Long- or short-limb gastric bypass?

The aim of this study was to determine whether longer limb length improved results of gastric bypass in patients who were morbidly obese (body mass index <50 kg/m(2)) or superobese (body mass index >50 kg/m(2). A total of 242 patients were followed for a mean of 5.5 years. The standard operation was a Roux-en-Y gastric bypass with a 40 cm Roux limb and a 10 cm afferent limb. The long-limb operation had a 100 cm Roux limb and a 100 cm afferent limb. Morbidly obese patients did not benefit from a long-limb bypass. The final body mass index was 28.6 +/- 4.7 kg/m(2) in the short-limb group and 28.5 +/- 3.8 kg/m(2) in the long-limb group. The superobese patients did benefit from a long-limb bypass. Final body mass index was 35.8 +/- 6.7 kg/m(2) in the short-limb patients and 32.7 +/- 5.1 in the long-limb patients (P = 0.049). A subgroup of 20 patients, all of whom had a body mass index greater than 60 kg/m(2), benefited the most from long-limb bypass. No macronutritional side effects unique to the long-limb bypass were encountered.

The hinged back plate mechanism in glassy wax tests of New Zealand male soft scale insects (Hemiptera: Coccoidea: Coccidae).

Male scale insects (Hemiptera: Coccoidea) undergo a metamorphosis of the neometabola type, from scale-like nymph through prepupa and pupa to winged adult. The nymphal instar before prepupa secretes a waxy protective covering that remains in place throughout metamorphosis and these covers are characteristic of each family of scale insects. Most scale insect families (e.g. mealybugs, eriococcids, diaspidids) have rather loosely woven male covers, but male nymphs in the family Coccidae (soft scales) construct more rigid, glassy wax tests, which need a special mechanism for adult emergence. In the New Zealand male soft scales, a suture across the posterior quarter of the test enables the back plate to flex at a pair of hinges, to be raised up off the substrate, and so allow egress. The waxy back plate hinges are secreted by groups of tubular ducts on the abdominal dorsum of 2nd-instar males, during construction of the test. Scanning electron micrographs (SEMs) show the detail and diversity of hinge types. The wax tests of most New Zealand Coccidae, both female and male, are apparently unique in that they are constructed in rows of hexagonal plates, separated by sutures, however in the male test, the sutures are all fused except for the back plate suture. The two species in the endemic New Zealand genus Pounamococcus have male tests more like those of species in the Australian genus Austrolecanium.

Late outcome of isolated gastric bypass.

OBJECTIVE: To complete a long-term (>5 years) follow-up of patients undergoing isolated gastric bypass for severe obesity. SUMMARY BACKGROUND DATA: Previous experience as well as randomized trials suggested that the ideal operation for obesity should rely on manipulation of satiety rather than the production of malabsorption. Such an operation should incorporate a small gastric pouch of less than 30 mL placed in a dependent position on the lesser curvature of the stomach, not dependent on staples, and separated from the remaining stomach with a retrocolic, retrogastric Roux-en-Y gastrojejunostomy without external support. METHODS: The authors established an obesity clinic where patients were seen six times during the first year and semiannually thereafter. Emphasis was placed on defining success in terms of approximation to normal body-mass index. RESULTS: Of 274 patients, 243 (89%) were followed up for 5.5 +/- 1.5 years. Before surgery, the patients were obese (n = 13), morbidly obese (n = 134), or super-obese (n = 96). The obese and morbidly obese group achieved an excellent result, and the super-obese a good result. Individual results showed considerable variation from the mean. CONCLUSIONS: This study of isolated gastric bypass with a 5.5-year follow-up rate of 88.6% revealed a success rate of 93% in obese or morbidly obese patients and 57% in super-obese patients. Isolated gastric bypass compares favorably with biliopancreatic diversion in terms of weight loss, maximum weight loss, weight regain, current body-mass index, and percentage of patients with a body-mass index less than 35 kg/m2.

Plasma acylation stimulating protein, adipsin and lipids in non-obese and obese populations.

