Results of a single-arm pilot study of 32P microparticles in unresectable locally advanced pancreatic adenocarcinoma with gemcitabine/nab-paclitaxel or FOLFIRINOX chemotherapy

Background

Unresectable locally advanced pancreatic cancer (LAPC) is generally managed with chemotherapy or chemoradiotherapy, but prognosis is poor with a median survival of ∼13 months (or up to 19 months in some studies). We assessed a novel brachytherapy device, using phosphorous-32 (³²P) microparticles, combined with standard-of-care chemotherapy.

Patients and methods

In this international, multicentre, single-arm, open-label pilot study, adult patients with histologically or cytologically proven unresectable LAPC received ³²P microparticles, via endoscopic ultrasound-guided fine-needle implantation, planned for week 4 of 5-fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX) or gemcitabine/nab-paclitaxel chemotherapy, per investigator’s choice. The primary endpoint was safety and tolerability measured using Common Terminology Criteria for Adverse Events version 4.0. The lead efficacy endpoint was local disease control rate at 16 weeks.

Results

Fifty patients were enrolled and received chemotherapy [intention-to-treat (ITT) population]. Forty-two patients received ³²P microparticle implantation [per protocol (PP) population]. A total of 1102 treatment-emergent adverse events (TEAEs) were reported in the ITT/safety population (956 PP), of which 167 (139 PP) were grade ≥3. In the PP population, 41 TEAEs in 16 (38.1%) patients were possibly or probably related to ³²P microparticles or implantation procedure, including 8 grade ≥3 in 3 (7.1%) patients, compared with 609 TEAEs in 42 (100%) patients attributed to chemotherapy, including 67 grade ≥3 in 28 patients (66.7%). The local disease control rate at 16 weeks was 82.0% (95% confidence interval: 68.6% to 90.9%) (ITT) and 90.5% (95% confidence interval: 77.4% to 97.3%) (PP). Tumour volume, carbohydrate antigen 19-9 levels, and metabolic tumour response at week 12 improved significantly. Ten patients (20.0% ITT; 23.8% PP) had surgical resection and median overall survival was 15.2 and 15.5 months for ITT and PP populations, respectively.

Conclusions

Endoscopic ultrasound-guided ³²P microparticle implantation has an acceptable safety profile. This study also suggests clinically relevant benefits of combining ³²P microparticles with standard-of-care systemic chemotherapy for patients with unresectable LAPC.

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PanCO is the first prospective study of intratumoural ³²P microparticles for locally advanced pancreatic cancer (LAPC).

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This single-arm study assessed a novel brachytherapy (³²P microparticles) combined with standard-of-care chemotherapy.

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Treatment-emergent adverse events attributable to ³²P microparticle implantation were relatively infrequent.

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Local disease control rate at 16 weeks (82%) and resection rate (20%) suggest a clinical benefit of ³²P microparticles.

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The results suggest that ³²P microparticles may address a significant unmet need in patients with unresectable LAPC.

Bacterial community structure and response to nitrogen amendments in Lake Shenandoah (VA, USA)

Microbial processes are critical to the function of freshwater ecosystems, yet we still do not fully understand the factors that shape freshwater microbial communities. Furthermore, freshwater ecosystems are particularly susceptible to effects of environmental change, including influx of exogenous nutrients such as nitrogen and phosphorus. To evaluate the impact of nitrogen loading on the microbial community structure of shallow freshwater lakes, water samples collected from Lake Shenandoah (Virginia, USA) were incubated with two concentrations of either ammonium, nitrate, or urea as a nitrogen source. The potential impact of these nitrogen compounds on the bacterial community structure was assessed via 16S rRNA amplicon sequencing. At the phylum level, the dominant taxa in Lake Shenandoah were comprised of Actinobacteria and Proteobacteria, which were not affected by exposure to the various nitrogen treatments. Overall, there was not a significant shift in the diversity of the bacterial community of Lake Shenandoah with the addition of nitrogen sources, indicating this shallow system may be constrained by other environmental factors.

