The empty pelvis syndrome: a core data set from the PelvEx collaborative

BACKGROUND

Empty pelvis syndrome (EPS) is a significant source of morbidity following pelvic exenteration (PE), but is undefined. EPS outcome reporting and descriptors of radicality of PE are inconsistent; therefore, the best approaches for prevention are unknown. To facilitate future research into EPS, the aim of this study is to define a measurable core outcome set, core descriptor set and written definition for EPS. Consensus on strategies to mitigate EPS was also explored.

METHOD

Three-stage consensus methodology was used: longlisting with systematic review, healthcare professional event, patient engagement, and Delphi-piloting; shortlisting with two rounds of modified Delphi; and a confirmatory stage using a modified nominal group technique. This included a selection of measurement instruments, and iterative generation of a written EPS definition.

RESULTS

One hundred and three and 119 participants took part in the modified Delphi and consensus meetings, respectively. This encompassed international patient and healthcare professional representation with multidisciplinary input. Seventy statements were longlisted, seven core outcomes (bowel obstruction, enteroperineal fistula, chronic perineal sinus, infected pelvic collection, bowel obstruction, morbidity from reconstruction, re-intervention, and quality of life), and four core descriptors (magnitude of surgery, radiotherapy-induced damage, methods of reconstruction, and changes in volume of pelvic dead space) reached consensus-where applicable, measurement of these outcomes and descriptors was defined. A written definition for EPS was agreed.

CONCLUSIONS

EPS is an area of unmet research and clinical need. This study provides an agreed definition and core data set for EPS to facilitate further research.

A Full Bladder Is Not Needed for the Male Stress Incontinence Grading Scale

INTRODUCTION

Our objectives were to evaluate the Male Stress Incontinence Grading Scale to stratify male patients with stress urinary incontinence for either artificial urinary sphincter or sling using a standing cough test and determine if an emptier bladder at the time of assessment carries increased risk of treatment failure.

METHODS

Retrospective chart review of male patients undergoing sling and artificial urinary sphincter placement. The standing cough test score and bladder scan results were documented at initial evaluation.

RESULTS

Forty patients underwent sling and 43 underwent naïve artificial sphincter placement. Median follow-up was 7.11 months. Thirty-six/forty slings had complete incontinence resolution or reduction to a safety pad vs 40/43 after sphincter (90% vs 93%, P = .62). Four sling patients (10%) had persistence or recurrence of incontinence. Cough test scores were similar between sling failure (67% grade 0, 33% grade 1) and success groups (83% grade 0, 3% grade 1, 14% grade 2). Bladder scan mean was 18.5 cc in the sling failure (SD 21.1) and 38.0 cc in the success groups (38.3), with 32% of success patients having bladder scans of 0 cc, and 63% of < 50 cc. Mean for sphincter patients was 45 cc (56.9). Ten patients with scan = 0 and 7 patients with scans < 30 cc demonstrated grade 4 incontinence.

CONCLUSIONS

Cough test is a noninvasive, reliable tool to assess stress urinary incontinence severity. Our data suggest it is reliable even when bladders are nearly empty and can effectively stratify patients for sling vs artificial urinary sphincter with a high rate of success.

Minimum standards of pelvic exenterative practice: PelvEx Collaborative guideline

This document outlines the important aspects of caring for patients who have been diagnosed with advanced pelvic cancer. It is primarily aimed at those who are establishing a service that adequately caters to this patient group. The relevant literature has been summarized and an attempt made to simplify the approach to management of these complex cases.

Targeted Therapies for the Neurofibromatoses

Over the past several years, management of the tumors associated with the neurofibromatoses has been recognized to often require approaches that are distinct from their spontaneous counterparts. Focus has shifted to therapy aimed at minimizing symptoms given the risks of persistent, multiple tumors and new tumor growth. In this review, we will highlight the translation of preclinical data to therapeutic trials for patients with neurofibromatosis, particularly neurofibromatosis type 1 and neurofibromatosis type 2. Successful inhibition of MEK for patients with neurofibromatosis type 1 and progressive optic pathway gliomas or plexiform neurofibromas has been a significant advancement in patient care. Similar success for the malignant NF1 tumors, such as high-grade gliomas and malignant peripheral nerve sheath tumors, has not yet been achieved; nor has significant progress been made for patients with either neurofibromatosis type 2 or schwannomatosis, although efforts are ongoing.