BACKGROUND: Acylation stimulating protein (ASP) is a potent stimulator of TG synthesis in human adipocytes. DESIGN: In the present study, we have analysed plasma ASP and adipsin levels and their relationships to plasma lipids in non-obese and obese groups. RESULTS: The results show that the frequency distribution of ASP is skewed but that of adipsin is normal in both groups. In the non-obese population, the mean levels of plasma ASP and adipsin were 20.2 nmol L-1 (median) and 66.6 +/- 19 nmol L-1 (mean) respectively. No difference was observed between men and women for each of the parameters. In the obese population, the median plasma ASP was increased by 246% (69.9 nmol L-1) and adipsin by 31% (87.0 +/- 22.7 nmol L-1) above that of the control group. Although the levels for men and women were not statistically different for adipsin, the median ASP plasma concentration was 1.9-fold higher in obese women than in obese men (71.8 nmol L-1 vs. 37.6 nmol L-1, P < 0.05). Best subset regression analysis provided a model with variables that best predict plasma ASP [r2 = 0.160, P < 0.008 for body mass index (BMI), P < 0.05 for triacylglycerol (TG), P < 0.03 for free fatty acid (FFA)] and plasma adipsin (r2 = 0.057, P < 0.017 for BMI) in a non-obese population. In obese subjects, the model was different for plasma ASP (P = NS for any of the variables) and plasma adipsin (r2 = 0.356, P < 0.008 for FFA, P < 0.0002 for BMI, P < 0.02 for age). There was no correlation between ASP and adipsin in either the non-obese or the obese group. CONCLUSION: The present data suggest involvement of the ASP/adipsin pathway in the pathogenesis of obesity.

Iron absorption and therapy after gastric bypass.

BACKGROUND: Iron deficiency anemia is a common complication of gastric bypass. The authors assessed the value of taking vitamin C with oral iron in correcting deficiencies in iron stores and anemia postoperatively. MATERIALS AND METHODS: Iron absorption tests were performed on 55 patients 3.2+/-2.0 years after isolated gastric bypass to identify those at higher risk for the late development of anemia. Twenty-nine of this group agreed to a therapeutic trial of iron alone or with vitamin C over a 2-month period. All 55 patients were followed up for 27.1+/-1.0 months following the study. RESULTS: The iron absorption test identified patients with low iron stores, as indicated by low serum ferritin, and those with sufficient absorption surface to benefit from oral iron. The addition of vitamin C appears to enhance the therapeutic effect of iron by correcting ferritin deficits (P < 0.01) and anemia (P < 0.05). Differences in intestine length bypassed by the operation (10 vs. 100 cm) did not affect late ferritin and hemoglobin values. CONCLUSION: This study suggests but does not prove that the addition of vitamin C to iron therapy after gastric bypass is more effective in restoring ferritin and hemoglobin than iron alone. These results are in contrast with the outcome 22.8 months later, when approximately 50% of study patients were again anemic. Closer follow-up of patients is urgently needed.

Exercise capacity and energy expenditure of morbidly obese and previously obese subjects.

OBJECTIVE: To determine whether morbidly obese and previously obese women fail to lose weight after gastric bypass surgery because of reduced energy expenditure, and whether a large, surgically induced, rapid weight loss improves exercise capacity on a treadmill. DESIGN: Cross-sectional study. PARTICIPANTS: Four groups of 5 subjects: 1) patients still obese 12 months after surgery (failure); 2) patients who achieved normal weight after surgery (success); 3) obese patients who had not yet undergone surgery (preoperative); and 4) nonobese (control) subjects. Four subjects in the preoperative group were studied again at 6 months postsurgery. MAIN OUTCOME MEASURES: Total daily energy expenditure (TDEE), and exercise capacity and peak oxygen consumption (VO2) during treadmill exercise. RESULTS: TDEE or energy expenditure (EE) above basal metabolic rate (when normalized for body size) was similar for all groups, but the absolute energy consumption was higher in the preoperative and failure groups. Treadmill endurance time was greater in the success than the failure and preoperative groups, and the endurance times of these 3 groups were less than those of the nonobese subjects. Peak VO2 body weight was similar in the success, failure and preoperative groups, which meant that the peak VO2 was lower in the success group than in the preoperative and failure groups. Six months after surgery, peak VO2 had not decreased in the preoperative group. CONCLUSION: Failure to lose weight after isolated gastric bypass surgery was not because of a lower level of activity. Aerobic capacity was impaired 1 year, but not 6 months, after a large weight loss. Exercise training may be appropriate to maintain absolute peak oxygen consumption.

Stomal ulcer after gastric bypass.