Mesenchymal stem cells used for rabbit tendon repair can form ectopic bone and express alkaline phosphatase activity in constructs

Mesenchymal stem cells (MSCs) have been used to repair connective tissue defects in several animal models. Compared to "natural healing" controls (no added cells), MSC-collagen gel constructs in rabbit tendon defects significantly improve repair biomechanics. However, ectopic bone forms in 28% of MSC-treated rabbit tendons. To understand the source of bone formation, three studies were performed. In the first study, the hypothesis was tested that MSCs delivered during surgery contribute to bone formation in the in vivo repair site. Adjacent histological sections in the MSC-treated repair tissue were examined for pre-labeled MSCs and for cells showing positive alkaline phosphatase (ALP) activity. Both cells were observed in serial sections in regions of ectopic bone. Contralateral "natural healing" tendons lacked both markers. In the other two studies, the effects of osteogenic supplements and construct geometry (monolayer vs. 3-D) on ALP activity were studied to test three hypotheses: that rabbit MSCs increase ALP activity over time in monolayer culture conditions; that adding osteogenic inducing supplements to the culture medium increases cellular protein in monolayer culture; and that rabbit MSCs increase ALP activity both in monolayer and in 3-D constructs, with and without media supplements. Culture in monolayer under similar conditions to in vivo (as in the first study) did not increase ALP at 2 or 4 weeks. Medium designed to increase osteogenic activity significantly increased cell numbers (cellular protein increased by 260%) but did not affect ALP activity either in monolayer or 3-D constructs (p>0.12). However, MSCs in 3-D constructs exhibited higher ALP activity than cells in monolayer, both in the presence (p<0.045) and absence of supplement (p<0.005). These results suggest that in vitro conditions may critically influence cell differentiation and protein expression. Mechanisms responsible for these effects are currently under investigation.

Size, volume fraction, and nucleation of Stober silica nanoparticles

29Si NMR, small-angle X-ray scattering (SAXS), and dynamic light scattering (DLS) are used to monitor the synthesis of silica nanoparticles from the base-catalyzed hydrolysis of TEOS in methanol and ethanol. The reactions are conducted at a [TEOS] =0.5 M, low concentrations of ammonia ([NH(3)] =0.01-0.1 M), and [H(2)O] =1.1-4.4 M to resolve the initial size of the first nuclei and to follow their structural evolution. It is found that after an induction period where there is a buildup of singly hydrolyzed monomer, the first nuclei are fractal and open in structure. Interestingly, the nuclei are twice as large in ethanol (R(g) approximately 8 nm) as those in methanol (R(g) approximately 4 nm). The data suggest that the difference in primary particle size is possibly caused by a higher supersaturation ratio of the singly hydrolyzed monomer in methanol than in ethanol if it is assumed that the surface energy of the first nuclei is the same in methanol and ethanol. The particle number concentration and the volume fraction of the silica particles are calculated independently from the SAXS, DLS, and 29Si NMR results. Finally, the rate of nucleation is obtained from the particle number concentrations.

Rives-Stoppa procedure for repair of large incisional hernias: experience with 57 patients

BACKGROUND

The use of prosthetic materials in tension-free incisional hernia repairs has diminished reherniation rates markedly; however, infection, intestinal fistulization, and seroma formation have been reported after repairs. Use of the Rives-Stoppa procedure for incisional hernia repair, in which the prosthesis is placed between the rectus abdominis muscle and the posterior sheath, may reduce occurrence of these problems.

METHODS AND MATERIALS

Over a 6-year period 57 open abdominal wall incisional hernia repairs were performed using the Rives-Stoppa technique; 15 (26.3%) had previously undergone incisional hernia repair. The prosthetic materials used were polypropylene, expanded polytetrafluoroethylene (ePTFE), and ePTFE with perforations. The prosthesis size ranged from 8x8 cm to 20x28 cm (mean area 199.6 cm(2)). Follow-up consisted of an office visit 12 months postoperatively and at least one subsequent office visit or telephone interview; mean follow-up time was 34.9 months (range 11.7-81.9).

RESULTS

There were no hernia recurrences (except in one patient whose prosthesis was removed), gastrointestinal complications, fistulas, or deaths. Seromas occurred postoperatively in seven patients (12.3%). Two patients (3.5%) had wound infections that required removal of the prosthesis.

CONCLUSIONS

In this series the Rives-Stoppa technique had excellent long-term results, with minimal morbidity, in patients with large primary or recurrent incisional hernias. The absence of serious complications and hernia recurrences in patients with grafts in place suggests that the Rives-Stoppa procedure is the repair of choice in such patients.

An Australian experience with temozolomide for the treatment of recurrent high grade gliomas

Temozolomide has an evolving role in the treatment of high grade gliomas. Recent studies suggest that temozolomide is well tolerated and efficacious. This study retrospectively analysed the activity and toxicity associated with temozolomide at two Australian centres over a 24 month period. Fifty-six patients with recurrent high grade gliomas were treated with temozolomide. Patients received temozolomide orally at 150-200mg/m(2)daily, days 1-5, every 4 weeks. The median number of treatment cycles was 4 (1-12). Of the 56 patients, 15 (27%) achieved complete or partial response and 18 (32%) achieved minor response or stable disease. There were no episodes of febrile neutropenia and temozolomide was generally well tolerated. In conclusion, temozolomide is an active therapy in patients with recurrent high grade glioma and our results concord with published studies.

