernier stimulus consisted of two small spots of light, vertically separated by a variable-sized gap. The Snellen stimulus was a standard projected Snellen chart. The form of the relation between vernier and Snellen acuity was found to depend upon the vernier gap size used. Specifically, when the smaller gaps of 4 or 8 min of arc are used, the two types of acuity are linearly related. When the gap is 16 or 32 min of arc, (or if best vernier performance irrespective of gap is considered) vernier acuity is related to Snellen acuity by a power function with an exponent less than one, within this clinical population. Thus, with increasing degrees of retinal image degradation caused by cataract, optimum vernier acuity is impaired at a slower rate than Snellen acuity. Our results in cataract patients are compared to results obtained by others within a population of strabismic and anisometropic amblyopes.

Hyperacuity perimetry. Assessment of macular function through ocular opacities

"Hyperacuity perimetry" provides localized measures of visual performance across the central visual field that are resistant to the retinal image degradation caused by media opacities. A normal observer, viewing a vernier stimulus through an artificial opacity (ground glass), exhibits a pronounced performance improvement with foveal viewing, relative to viewing at visual field points just 2 degrees to 4 degrees parafoveal. Patients with central lesions exhibit anomalous hyperacuity perimetric profiles, even in the presence of a simulated ocular opacity. We conclude that in patients with media opacities, hyperacuity perimetry can preoperatively evaluate the distribution and size of areas of visual loss across the central visual field and the stability and location of primary fixation. This potentially powerful test of macular function behind media opacities is as easy to apply as any static visual field measurement.

The acid end-products of glucose metabolism of oral and other haemophili

The acids produced in broth culture by various species of oral haemophili and by stock strains of capsulated and other haemophili were identified and measured by gas-liquid chromatography. Succinic acid was the major acid end-product of all strains, with acetic acid also being regularly produced but in smaller amounts. A stock strain, Haemophilus parainfluenzae NCTC 4101, produced less succinic acid than other strains of haemophili. Strain NCTC 4101 possessed all the enzymes of the tricarboxylic acid cycle, as previously reported, but in the other haemophili examined only succinic dehydrogenase, fumarase and malate dehydrogenase could be detected. No other enzymes of the tricarboxylic acid cycle were detected and isocitrate lyase, malate synthase and pyruvate carboxylase were also absent. Phosphoenolpyruvate-carboxylase was present in all strains. A partial tricarboxylic acid cycle and marked malate dehydrogenase activity appear to be characteristic of haemophili. The pathway to succinate in haemophili appears to be via carboxylation of phosphoenolpyruvate to oxalacetate and thence via malate and fumarate. The results of tracer studies on a single oral strain of H. parainfluenzae using various labelled substrates were in keeping with this proposed metabolic pathway.

Maternal isoimmunisation resulting in combined immunodeficiency and fatal graft-versus-host disease in an infant

Isoimmunisation to platelet and lymphocyte antigens occurred during a woman's seven pregnancies and resulted in congenital thrombocytopenia and lymphocytopenia in the last two offspring. The youngest baby died aged 16 days of severe combined immunodeficiency (SCID) with maternal graft-versus-host disease. The other affected child, however, recovered fully from thrombocytopenia and lymphocytopenia after exchange transfusion for presumed sepsis. The clinical courses indicated that an isoimmune process had caused both the thrombocytopenia and the lymphocytopenia. In accord with this conclusion, maternal titres of IgG antibodies against paternal platelets fell continuously in serial blood samples taken after the last pregnancy. Cytotoxicity studies of the maternal serum towards lymphocytes from the other siblings and from unrelated donors showed that the paternal antigen involved was a non-HLA determinant. It is postulated that isoimmune lymphocytopenia with subsequent immunological suppression is a potential mechanism for SCID and intrauterine engraftment of maternal lymphocytes.

Management of adenocarcinoma extending to the middle and upper part of the esophagus

Of 30 patients with adenocarcinoma of the gastroesophageal junction treated between 1977 and 1982, 11 had tumor spread to the middle or upper thirds of the esophagus. Ten were treated with esophagogastrectomy by the Lewis approach, with two operative deaths. All of the tumors had spread to the periesophageal tissues. The eight surviving patients had relief of dysphagia. Five died with recurrent tumor after a mean survival time of 11 months; three are alive at five and 16 months (without evidence of disease) and 13 months (with recurrence). Adjuvant preoperative radiation therapy was used in four patients, three of whom received concomitant total parenteral nutrition. Despite the poor prognosis of this particularly unfavorable subset of patients with tumors of the gastroesophageal junction, operative resection provides acceptable palliation. Further study of adjuvant modalities is needed.