BACKGROUND: Stomal ulcer is a serious complication of gastrogastric fistula following Roux-en-Y gastric bypass for obesity. STUDY DESIGN: A 1-8 year continuous followup of 499 patients with gastric bypass in continuity (GB) and isolated gastric bypass (IGB) documented the incidence of fistula formation, development of stomal ulcer, stimulation of acid production within the gastric pouch, and response to treatment. RESULTS: In 123 GB patients, staple line disruption occurred in 36 (29%) and stomal ulcer occurred in 20 (16%). Gastrogastric fistula with stomal ulcer was significantly lower in 376 patients who underwent IGB, (ie, 11 patients [3%]). Significantly larger amounts of acid, a lower pH, and a greater time with a pH less than 2 were found in the gastric pouches of patients who developed stomal ulcer after Roux-en-Y gastric bypass. All patients had a perforated staple line. Successful closure of the staple line significantly decreased acid production and pH in the gastric pouch when tested before and after remedial operation with healing of stomal ulcers. CONCLUSIONS: Stomal ulcer after gastric bypass is the result of acid production in the bypassed stomach in the presence of a gastrogastric fistula. Separation of the gastric pouch from the main stomach decreases the incidence of fistula formation and stomal ulcer but does not eliminate it. Interposition of a well vascularized organ, the jejunum between the pouch and main stomach, is an attractive solution for patients who require remedial operations on the stomach and possibly for primary operations as well.

Does Genetic Predisposition Influence Surgical Results of Operations for Obesity?

BACKGROUND: There is a familial predisposition to obesity. We wished to document the incidence of obesity (BMI > 40 kg m(2)) in the immediate relatives (parents and siblings) of obese patients who were candidates for gastric restrictive surgery. We determined if a familial predisposition to obesity would influence the surgical results. METHODS: The height, weight and BMI were obtained in 1841 relatives of obese patients and in 1059 relatives of normal weight controls. The results of gastric surgery after 52.9 +/- 23.1 months were obtained in 44 patients with a familial history of obesity and in 34 patients without a familial history. RESULTS: Patients presenting with a BMI > 40 kg m(2) were 24.541 times more likely to have a first degree relative with morbid or super obesity than individuals in the control group. Mothers were twice as likely to be severely obese as fathers. A successful result (BMI < 35 kg m(2) or less than 50% excess weight) occurred 52.9 +/- 23.1 months in 77% of patients with a family history of obesity.and in 73% of patients without a familial predisposition (p = 0.79). CONCLUSIONS: There is a strong familial predisposition to obesity but over one-half of the immediate family members of obese patients have a BMI < 30 kg m(2). Gastric restrictive surgery induces satiety and produces a successful outcome regardless of familial predisposition. Patients who undergo surgery have a remarkably stable weight over the year prior to operation, suggesting they are defending a markedly elevated BMI.

Vitamin B-12 deficiency after gastric surgery for obesity.

Low serum vitamin B-12 concentrations after gastric bypass (GB) surgery for obesity were observed in 11 of 28 patients without detectable impairment of crystalline vitamin B-12 absorption. This was observed in 2 of 19 patients with vertical banded gastroplasty (VBG). In contrast, protein-bound vitamin B-12 absorption was markedly impaired, as demonstrated in eight of these patients after GB (n = 7) and VBG (n = 1). Correction of this impaired absorption occurred when protein-bound vitamin B-12 was incubated with an enzyme mixture before consumption. Simultaneous ingestion of the enzyme mixture with protein-bound vitamin B-12 did not improve absorption of the vitamin. In a separate experiment, 10 patients with a normal result from the Schilling test failed to correct low serum vitamin B-12 concentrations with a quantity of oral crystalline vitamin B-12 equal to the recommended dietary allowance of 2 micrograms, taken twice daily for 3 mo. Serum total homocysteine values declined during this interval. An oral daily dose of 350 micrograms crystalline vitamin B-12 raised the average serum vitamin B-12 concentration to an amount greater than the lower reference limit. A dose > 350 micrograms/d was required to raise all patients' vitamin B-12 concentrations above this concentration rather than just above the population mean. We conclude that because concentrations of oral crystalline vitamin B-12 were required to normalize serum vitamin B-12 concentrations, that a mechanism other than formation of a vitamin B-12 intrinsic factor complex is responsible for crystalline vitamin B-12 absorption after GB for obesity.

Stereotactic radiosurgery for glioblastoma: a final report of 31 patients.

From February 1989 to December 1992, 31 patients who presented with an initial pathological diagnosis of glioblastoma multiforme underwent tumor debulking or biopsy, stereotactic radiosurgery, and standard radiation therapy as part of their primary treatment. Presenting characteristics in the 22 men and nine women included a median age of 57 years, Karnofsky Performance Scale score median of 80, and median tumor volume of 16.4 cm3. Stereotactic radiosurgery delivered a central dose of 15 to 35 Gy with the isocenter location, collimator size, and beam paths individualized by means of three-dimensional software developed at the University of Wisconsin. The peripheral isodose line varied from 40% to 90% with a median of 72.5% and a mode of 80%. The mean follow-up period was 12.84 months with a median of 9.5 months. Statistical analysis was performed using Kaplan-Meier analysis and log-rank comparison of risk factor groups. The parameters of age, initial Karnofsky Performance Scale score, and biopsy were significantly different in patient survival from debulking; but no difference was noted between single and multiple isocenters and patterns of steroid requirement. Radiographic recurrences were divided by location into the following categories: central (within central stereotactic radiosurgery dose), 0; peripheral (within 2 cm of central dose), 19; and distant (> 2 cm), 4. There is no evidence of recurrence in five surviving patients. Actuarial 12-month survival was 37%, with a median survival of 9.5 months. These values are similar to previous results for surgery and standard radiotherapy alone. The results suggest that the curative value of radiosurgery is significantly limited by peripheral recurrences.