Enzymatic grafting of hexyloxyphenol onto chitosan to alter surface and rheological properties

An enzymatic method to graft hexyloxyphenol onto the biopolymer chitosan was studied. The method employs tyrosinase to convert the phenol into a reactive o-quinone, which undergoes subsequent nonenzymatic reaction with chitosan. Reactions were conducted under heterogeneous conditions using chitosan films and also under homogeneous conditions using aqueous methanolic mixtures capable of dissolving both hexyloxyphenol and chitosan. Tyrosinase was shown to catalyze the oxidation of hexyloxyphenol in such aqueous methanolic solutions. Chemical evidence for covalent grafting onto chitosan was provided by three independent spectroscopic approaches. Specifically, enzymatic modification resulted in (1) the appearance of broad absorbance in the 350-nm region of the UV/vis spectra for chitosan films; (2) changes in the NH bending and stretching regions of chitosan's IR spectra; and (3) a base-soluble material with (1)H-NMR signals characteristic of both chitosan and the alkyl groups of hexyloxyphenol. Hexyloxyphenol modification resulted in dramatic changes in chitosan's functional properties. On the basis of contact angle measurements, heterogeneous modification of a chitosan film yielded a hydrophobic surface. Homogeneously modified chitosan offered rheological properties characteristic of associating water-soluble polymers.

Chitin synthase in the filarial parasite, Brugia malayi

Fragments of putative chitin synthase (chs) genes from two filarial species (Brugia malayi and Dirofilaria immitis) were amplified by PCR using degenerate primers. The full genomic and cDNA sequences were obtained for the B. malayi chs gene (Bm-chs-1); the predicted amino acid sequence is highly similar, over a large region, to two CHS sequences of the nematode Caenorhabditis elegans and also to two insect CHS sequences. Bm-chs-1 is abundantly transcribed in B. malayi adult females, independent of their fertilization status, but is also expressed in males and microfilariae. Oocytes and early embryos contain large amounts of Bm-chs-1 transcript by in situ hybridization, but later stage embryos within the maternal uterus show little or no Bm-chs-1 transcript. No specific hybridization could be demonstrated in maternal somatic tissues. Polyclonal antibodies were raised against a peptide expressed from a recombinant cDNA fragment of Bm-chs-1; immunostaining detected CHS protein in oocytes and early to midstage embryos. These studies characterize a gene that is likely to be essential to oogenesis and embryonic development in a parasitic nematode. Because chitin synthesis and eggshell formation begin after fertilization, the presence of CHS protein in early oocytes suggests that the enzyme must be activated as a result of fertilization. These studies also demonstrate that chitin synthesis may not be restricted to eggshell formation in nematodes, as the Bm-chs-1 gene is transcribed in life cycle stages other than adult females.

Dysplasia complicating chronic ulcerative colitis: is immediate colectomy warranted?

PURPOSE

Inflammatory bowel disease surveillance strategies are designed to identify patients at greater than average risk for the development of invasive colonic carcinoma. Colonoscopic detection of mucosal dysplasia is considered the best available surveillance tool. However, the usefulness of dysplasia as a marker for cancer is uncertain. Furthermore, when dysplasia is found some suggest immediate colectomy, whereas others opt for continued surveillance. The aim of this study is to determine whether an association between dysplasia grade and cancer exists in patients with chronic ulcerative colitis, to ascertain the sensitivity, specificity, and positive predictive value of dysplasia as a cancer marker, and to clarify what action to take once dysplasia is discovered.

METHODS

The pathology reports of 590 patients who underwent total proctocolectomy or restorative proctocolectomy for chronic ulcerative colitis were reviewed for dysplasia, grade of dysplasia, presence of carcinoma, and tumor stage. One hundred sixty of these patients had undergone colonoscopic examination within the year before surgery. Findings from these studies were also reviewed.

RESULTS

Seventy-seven specimens (13.1 percent) contained at least one focus of dysplasia. Invasive cancers were found in 38 specimens (6.4 percent). Cancers were significantly more common among specimens with dysplastic changes (33/77 vs. 5/513; P < 0.001). Specimens with dysplasia of any grade were 36 times more likely to harbor invasive carcinoma. Stage III disease was found in association with indefinite or low-grade dysplasia in 5 of 26 (19.2 percent) of cases. Tumor stage did not correlate with dysplasia grade. Preoperative colonoscopy identified neoplastic changes in 57 (69.5 percent) cases. Dysplasia, cancer or both were missed in 25 cases. Lesions were correctly identified in only 31 (39.7 percent) of cases. Colonoscopically diagnosed dysplasia as a marker for synchronous cancer had a sensitivity of 81 percent and a specificity of 79 percent. The positive predictive value of a finding of preoperative dysplasia of any grade was 50 percent. The positive predictive value of a finding of low-grade dysplasia was 70 percent.