Insights into the Pathogenesis of NF1-Associated Neoplasms

Neurofibromatosis type 1 (NF1) is one of the most common neurocutaneous genetic disorders, presenting with different cutaneous features such as café-au-lait macules, intertriginous skin freckling, and neurofibromas. Although most of the disease manifestations are benign, patients are at risk for a variety of malignancies, including malignant transformation of plexiform neurofibromas. Numerous studies have investigated the mechanisms by which these characteristic neurofibromas develop, with progress made toward unraveling the various players involved in their complex pathogenesis. In this review, we summarize the current understanding of the cells that give rise to NF1 neoplasms as well as the molecular mechanisms and cellular changes that confer tumorigenic potential. We also discuss the role of the tumor microenvironment and the key aspects of its various cell types that contribute to NF1-associated tumorigenesis. An increased understanding of these intrinsic and extrinsic components is critical for developing novel therapeutic approaches for affected patients.

Unbiased Microbiome and Metabolomic Profiling of Fecal Samples from Patients with Melanoma

Gut microbiota influence and modulate host immune responses. In preclinical cancer models, mice lacking gut microbiota have a markedly diminished response to immune checkpoint inhibitor therapy. Further, in melanoma patients, specific commensal gut microbiota have been associated with a positive clinical response to immunotherapy. In order to study the gut microbiome and metabolome, we have developed methods for fecal sample collection and processing, microbiome and metabolome profiling, and bioinformatic analysis. This protocol will be a useful tool for interrogating the taxonomic composition and functional output of a melanoma patient's gut microbiome.

Simultaneous pelvic exenteration and liver resection for primary rectal cancer with synchronous liver metastases: results from the PelvEx Collaborative

AIM

At presentation, 15-20% of patients with rectal cancer already have synchronous liver metastases. The aim of this study was to determine the surgical and survival outcomes in patients with advanced rectal cancer who underwent combined pelvic exenteration and liver (oligometastatic) resection.

METHOD

Data from 20 international institutions that performed simultaneous pelvic exenteration and liver resection between 2007 and 2017 were accumulated. Primarily, we examined perioperative outcomes, morbidity and mortality. We also assessed the impact that margin status had on survival.

RESULTS

Of 128 patients, 72 (56.2%) were men with a median age of 60 years [interquartile range (IQR) 15 years]. The median size of the liver oligometastatic deposits was 2 cm (IQR 1.8 cm). The median duration of surgery was 406 min (IQR 240 min), with a median blood loss of 1090 ml (IQR 2010 ml). A negative resection margin (R0 resection) was achieved in 73.5% of pelvic exenterations and 66.4% of liver resections. The 30-day mortality rate was 1.6%, and 32% of patients had a major postoperative complication. The 5-year overall survival for patients in whom an R0 resection of both primary and metastatic disease was achieved was 54.6% compared with 20% for those with an R1/R2 resection (P = 0.006).

CONCLUSION

Simultaneous pelvic exenteration and liver resection is feasible, with acceptable morbidity and mortality. Simultaneous resection should only be performed where an R0 resection of both pelvic and hepatic disease is anticipated.

Quantitative Analysis of Spinal Canal Areas in the Lumbar Spine: An Imaging Informatics and Machine Learning Study

BACKGROUND AND PURPOSE

Quantitative imaging biomarkers have not been established for the diagnosis of spinal canal stenosis. This work aimed to lay the groundwork to establish such biomarkers by leveraging the developments in machine learning and medical imaging informatics.

MATERIALS AND METHODS

Machine learning algorithms were trained to segment lumbar spinal canal areas on axial views and intervertebral discs on sagittal views of lumbar MRIs. These were used to measure spinal canal areas at each lumbar level (L1 through L5). Machine-generated delineations were compared with 2 sets of human-generated delineations to validate the proposed techniques. Then, we use these machine learning methods to delineate and measure lumbar spinal canal areas in a normative cohort and to analyze their variation with respect to age, sex, and height using a variable-intercept mixed model.

RESULTS

We established that machine-generated delineations are comparable with human-generated segmentations. Spinal canal areas as measured by machine are statistically significantly correlated with height (P < .05) but not with age or sex.

CONCLUSIONS

Our machine learning methodology demonstrates that this important anatomic structure can be accurately detected and quantitatively measured without human input in a manner comparable with that of human raters. Anatomic deviations measured against the normative model established here could be used to flag spinal stenosis in the future.