CT guided paravertebral biopsy of the mediastinum

A simple technique for computed tomographic guided biopsy of esophageal and periesophageal lesions is described. The method utilizes an extrapleural, paravertebral route that allows access to the periesophageal area without entering the lung or pleural cavity.

Actinomyces denticolens Dent & Williams sp. nov: a new species from the dental plaque of cattle

Six strains of actinomyces isolated from the dental plaque of cattle were assigned presumptively to the genus Actinomyces on the basis of Gram reaction, cellular and colony morphology and acid end-products of metabolism. This assignment was confirmed by the peptidoglycan composition which is shared with Actinomyces species from dental plaque. These cattle strains formed a homogeneous group on the basis of cell wall carbohydrate components, DNA base composition, polypeptide molecular weight distribution and physiological reactions but could not be classified with any recognised species of Actinomyces. A new taxon Actinomyces denticolens is proposed for these strains.

The resistance of selected hyperacuity configurations to retinal image degradation

Traditional visual acuity is based on resolution of stimulus features, whereas hyperacuity (ie, vernier acuity) is based on relative localization of stimulus features. Since resolution acuity is influenced severely by optical degradation, it is often not a suitable measure of the status of the retinal/neural visual system in conditions of optical degradation. In the present study, the authors investigate the effect of optical degradation on various relative localization tasks. Thresholds for three types of hyperacuity stimuli (line vernier, two-dot vernier, and line tilt) were measured under various degrees of image degradation, produced by viewing the targets through ground glass. The results indicate that when a hyperacuity stimulus is optically degraded, relative localization threshold increases only slightly for certain separations of the comparison features. In comparison with resolution acuity, hyperacuity threshold at the optimum feature separation is quite resistant to image degradation. This finding demonstrates a potential for the clinical application of hyperacuity as a test of visual function in the presence of cataracts and other media opacities.

The role of gastrointestinal microflora in the pathogenesis of complications of mesenteric ischemia

Mesenteric ischemia is a catastrophic event, which has a mortality due to florid sepsis that approaches 100%. The demography of the bacterial changes has not been documented. After 72 hr of colonic ischemia in the dog, the total number of anaerobic organisms increased while the number of aerobic organisms decreased. After 24 hr of ischemia, anaerobic bacteria appeared only in the portal vein and persisted. Cultures of peritoneal fluid and aortic blood became positive for the same anaerobic organisms after 48 hr. Acute colonic ischemia promotes a relative overgrowth of intraluminal anaerobic bacteria, which progressively invade the portal vein and later the systemic circulation.

Early portal anaerobic bacteremia in mesenteric ischemia

The progressive changes in colonic flora and the pattern of bacterial invasion of extracolonic sites were studied in a canine ischemic colon preparation. After 72 hours of colonic ischemia produced by ligation of the common colic and caudal mesenteric arteries, the total number of anaerobic organisms increased, with a concomitant decrease in aerobic organisms within the colon lumen. After 24 hours of ischemia, anaerobic bacteria only appeared in the portal vein and persisted. Aortic blood and peritoneal fluid cultures became positive after 48 hours with the same organisms. Polymicrobial intra-abdominal abscess and systemic Escherichia coli bacteremia occurred only in one animal with necrotic colonic disruption. Acute colonic ischemia promotes an overgrowth of intraluminal anaerobic bacteria, which penetrate the mucosal barrier and progressively invade the portal vein and, later, the systemic circulation.

Comparison of infectibility of vascular prosthetic materials by quantitation of median infective dose

The current technique for investigating the response of vascular prosthetic material to infection is by challenge with a sublethal dose of bacteria, usually an intravenous infusion of 10(8) organisms in an animal model. This large bacterial inoculum, however, obscures any difference in the infectibility of prostheses that may be inherent in the material, its incorporation into host tissues, or its modification by antibiotic impregnation, all of which are clinically important in resistance to infection. We have developed a sensitive method for determination of the susceptibility to infection of vascular prostheses based on calculation of the number of bacteria required to infect a specific prosthesis in 50% of trials (ID50). Following implantation of the prosthesis to be tested in the canine infrarenal aorta, a dose-response curve was calculated by the intravenous infusion of known inocula of S. aureus (at log intervals from 10(2) to 10(8) bacteria). At 6 weeks, the prosthesis was harvested and cultured to document infection with S. aureus. A characteristic sigmoid curve Kesulted, from which the ID50 was determined. To test this method, a comparison was made between commercial human umbilical vein graft (HUVG), HUVG impregnated with silver sulfadiazine, and double-velour Dacron in 60 dogs. Although all prostheses were infected by the standard 10(8) inoculum, an approximately tenfold increase in the resistance to infection between treated and untreated HUVG (less than 10(2) to 10(2.8) and a fourfold increase in resistance between treated HUVG and double-velour Dacron (10(2.8) to 10(3.2] was demonstrated in the dose-response curves. Since the number of bacteria in postimplant bacteremia rarely exceeds 10(2) organisms/ml, such differences in infectibility can be clinically significant. ID50 determination provides a sensitive, reproducibleble method for quantitating resistance to infection in vascular prostheses.