CONCLUSIONS

Dysplasia is an unreliable marker for the detection of synchronous carcinoma. However, when dysplasia of any grade is discovered at colonoscopy, the probability of a coexistent carcinoma is relatively high. Colonoscopic evidence of low-grade dysplasia has a higher positive predictive value than either dysplasia associated mass or lesion or high-grade dysplasia. Dysplasia grade does not predict tumor stage. Because advanced cancer can be found in association with dysplastic changes of any grade, confirmed dysplasia of any grade is an indication for colectomy.

Polydispersity during the Formation and Growth of the Stöber Silica Particles from Small-Angle X-Ray Scattering Measurements

The early stages of formation of Stöber silica particles have been investigated in situ during the hydrolysis and condensation of tetraethylorthosilicate under base-ammonia conditions in different alcoholic solvents. Time-resolved ultra-small-angle X-ray scattering by the entities produced in the solutions is used for structural characterization and monitoring of the growth kinetics of the particles. Our primary focus is to assess the polydispersity of the formed colloidal particles and its evolution as a function of time. We first applied a maximum entropy analysis of the scattering data to determine the size distribution and the time evolution of the size distribution of the colloidal particles. Second, we extended the cumulant method to analyze our earlier small-angle X-ray scattering data (H. Boukari, J. S. Lin, and M. T. Harris, J. Colloid Interface Sci. 194, 311, 1997; Chem. Mater. 9, 2376, 1997) and search for the presence of a distribution of fractal particles. The maximum entropy analysis indicates that there is a continuous nucleation of particles during the synthesis, and that this takes place within a relatively narrow size distribution. The cumulant analysis shows that, except at later times, the data are not adequate to confirm conclusively the presence of a distribution of fractal dimension at any time during the experiment. We discuss the impact of these results on growth kinetic models proposed for this system. Copyright 2000 Academic Press.

In vitro characterization of mesenchymal stem cell-seeded collagen scaffolds for tendon repair: effects of initial seeding density on contraction kinetics

Mesenchymal stem cells (MSCs) were isolated from bone marrow, culture-expanded, and then seeded at 1, 4, and 8 million cells/mL onto collagen gel constructs designed to augment tendon repair in vivo. To investigate the effects of seeding density on the contraction kinetics and cellular morphology, the contraction of the cell/collagen constructs was monitored over time up to 72 h in culture conditions. Constructs seeded at 4 and 8 million cells/mL showed no significant differences in their gross appearance and dimensions throughout the contraction process. By contrast, constructs seeded at 1 million cells/mL initially contracted more slowly and their diameters at 72 h were 62 to 73% larger than those seeded at higher densities. During contraction, MSCs reoriented and elongated significantly with time. Implants prepared at higher seeding densities showed more well aligned and elongated cell nuclei after 72 h of contraction. Changes in nuclear morphology of the MSCs in response to physical constraints provided by the contracted collagen fibrils may trigger differentiation pathways toward the fibroblastic lineage and influence the cell synthetic activity. Controlling the contraction and organization of the cells and matrix will be critical for successfully creating tissue engineered grafts.

Expression of proinflammatory genes during estrogen-induced inflammation of the rat prostate

BACKGROUND

Exposure of male Wistar rats to estradiol-17beta (E(2)) in the presence or absence of dihydrotestosterone propionate (DHT) was previously shown to result in prostate inflammation. The present study examines, for the first time, changes in the expression level of several proinflammatory genes during the course of this experimentally induced prostatitis.

METHODS

Adult male Wistar rats were given chronic exposure to E(2) + DHT by capsule implantation or were injected with E(2) for short-term exposure. Semiquantitative RT-PCR was employed to measure changes in proinflammatory transcript levels in the separated lobes of the prostate after various times of exposure to estrogen with or without DHT.

RESULTS

We observed an upregulation of IL-1beta, IL-6, MIP-2, and inducible nitric oxide synthase (iNOS) after only 4 days treatment with E(2). After 4 weeks of treatment with E(2) + DHT, a significant increase in transcript levels of IL-4, IL-5, IL-6, MIP-2, eotaxin, and iNOS was detected, while IL-1beta and TNF-alpha transcript levels only increased slightly. No increase in transcript levels for cyclooxygenase-2 (cox-2), IFN-gamma, IL-2, or IL-12 was observed.