Stereotactic radiosurgery for glioblastoma multiforme.

From February 1989 to August 1992, 26 patients who presented with an initial pathological diagnosis of glioblastoma multiforme underwent tumor debulking (17) or biopsy (9), stereotactic radiosurgery (SR) and standard radiation therapy (dose range 50-66 Gy) as part of their primary tumor therapy. Presenting characteristics included median age of 55 years (range 20-79), Karnofsky Performance Score (KPS) median 82.5 (20-100), and median tumor volume 18.6 cm3 (2.2-59.7). SR collimator size ranged from 2.25 to 4 cm with a central dose of 15-35 Gy. Isocenter location, collimator size and beam paths were individualized using three-dimensional software such that the maximum possible solid angle was subtended without exceeding a 20% tumor dose gradient. The mean follow-up was 10.9 months (6-19.5) with a median of 9.5 months. Statistical analysis was performed using Kaplan-Meier actuarial analysis developing predicted 12-month survival rates. There were no significant differences noted in patient survival for the parameters of biopsy versus debulking, single versus multiple isocenters, age, initial KPS, and patterns of steroid requirement. Radiographic recurrences were divided by location into central (within central SR dose) = 0, peripheral (within 1 cm of central dose) = 16, and distant (< 1 cm) = 4. Predicted 12-month survival was 24%, with a median survival of 9.5 months. These values are similar to previous results for surgery and standard radiotherapy alone [1]. The results suggest that radiosurgery, when used as a mode of primary therapy, offers little or no benefit in quality of life or survival as recurrences occur immediately outside or distant to the central SR field.

A gastroplasty that avoids stapling in continuity.

BACKGROUND: Staple line perforations have been the principal cause of failure after vertical-banded gastroplasty in patients followed at least 4 years at our institution. In the present study an operation was devised that created a vertical-banded gastroplasty not dependent on staple lines to avoid this complication. METHODS: One hundred two patients with a body mass index (BMI) greater than 35 kg/m2 underwent vertical-banded gastroplasty from Jan. 1 to Dec. 30, 1986, with an orifice size of 45 to 47 mm external circumference and division between the vertical staple lines to prevent gastric pouch to gastric fundus fistula. RESULTS: Ninety-eight of the patients have been followed up for a minimum of 4 years. Sixty-two percent of patients obtained an excellent or good final result after 4.5 +/- 0.1 years. This was a BMI of less than 35 kg/m2 or less than 50% excess weight. This acceptable long-term result was achieved 90% of the time if the patient was obese (BMI, 35 to 40 kg/m2) before surgery and in 75% of patients who were morbidly obese (BMI, 40 to 50 kg/m2) but in only 30% of patients who were superobese (BMI > 50 kg/m2) before surgery. Staple line disruption was markedly reduced; however, stenosis or failure to lose weight or late weight gain required reoperation in 36% of the patients. CONCLUSIONS: Gastric bypass was superior to reversal or revision of the gastroplasty as a remedial operation. This study again questions the value of vertical-banded gastroplasty in the treatment of obesity even when staple line disruption is markedly diminished.

Results of the surgical treatment of obesity.

A prospective, randomized trial comparing vertical banded gastroplasty (VBG) and vertical gastric bypass (GB) for obesity was completed in 106 patients who did not differ in baseline body mass index (BMI = kg/m2) or length of follow-up. The goal of this surgery was to return patients to within 50% of their ideal weight, i.e., a body mass index less than 35 kg/m2, and to accomplish this while maintaining a low risk for malnutrition as well as other morbidity and mortality. Success was defined as a BMI less than 35 kg/m2 because the mortality risk increases rapidly above this degree of obesity. Surgical failures were encountered in 43% of the 54 patients in the VBG group, all of whom had division between the vertical staple lines. The main causes of failure were stenosis and enlargement of the gastroplasty orifice. Surgery failed in 23% of the GB-treated patients, due to perforation of the vertical staple line. An isolated gastric bypass (IGB) not dependent on staples was performed as the remedial operation for the failures of both VBG and GB. IGB was significantly better than VBG or GB, with a success rate of 83% compared with 39% for VBG and 58% for GB. Subsequent experience since completion of this randomized trial in 54 consecutive patients supports IGB for primary, as well as remedial, operations for the morbidly obese (BMI = 40 to 50 kg/m2), as well as for patients who are super obese (BMI greater than 50 kg/m2).