Effective bioreactor pH control using only sparging gases

pH control is critical in bioreactor operations, typically realized through a two-sided control loop, where CO₂ sparging and base addition are used in bicarbonate-buffered media. Though a common approach, base addition could compromise culture performance due to the potential impact from pH excursions and osmolality increase in large-scale bioreactors. In this study, the feasibility of utilizing control of sparge gas composition as part of the pH control loop was assessed in Chinese hamster ovary (CHO) fed-batch cultures. Fine pH control was evaluated in multiple processes at different setpoints in small-scale ambr®250 bioreactors. Desired culture pH setpoints were successfully maintained via air sparge feedback control. As part of the pH control loop, air sparging was increased to improve CO₂ removal automatically, hence increase culture pH, and vice versa. The effectiveness of this pH control strategy was seamlessly transferred from ambr®250 to 200 L scale, demonstrating scalability of the proposed methodology. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2743, 2019.

Validation of the Sleep-Wake Scoring of a New Wrist-Worn Sleep Monitoring Device

STUDY OBJECTIVES

To test the sleep-wake scoring reliability of a new wrist-worn sleep monitoring device.

METHODS

Twenty-seven adult good sleepers underwent 1 night of polysomnography (PSG) while wearing both the new device (myCadian [MC]; CurAegis Technologies, Rochester, New York, United States) and commercially available actigraphy (Actiwatch 2 [AW]; Philips Respironics, Murrysville, Pennsylvania, United States) on their nondominant wrist. PSG tests were manually stage scored. After excluding missing data, 20 participants had full-night data on all three devices with 17,734 total 30-second epochs. Using PSG as the gold standard, pooled epoch-by-epoch agreement for sleep and wake was calculated for each device using percent agreement and Cohen kappa statistic. Positive predictive values for both sleep and wake epochs, as well as sleep continuity statistics, were calculated.

RESULTS

Percent agreement with PSG-scored wake and sleep was 91.3% for MC (kappa = 0.67) and 87.7% for AW (kappa = 0.50). Positive predictive values for sleep epochs were 94.4% and 90.8% for MC and AW, respectively, and 74.5% and 65.6% for wake. Both devices underestimated wake and overestimated sleep compared to PSG. Descriptively, compared to PSG, sleep latency was higher with MC and wake after sleep onset higher with AW. Total sleep time and sleep efficiency were more similar across devices.

CONCLUSIONS

The kappa statistic for MC is consistent with a high level of agreement with PSG. Overall, the reliability of MC compared to PSG scoring was slightly more favorable than that of AW. Findings suggest that MC provides reliable sleep-wake scoring during a nocturnal sleep period for good sleepers.

Increased blood-oxygen binding affinity in Tibetan and Han Chinese residents at 4200 m

High-altitude natives are challenged by hypoxia, and a potential compensatory mechanism could be reduced blood oxygen-binding affinity (P50), as seen in several high-altitude mammalian species. In 21 Qinghai Tibetan and nine Han Chinese men, all resident at 4200 m, standard P50 was calculated from measurements of arterial PO2 and forehead oximeter oxygen saturation, which was validated in a separate examination of 13 healthy subjects residing at sea level. In both Tibetans and Han Chinese, standard P50 was 24.5 ± 1.4 and 24.5 ± 2.0 mmHg, respectively, and was lower than in the sea-level subjects (26.2 ± 0.6 mmHg, P < 0.01). There was no relationship between P50 and haemoglobin concentration (the latter ranging from 15.2 to 22.9 g dl(-1) in Tibetans). During peak exercise, P50 was not associated with alveolar-arterial PO2 difference or peak O2 uptake per kilogram. There appears to be no apparent benefit of a lower P50 in this adult high-altitude Tibetan population.

Analytical modeling and numerical simulation of forces in an endoluminal graft

PURPOSE

To utilize mathematical analysis and computational fluid dynamics (CFD) to investigate the forces acting within the pressurized aorta and upon a stent-graft and how these forces may affect the ongoing performance of the stent-graft.

METHODS

Analytical force balance analysis and CFD simulations using the Fluent code were used to mimic blood flow through a bifurcated stent-graft in a person at rest. Steady-state blood flow was assumed in which the inlet pressure approximated the mean blood pressure (100 mm Hg) and the blood flow velocity was an approximation of the peak systolic flow rate (0.6 m/s). Two sizes of endoluminal grafts were analyzed: the larger graft had an inlet diameter of 3 cm and outlet diameters of 1 cm; the smaller graft diameters measured 2.4 cm proximally and 1.2 cm distally. The endografts were studied in 2 configurations: with the limbs straight and with one bent.

