Initial Experience and Clinical Assessment of the Karl Storz FLEX-XC1 Single-Use Flexible Ureteroscope

INTRODUCTION

The Karl Storz FLEX-XC1 is a novel single-use flexible ureteroscope that uses the same videographics platform as its reusable digital counterpart. We evaluated the technical performance of the FLEX-XC1 in its initial clinical use.

METHODS

We reviewed a series of consecutive ureteroscopy procedures performed by 2 endourologists using the FLEX-XC1 for indications for which we typically use a single-use device: total stone burden > 15 mm or > 10 mm in the lower pole, anticipated case duration > 60 minutes, bilateral procedure, or upper tract urothelial cancer procedures. We assessed device tip deflection, intraoperative mechanical failure, and clinical outcomes for each case. Surgeons rated visual clarity, image quality, and maneuverability on a 1 to 5 Likert scale.

RESULTS

Of 29 procedures using FLEX-XC1, 27 (93%) were successfully completed. Preoperative upward deflection was < 270° in 6 (21%) cases, and downward deflection was < 270° in 9 (31%) cases. Three types of intraoperative malfunctions occurred: rotational twisting of deflectable tip (4 cases, 13%), device not advancing through distal ureter (1 case, 3%), and working channel not accommodating a 365-μm laser (1 case, 3%). Visual clarity, image quality, and maneuverability were rated as 5 "very good" or 4 "good" in 100%, 100%, and 97% of cases, respectively. No device-specific or general 30-day complications were observed.

CONCLUSIONS

The FLEX-XC1 showed comparable image quality and maneuverability to reusable digital devices. We observed incomplete deflection in up to 31% of cases and mechanical failure in 2 cases. The FLEX-XC1 may be advantageous in prolonged cases where maintaining visual clarity is paramount.

Intraureteral indocyanine green augments ureteral identification and avoidance during complex robotic-assisted colorectal surgery

AIM

Up to 10% of patients who undergo nonurological abdominopelvic operations suffer a ureteral injury. While preoperative ureteral stenting to facilitate identification of the ureter is common, it does not reduce the incidence of intraoperative ureteral injury and is not without risk. As we continue to broaden the application of minimally invasive surgical techniques, a new form of ureteral identification and avoidance that does not rely on tactile feedback is needed. We report our initial experience with intraureteral indocyanine green (ICG) for ureteral identification and avoidance during complex robotic-assisted colorectal surgery.

METHOD

Patients undergoing adjunctive ureteral identification during robotic-assisted colorectal surgery were prospectively identified. Each patient underwent intraureteral ICG administration using rigid cystoscopy (22 Fr). A 5-Fr open-ended ureteral catheter was inserted up to 20 cm and used to inject 5 ml of 2.5 mg/ml ICG as the catheter was withdrawn to the ureteral orifice. Intraureteral ICG was then detected using near-infrared laser fluorescence technology (Firefly®).

RESULTS

Successful ICG-enhanced ureteral identification and avoidance was performed in 15 of 16 (94%) patients undergoing robotic-assisted colorectal surgery. The median ICG instillation time was 11.5 min (range 4-21 min) and the median operative time with ICG visualization was 489 min (8 h 9 min) [range 268-738 min (4 h 28 min-12 h 18 min)]. No patient experienced intraoperative ureteral injury and there were no adverse sequelae or complications associated with intraureteral ICG administration.

CONCLUSION

Intraureteral ICG is a safe and effective method of intraoperative ureteral identification and avoidance during complex robotic-assisted colorectal surgery. Precise and prolonged ureteral visualization was achieved, allowing for long operative times compatible with complex robotic-assisted operations.

Comparing and Contrasting Peyronie's Disease Guidelines: Points of Consensus and Deviation

BACKGROUND

Peyronie's disease (PD) is a challenging clinical entity. To assist clinicians with diagnosis and management, four separate organizations have published PD guidelines over the past five years, but there remains a lack of consensus and data-driven recommendations for many aspects of diagnosis and treatment.