Retinal image noise and vernier acuity

The effects of optically produced "noise" in the retinal luminance distribution of a vernier stimulus are demonstrated in two experiments. In the first, vernier performance with a bright, two-dot target is shown to improve upon the introduction of a luminous background field, relative to performance with a completely dark background. The brighter background probably acts as an adapting field, reducing the visibility of the retinal image "noise". The second experiment demonstrates that, under defocused conditions, introduction of a low-pass spatial filter that removes phase-reversed high spatial frequency components can enhance vernier performance. Thus, high spatial frequency information may interfere with the vernier response when phase information is disturbed by defocus.

Surgical management of unilateral groin infection after aortofemoral bypass

The most common site for infection in reconstructive peripheral vascular operations is the inguinal area. Treatment is controversial, with recommendations ranging from antiseptic irrigation techniques to total graft excision. We present a plan for the surgical management of unilateral groin infection after aortofemoral bypass that was used in five patients. After assuring the viability of the extremity independent of the prosthesis, by compression of the graft limb with a concurrent Doppler ankle to wrist ratio index exceeding 0.3, vascular repair was performed as a two-stage procedure combining clean retroperitoneal detachment of the infected graft limb and inguinal excision of the involved graft limb followed by delayed vascular reconstruction by extra-anatomic cross femoral bypass. This has shown to be a reliable surgical method for salvaging the aortofemoral bypass with unilateral groin infection.

Bilateral versus unilateral electroconvulsive therapy: efficacy in melancholia

The authors compared the therapeutic efficacy of bilateral and unilateral electroconvulsive therapy (ECT) in 51 patients with endogenous depression who were randomly assigned to bilateral (N = 24) or unilateral (N = 27) ECT. Seizures were monitored by oscilloscope. After 6 treatments blind assessment on a modified Hamilton depression scale showed an 81.1% improvement in the bilateral group compared with a 55.5% improvement in the unilateral group. Additional treatments were prescribed ad libitum by a hospital psychiatrist who was unaware of each patient's electrode placement. The unilateral group received more total treatments and were more frequently switched to bilateral ECT. These results were independent of age, severity of illness, or sedative drug administration.

Effects of defocus on monkey (Macaca nemestrina) contrast sensitivity: behavioral measurements and predictions

An observer's contrast sensitivity function (CSF) can be affected by degradation of either the optical or neural components of the visual system. In a continuing effort in this laboratory to separate these two components in infant and mature monkeys, we have measured behavioral CSF's with the retinal image defocused by as much as 6 D. With increased defocus, sensitivity decreases much more rapidly at high spatial frequencies than at low frequencies. Furthermore, we find that calculations of retinal image contrast, based upon available optical parameters of the monkey eye, underestimate the amount of optical defocus which still allows pattern detection by our monkeys at high spatial frequencies. Several possible explanations for this apparent conflict are discussed, including optical aberrations present in the primate eye, and the "spurious resolution" of defocused sinusoidal gratings.

Dehydrogenase patterns in the taxonomy of Bacteroides

The malate dehydrogenase (MDH) electrophoretic mobilities of 128 strains of bacteroides belonging to 17 species, including three subspecies of Bacteroides melaninogenicus and two subspecies of Bacteroides ruminicola, were examined. Amongst the pigmented bacteroides, the migration of this enzyme correlated well with recognized taxa, and only one strain, VPI 9085 was clearly different. Other species such as B. oralis, B. buccalis, B. denticola, B. pentosaceus, B. bivius, B. disiens and B. ruminicola were delineated by the combined use of MDH and glutamate dehydrogenase. Forty-three strains belonging to the 'B. fragilis group' differed from the above species in possessing glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, and reference strains as well as fresh isolates were assigned to the correct species by the mobility pattern of these two enzymes. Other properties of MDH such as the pH optima for the oxidation of malate or the reduction of oxaloacetate were of limited taxonomic value. However, the alkaline stability of this enzyme at pH 9, 10 and 11 clearly differentiates the saccharolytic from the non-saccharolytic species of pigmented bacteroides with the latter showing highly stable enzymes with a half life greater than 50 min.