CONCLUSIONS

Upregulation of proinflammatory transcripts occurred shortly after exposure to E(2) and well before any inflammatory cells were observed in the prostate. The pattern of gene expression resembled a T(H)2-type helper-cell response.

Reduce costs and improve patient satisfaction with home pre-operative bowel preparations

The results of a home-based preoperative bowel preparation, with and without the support of home care services, are compared with hospital-based preoperative bowel preparation. Length of stay, morbidity, and mortality rates; issues of patient satisfaction; and demographics are reported. The method and tools used in planning, implementing, and evaluating the home preoperative bowel preparation program are also shared. Other issues discussed are the healthcare market forces that promote an increased value of care. Economic and patient satisfaction considerations by employers, payers, and patients; the increasing influence of patient choice on healthcare provider selection and care setting preferences; the nursing workforce issues related to the impending shortage; and issues of regulatory and accrediting agencies are also discussed.

Twelve-year experience with expanded polytetrafluoroethylene in the repair of abdominal wall defects

BACKGROUND

A prosthetic device must be used to repair ventral hernias in patients with insufficient tissue for a tension-free primary closure. Several prosthetic materials have been employed for this purpose, with varying results. We here review a long experience with the use of expanded polytetrafluoroethylene (ePTFE) patches in the open repair of large abdominal wall defects.

METHODS

Demographic, operative, follow-up, and histologic data were recorded and analyzed for all patients in a surgical practice who were treated for large abdominal wall defects with open repair using ePTFE patches between November 1983 and March 1996.

RESULTS

Ventral hernia repairs using an ePTFE patch were performed in 98 patients. In 48 (49%), the patient had already undergone at least one previous ventral hernia repair. Of the 98 operations, 78 were full-thickness repairs, 11 were Rives-Stoppa procedures, and 9 were onlay operations. Complications included 5 seromas, 3 fistulas related to removal of a previously implanted prosthesis, and 9 infections. In addition, 10 patients developed recurrent hernias not related to explantation of the patch because of infection or fistula. In 3 patients, infections were treated successfully without removal of the patch. There were no complications related to adhesions, erosion of the patch into the viscera, or bowel obstruction. Histologic studies of longterm ePTFE implants showed excellent fibrous tissue ingrowth and minimal foreign body response.

CONCLUSIONS

Our long-term clinical experience indicates that prosthetic patches of ePTFE are safe and effective when used in the repair of large abdominal wall defects that cannot be closed primarily. Operative complications were within acceptable limits, as was the reherniation rate.

Small-Angle X-Ray Scattering Study of the Formation of Colloidal Silica Particles from Alkoxides: Primary Particles or Not?

The formation of colloidal silica particles and the dynamics of the nanostructure of the particles are investigated by small-angle X-ray scattering (SAXS) technique. Solute concentrations of 0.5 M tetraethylorthosilicate (TEOS), 1.1 or 2.2 M water (H2O), and 0.04 or 0.1 M ammonia base (NH3) in ethanol were used to obtain reaction conditions as close to those of the Stober method as possible and to have reaction kinetics that were slow enough to probe the changes in the nanostructure of the growing particles and to obtain good statistics from the SAXS measurements. We measured the changes in the radius of gyration and the fractal dimension as a function of time during growth. Remarkably, we find that, after an induction period, the first particles to appear in the solution have a radius of gyration of approximately 10 nm and are mass fractals characterized by their polymeric, open structure. This stage is followed by an intraparticle densification process and smoothing of the interface, leading to the usual compact nonfractal, stable structures. The growth models proposed so far cannot account for the observed continuous changes of stages during the formation and growth of the particles. Copyright 1997 Academic Press. Copyright 1997Academic Press

Assessing Extreme Models of the Stober Synthesis Using Transients under a Range of Initial Composition

29Si-NMR, conductimetry, and photon correlation spectroscopy are used to monitor the temporal profile of intermediate concentrations in Stober synthesis (i.e., ammonia-catalyzed hydrolysis of tetraethoxysilane in a batch reactor). Extreme models of the process are assessed by examining the effect of initial composition on these transients (over a wider range of composition than attempted previously). The trends with initial composition suggest that the nucleation is rate-limited by the hydrolysis of the singly hydrolyzed monomer, the product of which probably phase separates. Moreover, the trends are consistent with the aggregation model discussed by G. H. Bogush and C. F. Zukoski (J. Colloid Interface Sci. 142, 1, 19 (1991) and by M. T. Harris (Ph.D. dissertation, Univ. of Tennessee, 1992). The trends are not consistent with a growth model without aggregation. Copyright 1997 Academic Press. Copyright 1997Academic Press

Restorative proctocolectomy in patients older than fifty years

PURPOSE

This study was undertaken to compare functional results, complications, preoperative durations of disease, and rates of dysplasia and neoplasia between older and younger chronic ulcerative colitis patients undergoing restorative proctocolectomy (RPC) with mucosectomy.