AIM

To compare and contrast PD guidelines, highlighting key similarities and differences among the guideline panel recommendations and identify areas for further research.

METHODS

We performed an extensive review to compare and contrast diagnosis and treatment recommendations from publically available published PD guidelines from four different organizations: American Urological Association, European Association of Urology, Canadian Urologic Association, and the International Society of Sexual Medicine.

OUTCOMES

Key similarities and differences with regards to definition, evaluation, nonsurgical and surgical treatments were compared.

RESULTS

Points of general consensus among the guideline panels included: History is adequate for diagnosis of PD, and intracavernosal injection is a gold standard to evaluate penile deformity prior to invasive intervention. Careful counseling with shared decision-making is required prior to treatment. In general, plication and incision and/or grafting surgery is reserved for patients with preserved erectile function whereas penile prosthesis implantation is the only surgical option for PD patients with erectile dysfunction. Overall, nonsurgical treatments have inferior evidence of efficacy with these being the main area of controversy; however, all societies recognize that intralesional injections may be used. 0Further research into the pathophysiology of PD may direct novel treatments targeted towards early intervention and rigorous outcomes research may direct best practices for the surgical treatment of PD in the future.

CLINICAL IMPLICATIONS

PD is a challenging clinical entity. Direct comparison of the published PD guidelines highlights clear standards of care as well as areas where more research is needed to promote higher levels of evidence-based practice.

STRENGTHS & LIMITATIONS

To our knowledge this is the first report to directly compare and contrast published guidelines pertaining to the diagnosis and management of PD. Limitations include the lack of evidence-quality review pertaining to individual guideline recommendations, although this was not the aim of this review.

CONCLUSION

We highlight consensus of major urologic societies on many aspects of work up and management of PD with notable exceptions which may guide further research. Manka MG, White LA, Yafi FA, et al. Comparing and Contrasting Peyronie's Disease Guidelines: Points of Consensus and Deviation. J Sex Med 2021;18:363-375.

Robotic-assisted bladder neck procedures in children with neurogenic bladder

PURPOSE

To review the current status of robotic-assisted laparoscopic surgical techniques for bladder neck procedures in children with incontinence secondary to neurogenic bladder.

METHODS

A comprehensive review of the literature on robotic-assisted bladder neck procedures was conducted, with a focus on articles published in the last 25 years. These data were subsequently compared to published series of open bladder neck procedures and published results from robotic-assisted bladder neck reconstruction series completed at our institution.

RESULTS

The principle bladder neck procedures for incontinence in pediatric patients with neurogenic bladder include: Artificial Urinary Sphincter, Bladder Neck Sling, Bladder Neck Closure, and Bladder Neck Reconstruction. Continence rates range from 60 to 100% with a lack of expert consensus on the preferred procedure (or combination of procedures). Robotic-assisted approaches are associated with longer operative times, especially early in the surgical experience, but demonstrate equivalent continence rates with potential benefits including low interoperative blood loss, improved cosmesis, and decreased intra-abdominal adhesion formation.

CONCLUSIONS

Robotic-assisted procedures of the bladder neck are safe, feasible, follow the same steps and principles as those of open surgery and produce equivalent continence rates. Robotic-assisted techniques can be adapted to a variety of bladder neck procedures and safely expanded to selected patients with the previous open abdominal surgery.