RESULTS

For the larger graft model, the normal peak blood flow induced a downward force of 7 to 9 N on the bifurcated grafts. Bending one of the limbs of the graft produced a sideways force of 1.3 N. For the smaller endograft, the downward force was in the range of 3.1 to 5.1 N and the sideways force on a curved limb was approximately 1.5 N. The magnitude of the forces given by the analytical formulae and the CFD results agreed to within 2 significant figures.

CONCLUSIONS

These results suggest that the downward force on a bifurcated stent-graft, which may exceed the force required to dislodge it when relying on radial attachment alone, is determined mostly by the proximal graft diameter. Curvature of the graft limbs creates an additional sideways force that works to displace the distal limbs of the graft from the iliac arteries.

The C-terminal tail of UNC-60B (actin depolymerizing factor/cofilin) is critical for maintaining its stable association with F-actin and is implicated in the second actin-binding site

Actin depolymerizing factor (ADF)/cofilin changes the twist of actin filaments by binding two longitudinally associated actin subunits. In the absence of an atomic model of the ADF/cofilin-F-actin complex, we have identified residues in ADF/cofilin that are essential for filament binding. Here, we have characterized the C-terminal tail of UNC-60B (a nematode ADF/cofilin isoform) as a novel determinant for its association with F-actin. Removal of the C-terminal isoleucine (Ile152) by carboxypeptidase A or truncation by mutagenesis eliminated F-actin binding activity but strongly enhanced actin depolymerizing activity. Replacement of Ile152 by Ala had a similar but less marked effect; F-actin binding was weakened and depolymerizing activity slightly enhanced. Truncation of both Arg151 and Ile152 or replacement of Arg151 with Ala also abolished F-actin binding and enhanced depolymerizing activity. Loss of F-actin binding in these mutants was accompanied by loss or greatly decreased severing activity. All of the variants of UNC-60B interacted with G-actin in an indistinguishable manner from wild type. Cryoelectron microscopy showed that UNC-60B changed the twist of F-actin to a similar extent to vertebrate ADF/cofilins. Helical reconstruction and structural modeling of UNC-60B-F-actin complex reveal how the C terminus of UNC-60B might be involved in one of the two actin-binding sites.

Disease specific intelligent pre-fetch and hanging protocol for diagnostic neuroradiology workstations

Clinical data sets for neuroradiological cases can be quite large. A typical brain tumor patient at UCLA will undergo 8-10 separate studies over a 2 year period, each study will produce 60-100 magnetic resonance (MR) images. Gathering and sorting through a patient s imaging events during the course of treatment can be both overwhelming and time consuming. The purpose of this research is to develop an intelligent pre-fetch and hanging protocol that automatically gathers the relevant prior examinations from a picture archiving, and communication systems (PACS) archive and sends the pertinent historical images to the diagnostic display station where the new examination is subsequently read out. The intelligent hanging protocol describes the type of layout and sequence for image display. We have developed a classification scheme to organize the pertinent patient information to selectively pre-fetch and intelligently present the images to review brain tumor cases for a diagnostic neuroradiology workstation.

Florid computed tomographic appearance of acute Campylobacter enterocolitis

A 28-year-old male presented with severe abdominal pain and bloody diarrhoea. Computed tomographic scan showed marked swelling of the distal ileum and entire colorectum. The patient recovered and Campylobacter jejuni was subsequently grown from his faeces.

Hormonal regulation and cellular localization of fatty acid synthase in human fetal lung