METHODS

A total of 392 patients with a preoperative diagnosis of chronic ulcerative colitis underwent elective RPC with mucosection and handsewn ileoanal anastomosis. Pathologic reports were reviewed, with specific reference to findings of dysplasia or cancer. Functional results concerning the number of bowel movements per 24 hour period and the incidence of fecal soilage were obtained by direct or telephone patient interview.

FINDINGS

Group I consisted of 326 patients aged 5 to 49 (mean, 30.9) years and 160 women. Group II comprised 66 patients aged 50 to 74 (mean, 56.9) years and 29 women. Duration of disease was significantly longer in the older group (6.2 vs. 15.6 years; P < 0.001). The older group had significantly higher rates of dysplasia (29/326 vs. 19/66; P < 0.0001) and malignancy (14/326 vs. 9/66; P = 0.003). Rates of complication, hospital days following RPC, and total hospital days for all causes were comparable between groups. Perfect day-time continence was observed in 81.6 percent of Group I and 80 percent of Group II patients (213/261 vs. 40/50; P = 0.79). Perfect continence during sleep was observed in 65.1 percent of Group I and 62 percent of Group II patients (170/261 vs. 31/50; P = 0.67). Mean number of bowel movements per 24 hour period for Group I was 6.3 +/- 0.2 and for Group II was 7.4 +/- 0.5. Mean difference, one movement per 24 hours, was not significant (95 percent confidence interval, -0.02 to 2.1; t = 1.95, P = 0.055).

CONCLUSIONS

We conclude that patients older than 50 years are suitable candidates for RPC with mucosectomy. Functional results and complication rates are similar to those observed among younger patients. Patients older than 50 years have a significantly higher rate of concurrent dysplasia and malignant degeneration than younger patients, most probably because of a longer duration of disease. RPC with mucosal excision potentially lowers this risk by elimination of all colorectal mucosa.

Laparoscopic-assisted intestinal resection for Crohn's disease. Which patients are good candidates?

This study was undertaken to determine preoperative criteria indicating which patients with Crohn's disease are most amenable to minimally invasive intestinal resection. Laparoscopic-assisted intestinal resection was attempted in 25 patients with Crohn's disease. Preoperative assessment of all patients included physical examination and contrast radiography. Laparoscopic intestinal resection was successfully completed in 19 patients. Four patients in whom both palpable mass and fistulous disease were present required conversion to open surgery. One patient found during surgery to have a fistula required conversion, as did one patient who had undergone previous ileocolic resection. In patients treated laparoscopically, oral alimentation, discontinuation of parenteral narcotics, and hospital discharge were possible at an average of 3.4, 4.2, and 6.5 days postsurgery, respectively. Patients operated upon using open techniques stayed in the hospital an average of 8.5 days. Laparoscopic-assisted intestinal resection is beneficial to selected patients with Crohn's disease. The presence of both a fixed mass and fistula on preoperative evaluation is predictive of conversion to open laparotomy and should be considered a relative contraindication. Patients with either a fixed mass or a fistula alone are more amenable to laparoscopic-assisted intestinal resection, while patients with primary uncomplicated Crohn's disease appear to be ideally suited to minimally invasive surgery.

Gastrointestinal histoplasmosis in a patient with acquired immune deficiency syndrome

In otherwise healthy individuals, disease caused by the fungus Histoplasma capsulatum manifests itself as a self-limiting pulmonary infection. Dissemination of the organisms may occur in a setting of compromised cellular immunity. Gastrointestinal involvement occurs in many such cases, but rarely it is clinically obvious and the disease seldom comes to the attention of the general surgeon. However, with the increasing incidence of acquired immunodeficiency syndromes, general surgeons are managing more of these patients than in the past. In our report, we describe a patient with acquired immunodeficiency syndrome who presented with gastrointestinal histoplasmosis.

Laparoscopic-assisted intestinal resection for Crohn's disease

PURPOSE

The inflammatory process associated with Crohn's disease often makes dissection difficult, even in "open" surgery. This study was undertaken to determine if dissection and resection could be performed laparoscopically and whether it would benefit this group of patients.

METHODS

Between November 1992 and November 1994, laparoscopic-assisted intestinal resection was attempted in 18 patients with Crohn's disease and was successfully completed in 14. One patient had ileal disease, requiring ileal resection with ileoileal anastomosis. The remainder had disease requiring ileocolic resections. Muscle-splitting incisions averaging 5 cm in length were made to facilitate removal of specimens.