Robotic-Assisted Bladder Neck Procedures for Incontinence in Pediatric Patients

Purpose: To review the current status of bladder neck procedures for incontinence in pediatric patients, focusing on the increasing role of robotic-assisted laparoscopic surgical techniques. Methods: A comprehensive review of the literature on open and robotic-assisted bladder neck procedures was conducted, with a focus on articles published in the last 20 years. This data was subsequently compared with published results from robotic-assisted bladder neck reconstruction series completed at our institution. Results: The principal bladder neck procedures for incontinence in pediatric patients include: Artificial Urinary Sphincter, Bladder Neck Sling, Bladder Neck Closure and Bladder Neck Reconstruction. Continence rates range from 60 to 100% with a lack of expert consensus on the preferred procedure (or combination of procedures). Robotic-assisted approaches are associated with longer operative times, especially early in the surgical experience, but demonstrate equivalent continence rates with potential benefits including: low intraoperative blood loss, improved cosmesis, and decreased intra-abdominal adhesion formation. Conclusions: Robotic-assisted procedures of the bladder neck are safe, feasible, follow the same steps and principles as those of open surgery and produce equivalent continence rates. Robotic-assisted techniques can be adapted to a variety of bladder neck procedures and safely expanded to selected patients with previous open abdominal surgery.

Influenza A virus in swine breeding herds: Combination of vaccination and biosecurity practices can reduce likelihood of endemic piglet reservoir

Recent modelling and empirical work on influenza A virus (IAV) suggests that piglets play an important role as an endemic reservoir. The objective of this study is to test intervention strategies aimed at reducing the incidence of IAV in piglets and ideally, preventing piglets from becoming exposed in the first place. These interventions include biosecurity measures, vaccination, and management options that swine producers may employ individually or jointly to control IAV in their herds. We have developed a stochastic Susceptible-Exposed-Infectious-Recovered-Vaccinated (SEIRV) model that reflects the spatial organization of a standard breeding herd and accounts for the different production classes of pigs therein. Notably, this model allows for loss of immunity for vaccinated and recovered animals, and for vaccinated animals to have different latency and infectious periods from unvaccinated animals as suggested by the literature. The interventions tested include: (1) varied timing of gilt introductions to the breeding herd, (2) gilt separation (no indirect transmission to or from the gilt development unit), (3) gilt vaccination upon arrival to the farm, (4) early weaning, and (5) vaccination strategies of sows with different timing (mass and pre-farrow) and efficacy (homologous vs. heterologous). We conducted a Latin Hypercube Sampling and Partial Rank Correlation Coefficient (LHS-PRCC) analysis combined with a random forest analysis to assess the relative importance of each epidemiological parameter in determining epidemic outcomes. In concert, mass vaccination, early weaning of piglets (removal 0-7days after birth), gilt separation, gilt vaccination, and longer periods between introductions of gilts (6 months) were the most effective at reducing prevalence. Endemic prevalence overall was reduced by 51% relative to the null case; endemic prevalence in piglets was reduced by 74%; and IAV was eliminated completely from the herd in 23% of all simulations. Importantly, elimination of IAV was most likely to occur within the first few days of an epidemic. The latency period, infectious period, duration of immunity, and transmission rate for piglets with maternal immunity had the highest correlation with three separate measures of IAV prevalence; therefore, these are parameters that warrant increased attention for obtaining empirical estimates. Our findings support other studies suggesting that piglets play a key role in maintaining IAV in breeding herds. We recommend biosecurity measures in combination with targeted homologous vaccination or vaccines that provide wider cross-protective immunity to prevent incursions of virus to the farm and subsequent establishment of an infected piglet reservoir.

Global epidemiology of amyotrophic lateral sclerosis: a systematic review of the published literature

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is relatively rare, yet the economic and social burden is substantial. Having accurate incidence and prevalence estimates would facilitate efficient allocation of healthcare resources.

OBJECTIVE

To provide a comprehensive and critical review of the epidemiological literature on ALS.

METHODS

MEDLINE and EMBASE (1995-2011) databases of population-based studies on ALS incidence and prevalence reporting quantitative data were analyzed. Data extracted included study location and time, design and data sources, case ascertainment methods and incidence and/or prevalence rates. Medians and interquartile ranges (IQRs) were calculated, and ALS case estimates were derived using 2010 population estimates.