Fatty acid synthase (FAS; EC 2.3.1.85) supplies de novo fatty acids for pulmonary surfactant synthesis, and FAS gene expression is both developmentally and hormonally regulated in the fetal lung. To further examine hormonal regulation of FAS mRNA and to determine the cellular localization of FAS gene expression, we cultured human fetal lungs (18-22 wk gestation) as explants for 1-4 days in the absence (control) or presence of glucocorticoid [dexamethasone (Dex), 10 nM] and/or cAMP agents (8-bromo-cAMP, 0.1 mM and IBMX, 0.1 mM). FAS protein content and activity increased similarly in the presence of Dex (109 and 83%, respectively) or cAMP (87 and 111%, respectively), and responses were additive in the presence of both hormones (230 and 203%, respectively). With a rabbit anti-rat FAS antibody, FAS immunoreactivity was not detected in preculture lung specimens but appeared in epithelial cells lining the tubules with time in culture. Dex and/or cAMP markedly increased staining of epithelial cells, identified as type II cells, whereas staining of mesenchymal fibroblasts was very low under all conditions. With in situ hybridization, FAS mRNA was found to be enriched in epithelial cells lining the alveolar spaces, and the reaction product increased in these cells when the explants were cultured with the hormones. The increased FAS mRNA content in the presence of Dex and/or cAMP is primarily due to increased stabilization of mRNA, although Dex alone increased the transcription rate by approximately 30%. We conclude that hormonal treatment of cultured human fetal lungs increases FAS gene expression primarily by increasing stability of the message. The induction of FAS during explant culture and by hormones occurs selectively in type II epithelial cells, consistent with the regulatory role of this enzyme in de novo synthesis of fatty acid substrate for surfactant synthesis in perinatal lungs.

MRL-lpr/lpr mice exhibit a defect in maintaining developmental arrest and follicular exclusion of anti-double-stranded DNA B cells

A hallmark of systemic lupus erythematosus and the MRL murine model for lupus is the presence of anti-double-stranded (ds)DNA antibodies (Abs). To identify the steps leading to the production of these Abs in autoimmune mice, we have compared the phenotype and localization of anti-dsDNA B cells in autoimmune (MRL+/+ and lpr/lpr) mice with that in nonautoimmune (BALB/c) mice. Anti-dsDNA B cells are actively regulated in BALB/c mice as indicated by their developmental arrest and accumulation at the T-B interface of the splenic follicle. In the MRL genetic background, anti-dsDNA B cells are no longer developmentally arrested, suggesting an intrinsic B cell defect conferred by MRL background genes. With intact Fas, they continue to exhibit follicular exclusion; however, in the presence of the lpr/lpr mutation, anti-dsDNA B cells are now present in the follicle. Coincident with the altered localization of anti-dsDNA B cells is a follicular infiltration of CD4 T cells. Together, these data suggest that MRL mice are defective in maintaining the developmental arrest of autoreactive B cells and indicate a role for Fas in restricting entry into the follicle.

Characterization of anergic anti-DNA B cells: B cell anergy is a T cell-independent and potentially reversible process

Anti-single stranded DNA (ssDNA) and anti-double stranded DNA (dsDNA) B cells are regulated in non-autoimmune mice. In this report we show that while both anti-ssDNA and anti-dsDNA B cells are blocked in their ability to differentiate into antibody-secreting cells, other phenotypic and functional characteristics distinguish them from one another. Splenic anti-ssDNA B cells are found distributed throughout the B cell follicle, and are phenotypically mature and long-lived. On the other hand, splenic anti-dsDNA B cells are short-lived, exhibit an immature and antigen-experienced phenotype, and localize to the T-B interface of the splenic follicle. Functionally, anti-ssDNA B cells proliferate, albeit suboptimally, in response to anti-IgM, lipopolysaccharide (LPS) and CD40L/IL-4 + anti-IgM stimulation, and tyrosine phosphorylate intracellular proteins upon mIgM cross-linking. Anti-dsDNA B cells, on the other hand, are functionally unresponsive to anti-IgM and LPS stimulation, and do not phosphorylate intracellular proteins, including Syk, upon mIg stimulation. Importantly, anti-DNA B cell anergy is maintained in the absence of T cells since both anti-ssDNA and anti-dsDNA B cells are as efficiently regulated in RAG2(-/-) mice as in their RAG2(+/+) counterparts. Interestingly, the severely anergic state of anti-dsDNA B cells is partially reversible upon stimulation with CD40 ligand and IL-4. In response to these signals, anti-dsDNA B cells remain viable, up-regulate cell surface expression of B7-2 and IgM, and restore their ability to proliferate and phosphorylate Syk upon mIg cross-linking. Collectively, these data suggest that anti-DNA B cell anergy encompasses distinct phenotypes which, even in its most severe form, may be reversible upon stimulation with T cell-derived factors.