RESULTS

Commencement of oral alimentation was possible at an average of 3.6 (range, 1-7) days postoperatively. Discharge occurred at an average of 6.6 (range, 4-9) postoperative days. In comparison, 14 patients operated on by the authors for the same disease in the open manner during the past six months stayed an average of 8.5 (range, 5-14) postoperative days. Postoperative complications were minimal.

CONCLUSIONS

On the basis of this initial study, it appears that laparoscopic-assisted intestinal resection can be readily performed in patients with Crohn's disease. In our early experience, we have found that laparoscopic mobilization and resection may be difficult or impossible in patients with large fixed masses, multiple complex fistulas, or recurrent Crohn's disease. Extraction incisions are frequently so large in these patients that they do not derive the same benefits from laparoscopic surgery that are enjoyed by patients without these findings. Most patients having laparoscopic resections eat earlier, may require fewer narcotics, and are able to be discharged from the hospital an average of two days earlier than patients operated on in an open manner. In addition, it appears that laparoscopic-assisted intestinal resection results in a shorter, easier convalescence and an earlier return to full activity.

Restorative proctocolectomy without diverting ileostomy

PURPOSE

Restorative proctocolectomy (RPC) by abdominal colectomy and ileal pouch-anal anastomosis (IPAA) in the setting of chronic ulcerative colitis (CUC) and familial adenomatous polyposis (FAP) has gained widespread popularity among surgeons and patients. Traditionally, temporary loop ileostomy has been established proximal to the ileal pouch in an effort to mitigate the effects of any suture line complications that may occur. This study compares functional results and complications encountered after RPC with mucosectomy with and without temporary ileostomy.

METHODS

One hundred forty-three consecutive patients with either CUC or FAP underwent RPC including mucosectomy and ileal "J" reservoir. Proximal loop ileostomy was performed in 69 patients, and ileostomy was omitted in 74. Ileostomy was omitted if the patient was taking no immunosuppressives and less than 20 mg of prednisone daily in the month preceding surgery, the anastomosis was absolutely tension-free, and blood supply to the pouch was excellent.

RESULTS

There were no perioperative deaths. There were two instances of pelvic abscess, one in the diverted group and one in the nondiverted group. Occurrence of IPAA suture line dehiscence was not significantly different between the two groups (ileostomy, 4/69 (6 percent), vs. no ileostomy, 6/74 (8 percent); P > 0.05). Comparison of 129 patients with colitis with and without diversion also failed to demonstrate a significant difference with regard to IPAA suture line dehiscence (ileostomy, 4/69 (6 percent) vs. 4/60 (7 percent); P > 0.05). Frequency of bowel movements and continence were the same in both groups and were comparable with results obtained without mucosectomy. Mean hospital stay at time of RPC for the nondiverted group was significantly longer (12 days vs. 10 days; P = 0.0004). Significantly fewer patients without an ileostomy were hospitalized for partial intestinal obstruction (ileostomy, 13/69 (19 percent), vs. no ileostomy, 3/74 (4 percent); P = 0.02), and significantly fewer required enterolysis (ileostomy, 7/69 (10 percent), vs. no ileostomy, 1/74 (1 percent); P = 0.04). On average, patients without an ileostomy spent significantly fewer total days in the hospital (17 vs. 24; P = 0.002).

CONCLUSION

Restorative proctocolectomy with mucosectomy and without ileostomy is the procedure of choice for selected patients with FAP and CUC. Septic complications and functional results are similar to those seen in patients managed with a stoma. Anastomotic leakage, when it occurs, can be safely managed in most cases without surgery. RPC without ileostomy results in significantly fewer episodes of intestinal obstruction, fewer instances of re-exploration, and fewer total days in the hospital.