Late results of vertical banded gastroplasty for morbid and super obesity.

Two hundred one patients who underwent vertical banded gastroplasty have been followed up for a minimum of 2 years to more than 5 years. Staple line perforations occurred in 48% of patients, and 36% underwent reoperation. The instability of the operation becomes apparent only with careful follow-up. More than 50% of patients who maintained a small orifice of less than or equal to 11 mm in diameter and an intact staple line over 3 to 5 years achieved an excellent result (0% to 25% excess weight), which equals the best results in the literature for any gastric-limiting operation, whether bypass or gastroplasty. The results of this operation for super obesity (a body mass index greater than or equal to 50 kg/m2) are disappointing. Only 8% of these patients achieve an excellent result. Failure of vertical banded gastroplasty in the morbidly obese (body mass index of 40 to 50 kg/m2) is frequently technical, and a method that eliminates dependence on integrity of staples should be evaluated. Results should be reported so that unsatisfactory results are apparent. Mean weight loss and mean percent excess weight loss are both highly satisfactory in this study, whereas unsatisfactory results ranged from 10% to 21% for each of the 5 years of follow-up.

New retrovirus helper cells with almost no nucleotide sequence homology to retrovirus vectors.

We prepared retrovirus packaging cell lines containing gag-pol genes from spleen necrosis virus (expressed from a cytomegalovirus promoter and the simian virus 40 (SV40) polyadenylation sequences) and, on a separate vector, either the env gene from spleen necrosis virus (expressed from the Rous sarcoma virus promoter and the SV40 polyadenylation sequences) or the env gene from amphotropic murine leukemia virus (expressed from a cytomegalovirus promoter and the SV40 polyadenylation sequences). The nucleotide sequences in these packaging cell lines have almost no homology to the retrovirus vectors we used. Retrovirus vectors were produced from these new helper cell lines without any genetic interactions between the vectors and sequences in the helper cells and without transfer of the packaging sequences.

Nutrition after vertical banded gastroplasty.

The authors assessed the nutritional status of 60 morbidly obese patients by determining body composition, using multiple isotope dilution at 13.6 +/- 0.4 months following operation. Body weight was followed for an additional 12.3 +/- 0.8 months. Twenty-four patients lost more than 25% of their preoperative weight and were within 30% of ideal weight (a "good" result). At 1 year they had lost 41.4 +/- 1.8% of preoperative weight and the body mass index (BMI) decreased from 46.7 +/- 1.2 to 27.0 +/- 0.6 kg/m2. Despite rapid weight loss, malnutrition did not develop and their body composition became indistinguishable from that of normally nourished volunteers. Twenty-nine patients had a "satisfactory" result with more than 25% weight loss but were not within 30% of ideal. Their weight decreased by 34.8 +/- 1.0% as their BMI decreased from 55.4 +/- 1.2 to 36.0 +/- 0.8 kg/m2. Seven patients lost less than 25% of their preoperative weight (an "unsatisfactory" result). Malnutrition did not develop in any patient. In the authors' experience, in contrast to other weight reducing operations, vertical banded gastroplasty (VBG) results in rapid weight loss without the concomitant development of malnutrition even in patients who return to normal weight.

Instability of large direct repeats in retrovirus vectors.

Retrovirus vectors were constructed with large (0.85- to 1.3-kilobase-pair) direct repeats in their genomes. Deletions involving the direct repeats occurred at a high frequency. Deletions occurred both when the direct repeats were in tandem and when they were separated by additional sequences. These deletions occurred during virus replication.

Reliability of the total lymphocyte count as a parameter of nutrition.

To evaluate the total lymphocyte count as a means of nutritional assessment, body composition studies (a proven method of nutritional assessment) and total lymphocyte determinations were performed simultaneously in 153 patients. The total lymphocyte count correlated poorly with both the body cell mass and the nutritional state measured by the Nae to Ke ratio. For diagnosing malnutrition, the total lymphocyte count had a false-positive rate of 34% and a false-negative rate of 50%. In a group of 78 patients who received total parenteral nutrition for 2 weeks, the total lymphocyte count did not accurately reflect the nutritional changes. Due to its poor sensitivity and specificity, the total lymphocyte count is of no value as a measure of the nutritional state.