[Intestinal parasitic diseases in an urban environment in Sahel. A study in a district of Niamey, Niger]

Health and environment in Niamey, a capital in Sahel, are particularly linked owing to population growth, promiscuity and large pollution induced by human and animal excreta. One district, located in the centre of the town, was surveyed for drinking water quality (ammoniac and bacterial count) and use, as well as for the prevalence of parasites through both a random sample (fixed tools with methiolate-iodine-formaldehyde) and a systematic one (scotch-test). Water consumption was 16.5 litres/day/man from fresh water supplies (87%) and private wells (13%). Ammoniac measures were low in the wells but high in running water (pool and river). It was the same for faecal coliform bacteria. These results give evidence of biotope faecal pollution. The random sample (322 persons, male/female sex ratio 0,85, average age 20,6 years) showed a 42.1% parasitic prevalence. Amoeba was the most frequent parasite (53.6%); and Giardia (14.9%) was the most frequent pathogenic parasite. In the second sample (161 children under 10 years), 24.2% were carriers of oxyuris. This large intestinal parasitism, without any change in connection with previous data in Niger, points to an important fecal contamination of the people more by the way of "dirty hands" than consumption of drinking water. The parasites observed have a short biological cycle, not necessitating long-term maturation in the environment. Those whose ova or larvae must complete their cycle outside have no possibility of surviving in Sahel, thanks to the beneficial effect of sunlight (heat and ultraviolet light). The inhabitants of this district seem to have adapted to intestinal parasitism. But the occurrence of malnutrition linked to a new drought could lead rapidly to a very serious adverse result.

Self-reactive B cells in nonautoimmune and autoimmune mice

The defining feature of autoimmune disease is the presence of specific autoreactive lymphocytes. Systemic lupus erythematosus (SLE), for example, is characterized by a discrete set of antibodies directed to nuclear antigens; these include autoantibodies to DNA and snRNPs that are diagnostic for SLE. The murine model of SLE, the MRL-lpr/lpr mouse, likewise, has a similar autoantibody profile. To understand how SLE-associated autoantibodies are regulated in healthy individuals and to identify mechanisms underlying their expression in autoimmunity, we have developed a transgenic (tg) model system using multiple sets of tgs. The development of B cells bearing these tgs has been studied in BALB/c and MRL-lpr/lpr autoimmune backgrounds, and the relative fates of anti-ssDNA and anti-dsDNA tg B cells when they are a part of a diverse as well as monoclonal B cell repertoire have been evaluated.

Persistence of functionally compromised anti-double-stranded DNA B cells in the periphery of non-autoimmune mice

Both anti-single-stranded (ss) and anti-double-stranded (ds) DNA antibodies are associated with the autoimmune disease systemic lupus erythematosus (SLE), but only anti-dsDNA antibodies are considered one of the diagnostic criteria. Using Ig transgenes coding for anti-DNA we have determined the fate of anti-dsDNA B cells in a non-autoimmune environment. In a Rag-2 wild-type background, B cells expressing the anti-dsDNA Ig transgenes are present in the spleen but dsDNA specificity is disrupted due to expression of endogenous L chains. In a Rag-2-deficient background where co-expression of endogenous Ig is blocked, splenic B cells expressing only the anti-dsDNA transgene Ig are present, indicating that endogenous Ig expression is not required for bone marrow export. The anti-dsDNA B cells that persist are profoundly crippled in that they are unable to proliferate to lipopolysaccharide or anti-Ig stimulation. Furthermore, these anti-dsDNA Ig transgene B cells show a decreased lifespan relative to non-transgene BALB/c B cells. Persistence of anti-dsDNA B cells in the periphery of non-autoimmune mice raises the possibility that their appearance in the context of SLE is due to their reactivation by T cell help.

Regulation of anti-double-stranded DNA B cells in nonautoimmune mice: localization to the T-B interface of the splenic follicle

Systemic lupus erythematosus (SLE) and the MRL-lpr/lpr murine model for SLE are characterized by the presence of serum anti-double-stranded (ds)DNA antibodies (Abs), whereas nonautoimmune individuals have negligible levels of these Abs. To increase the frequency of anti-DNA B cells and identify the mechanisms involved in their regulation in nonautoimmune mice, we have used Ig transgenes (tgs). In the present study, we used the VH3H9 heavy (H) chain tg which expresses an H chain that was repeatedly isolated from anti-dsDNA Abs from MRL-lpr/lpr mice. Because the VH3H9 H chain can pair with endogenous L chains to generate anti-single-stranded DNA, anti-dsDNA, and non-DNA B cells, this allowed us to study the regulation of anti-dsDNA B cells in the context of a diverse B cell repertoire. We have identified anti-dsDNA B cells that are located at the T-B interface in the splenic follicle where they have an increased in vivo turnover rate. These anti-dsDNA B cells exhibit a unique surface phenotype suggesting developmental arrest due to antigen exposure.