Colonoscopic features of colonic anastomoses

Colonic anastomoses are frequently encountered, but their endoscopic features have never been adequately characterized. Results of 117 consecutive colonoscopies in patients with colonic anastomoses were prospectively studied during a 12-month period. Anastomoses were photographed, videotaped, and reviewed by the authors. The age range of patients was 18 to 87 years, and interval from surgery extended to 42 years. An equal number of right and left colonic resections were encountered; 9 patients had subtotal colectomies. Ninety-two anastomoses were hand-sewn, and 25 were stapled. Ileal pouch-anal anastomoses were not included. Nine common anastomotic features were identified with the following frequency of occurrence: neovascularity, 105 (89.7%); white anastomotic edge, 64 (54.7%); disruption of haustral pattern, 64 (54.7%); radial suture tracks, 35/92 (38.0%); exposed suture, 11/92 (11.9%); exposed staples, 6/25 (24%); scar tissue adjacent to anastomotic line, 8 (6.8%); nondistensibility of anastomosis, 5 (4.3%); blind colonic pouch, 10 (8.5%). No recurrent carcinomas were noted. The site of seven anastomoses (5.5%) could not be identified. Six of these patients underwent endoscopy more than 8 years postoperatively. Of the remaining 110 patients, 94 (85.5%) had between two and four of the above features identified. In three of four patients who required dilation because of strictures, neovascularity was not seen. We conclude that colonic anastomoses have characteristic endoscopic features. These features can be used as landmarks for definitive identification of anastomotic sites at colonoscopy. The lack of neovascularity at a colonic anastomosis may be an indicator of relative ischemia, predisposing to stricture formation.

A case of intrauterine fetal death associated with maternal Campylobacter coli bacteraemia

Campylobacter species are known to cause infectious abortion in domestic animals. In humans, Campylobacter are an important cause of enteritis, an occasional cause of systemic infection and have had a rare association with abortion and perinatal infection. A case history of spontaneous abortion, at 26 weeks' duration, associated with maternal bacteraemia, due to Campylobacter coli is presented. Transmission, pathogenesis, treatment, and the need for further investigation are discussed.

Systemic diseases affecting the mesenteric circulation

The mesenteric circulation is acutely sensitive to processes that affect the entire body. Such systemic diseases and syndromes are reviewed with particular emphasis on the mechanisms by which they influence the mesenteric vasculature and blood flow.

Toxic shock syndrome after pilonidal cystectomy. Report of a case

Toxic shock syndrome is an uncommon disease associated with staphylococcal infections. Although most frequently reported in menstruating women and associated with tampon use, toxic shock syndrome has been described following many types of surgical procedures. In this report we describe a case of toxic shock syndrome occurring in a previously healthy young man after elective surgery for a pilonidal cyst.

Expression of asialo GM1 by both Thy-1-positive and Thy-1-negative lymphocytes: evidence for modification of asialo GM1 by sialic acid

In order to determine the extent to which Thy-1-positive and Thy-1-negative lymphocytes express the asialo GM1 antigen, lymphocytes in normal spleen and lymph node were examined for simultaneous expression of the asialo GM1 and Thy-1.2 determinants. The results presented herein demonstrate that 55-57% of Thy-1.2-positive cells in spleen and 61-70% of Thy-1.2-positive cells in lymph node express asialo GM1. Furthermore, a significant frequency of Thy-1-negative cells in spleen (12-19%) and in lymph node (28-32%) also express asialo GM1. Since asialo GM1 has previously been shown to be absent on Ig-positive lymphocytes [9], these results establish that asialo GM1 is a marker shared by lymphocytes belonging to the T-cell lineage and lymphocytes apparently not committed to the T-cell to the T-cell lineage, most probably including natural killer (NK) cells. The implication of this finding as to the controversy regarding the possible relation of NK cells to T cells is discussed. Pretreatment of lymphocytes from spleen, thymus and lymph node with neuraminidase resulted in subsequent reactivity of 80-90% of these cells with anti-asialo GM1 anti-bodies. A smaller increase in asialo GM1 detection after neuraminidase treatment was seen with bone-marrow cells (65%). Protease treatment did not affect the subsequent reactivity of lymphocytes with anti-asialo GM1 antibodies. It is concluded that in situ enzymatic modification of asialo GM1 by the addition of sialic acid may be an important regulatory event in lymphocyte differentiation.

Selective expression of asialo GM1 on maturational subsets of lymphocytes in normal and athymic mice

In an attempt to clarify the restriction of asialo GM1 expression, the presence of asialo GM1 positive cells in the lymphoid tissues of normal and athymic mice was examined using affinity-purified monospecific anti-asialo GM1 antibodies and a FACS-II. The results presented herein demonstrate that a significant frequency of asialo GM1-positive cells can be detected in the primary lymphoid tissues (bone marrow and thymus) as well as in the secondary lymphoid tissues (spleen and lymph nodes). The observed expression of asialo GM1 within the T-cell lineage is, in general, consistent with the previously proposed restriction of asialo GM1 expression to mature T cells. However, the demonstration that a significant frequency of asialo GM1-positive cells is detectable in bone marrow of normal mice, as well as in spleen and bone marrow of athymic mice, establishes that a substantial number of lymphocytes not committed to the T-cell lineage and/or pre-T cells also express the asialo Gm1 antigen. These results indicate that the asialo GM1 marker may be an important tool for following T differentiation from the multipotential stem cell to the functionally mature T cell.