Characterization of anti-single-stranded DNA B cells in a non-autoimmune background

Anti-DNA Abs are prevalent in the serum of systemic lupus erythematosus (SLE) patients and in the MRL-lpr/lpr mouse model of SLE, but are generally absent in normal individuals. We have studied the regulation of anti-ssDNA B cells in a non-autoimmune (BALB/c) background by using Ig transgenes (Tgs) encoding anti-DNA Abs. In one case, they are present with other non-DNA-binding B cells (the VH3H9 Tg with endogenous light chains); in the other, they are present as an essentially monospecific population (VH3H9/Vkappa8). We have previously observed that serum anti-ssDNA levels in these Tg mice were no higher than those of non-Tg mice, despite the fact that anti-ssDNA B cells dominate the peripheral B cell repertoire. These results suggested that the anti-ssDNA Tg B cells present are functionally inactivated. In this paper, we isolate B cells from VH3H9/Vkappa8 Tg mice to show that this is indeed the case and go on to further define this state. We demonstrate that VH3H9/Vkappa8 Tg B cells have diminished Ig secretion in response to both T-independent and T-dependent stimuli compared with non-Tg controls. VH3H9/Vkappa8 Tg B cells also show suboptimal proliferation in response to anti-IgM F(ab)'2 fragments and LPS, and are phenotypically distinct in expressing decreased total surface Ig. Despite their functional defects, however, VH3H9/Vkappa8 Tg B cells have an in vivo turnover rate comparable to non-Tg B cells, suggesting that they are long lived.

Characterization of anti-single-stranded DNA B cells in a non-autoimmune background

Anti-DNA Abs are prevalent in the serum of systemic lupus erythematosus (SLE) patients and in the MRL-lpr/lpr mouse model of SLE, but are generally absent in normal individuals. We have studied the regulation of anti-ssDNA B cells in a non-autoimmune (BALB/c) background by using Ig transgenes (Tgs) encoding anti-DNA Abs. In one case, they are present with other non-DNA-binding B cells (the VH3H9 Tg with endogenous light chains); in the other, they are present as an essentially monospecific population (VH3H9/Vkappa8). We have previously observed that serum anti-ssDNA levels in these Tg mice were no higher than those of non-Tg mice, despite the fact that anti-ssDNA B cells dominate the peripheral B cell repertoire. These results suggested that the anti-ssDNA Tg B cells present are functionally inactivated. In this paper, we isolate B cells from VH3H9/Vkappa8 Tg mice to show that this is indeed the case and go on to further define this state. We demonstrate that VH3H9/Vkappa8 Tg B cells have diminished Ig secretion in response to both T-independent and T-dependent stimuli compared with non-Tg controls. VH3H9/Vkappa8 Tg B cells also show suboptimal proliferation in response to anti-IgM F(ab)'2 fragments and LPS, and are phenotypically distinct in expressing decreased total surface Ig. Despite their functional defects, however, VH3H9/Vkappa8 Tg B cells have an in vivo turnover rate comparable to non-Tg B cells, suggesting that they are long lived.

Laparoscopy not recommended for routine appendectomy in men: results of a prospective randomized study

BACKGROUND

Laparoscopic appendectomy has now gained wider acceptance in clinical practice, particularly in the treatment of women with right iliac fossa pain. However, the precise role of laparoscopic appendectomy in men is unclear, and this study was therefore undertaken to examine this specific issue in a prospective randomized trial.

METHODS

One hundred men between the ages of 16 and 65 years who had suspected appendicitis were recruited and randomized to undergo either open or laparoscopic appendectomy. Both groups were compared in terms of their clinical parameters, duration of anesthetic and operation times, postoperative pain, duration of ileus, and length of hospital stay.

RESULTS

The histologic confirmation of appendicitis was present in 94% of the cases for both groups of patients. Laparoscopic appendectomy required significantly longer anesthetic time (72.5 minutes versus 55 minutes) and actual operating time (45 minutes versus 25 minutes) compared with open appendectomy. Postoperative pain as measured by visual analog scale on postoperative days 1 and 2 were not significantly different between the patients who underwent laparoscopic and open surgery with values of 4.7 versus 4.4 and 2.1 versus 2.2, respectively. Also no significant difference was seen between the laparoscopic and open appendectomy groups in the recovery of bowel function (24.7 hours versus 21 hours) and in the length of hospital stay (4.9 days versus 5.3 days).

CONCLUSIONS

The results of this prospective randomized trial showed that there were no significant advantages of laparoscopic appendectomy over open appendectomy for the treatment of male patients with suspected appendicitis. We recommend that the use of laparoscopy be limited to men with atypical pain of uncertain diagnosis and in obese patients.

The induction of immediate early genes in postischemic and transplanted livers in rats. Its relation to organ survival

The protein products of the immediate early genes (IEG)s have been proposed to play an important role in long-term tissue plasticity such as cell repair or programmed cell death. The expression of liver IEGs was studied following liver ischemia (LI) or OLT in rats. In LI, 60 min of warm ischemia was induced in shunted rats (shunt LI group; 100% survival) and nonshunted rats (nonshunted LI group; poor survival). In OLT, donor livers were transplanted into the recipients within 1 hr (fresh liver OLT group; 100% survival) or after 24 hr of storage using University of Wisconsin solution (preserved liver OLT group; poor survival). Using both models, IEG mRNAs (c-fos and c-jun) were analyzed by Northern blot hybridization at various times before and after reperfusion. The expression of liver IEGs was not induced by warm ischemia and cold preservation alone. Reperfusion of livers following warm ischemia or cold preservation resulted in a distinctly different pattern of gene expression in viable and nonviable livers. In shunted LI and fresh liver OLT groups (viable), c-fos and c-jun mRNAs increased markedly to a peak value within 1-2 hr of reperfusion, returning to basal level by 3 hr. In nonviable livers, the level of these mRNAs was detected continuously at 3 hr of reperfusion in the nonshunted LI model and also at 6 hr after reperfusion in the preserved liver OLT group. Our data suggest that a protracted pattern of expression of c-fos and c-jun in the liver at the early stage of reperfusion might be correlated with the severity of liver transplant-related insults and subsequent graft failure.

cDNA cloning of a mouse mammary epithelial cell surface protein reveals the existence of epidermal growth factor-like domains linked to factor VIII-like sequences

A 2.1-kilobase cDNA coding for a surface protein of mammary epithelial cells has been isolated from a mouse mammary gland lambda gt11 cDNA library. Sequence analysis of this cDNA reveals an open reading frame of 1389 base pairs that defines a protein with a molecular mass of 51.5 kDa. Structural analysis of the predicted sequence identifies two putative functional domains of the protein: (i) an N-terminal cysteine-rich region that is similar to epidermal growth factor-like domains of Drosophila Notch-1 protein and (ii) a large segment of the sequence that exhibited 54.5% identity with C-terminal domains of human coagulation factors VIII and V. These similarities in structure are used to predict the possible functions of the protein and its means of interaction with the cell surface. mRNA expression was detectable in mammary tissue from nonpregnant animals but was maximal in the lactating gland. In cultured cells, mRNA levels also correlated with the degree of cellular differentiation.

Generalized peritonitis due to spontaneous rupture of pyometra

Spontaneous rupture of pyometra is a rare cause of generalized peritonitis. Only a few cases have been recorded in the English medical literature, most of which were associated with gynaecological malignancy. We have recently treated a patient with generalized peritonitis due to ruptured pyometra, in which there was no evidence of malignancy or other cervical disease. From comparison with the other published case reports, several features deserve emphasis.

Group therapy with Southeast Asian refugees

This report describes a one-year experience with a new program of group therapy for Southeast Asians who were treated in a psychiatric program for Indochinese refugees. Cultural factors involving communication styles, respect for authority, and traditional social relationships greatly influence the group process. Socialization experiences which encouraged traditional activities and practical information were the most acceptable medium by all the groups. Psychological issues of losses, cultural conflicts, and persistent discussion of somatic symptoms were voiced throughout the activities. Formal group psychotherapy was periodically useful in some groups. Flexibility, meeting concrete needs, keeping a bicultural focus, and maintaining the individual therapy sessions contributed to the acceptance by the patient.

Electrets for use as dosimeters in radiography

A compact device for the manufacturing of electrets and for the measurement of the dose to the skin of the patient in radiography has been developed and described. The surface potential of a polarized polymer electret decreases when it is exposed to radiation. The measurement of the variation in surface potential appears to be a reliable method for the evaluation of the dose. The electret does not disturb the examination nor the radiographic image as it can be given tissue equivalent properties.