RESULTS

In all, 37 articles met the inclusion criteria. In Europe, the median incidence rate (/100,000 population) was 2.08 (IQR 1.47-2.43), corresponding to an estimated 15,355 (10,852-17,938) cases. Median prevalence (/100,000 population) was 5.40 (IQR 4.06-7.89), or 39,863 (29,971-58,244) prevalent cases.

CONCLUSIONS

Disparity in rates among ALS incidence and prevalence studies may be due to differences in study design or true variations in population demographics such as age and geography, including environmental factors and genetic predisposition. Additional large-scale studies that use standardized case ascertainment methods are needed to more accurately assess the true global burden of ALS.

Factors associated with failure to correct the international normalised ratio following fresh frozen plasma administration among patients treated for warfarin-related major bleeding. An analysis of electronic health records

This study assessed the frequency and factors associated with failure to correct international normalised ratio (INR) in patients administered fresh frozen plasma (FFP) for warfarin-related major bleeding. This retrospective database analysis used electronic health records from an integrated health system. Patients who received FFP between 01/01/2004 and 01/31/2010, and who met the following criteria were selected: major haemorrhage diagnosis the day before to the day after initial FFP administration; INR ≥2 on the day before or the day of FFP and another INR result available; warfarin prescription within 90 days. INR correction (defined as INR ≤1.3) was evaluated at the last available test up to one day following FFP. A total of 414 patients met selection criteria (mean age 75 years, 53% male, mean Charlson score 2.5). Patients presented with gastrointestinal bleeding (58%), intracranial haemorrhage (38%) and other bleed types (4%). The INR of 67% of patients remained uncorrected at the last available test up to one day following receipt of FFP. In logistic regression analysis, the INR of patients who were older, those with a Charlson score of 4 or greater, and those with non-ICH bleeds (odds ratio vs. intracranial bleeding 0.48; 95% confidence interval 0.31-0.76) were more likely to remain uncorrected within one day following FFP administration. In an alternative definition of correction, (INR ≤1.5), 39% of patients' INRs remained uncorrected. For a substantial proportion of patients, the INRs remain inadequately or uncorrected following FFP administration, with estimates varying depending on the INR threshold used.

Sensitive rapid detection method for viable bacterial cells

A rapid sensitive method for the detection of viable bacterial cells is described in which P as inorganic orthophosphate is used to label the cells. Factors affecting the uptake of P by cells as well as the sensitivity of the method have been explored with suspensions of Aerobacter aerogenes. The uptake of PO(4) is dependent on several factors. Of various incubation media tested, one composed of 0.005 m KCl, 0.002 m MgSO(4) and 10 mg/ml of glucose was found to best stimulate the uptake of the tracer. Incubation time and temperature and level of isotope and of unlabeled P also affected uptake. Labeled cells were collected on a membrane filter for measurement of radioactivity. Under optimal conditions, as few as 23 viable cells per milliliter were detected in 1 hr with 95% confidence.

The aryl hydrocarbon receptor (AhR) pathway as a regulatory pathway for cell adhesion and matrix metabolism

The aryl hydrocarbon receptor (AhR) is an orphan receptor in the basic helix-loop-helix PAS family of transcriptional regulators. Although the endogenous regulator of this pathway has not been identified, the AhR is known to bind and be activated by a variety of compounds ranging from environmental contaminants to flavanoids. The function of this receptor is still unclear; however, animal models indicate that the AhR is important for normal development. One hypothesis is that the AhR senses cellular stress and initiates the cellular response by altering gene expression and inhibiting cell cycle progression and that activation of the AhR by exogenous environmental chemicals results in the dysregulation of this normal function. In this review we will examine the role of the AhR in the regulation of genes and proteins involved in cell adhesion and matrix remodeling, and discuss the implications of these changes in development and disease. In addition, we will discuss evidence suggesting that the AhR pathway is responsive to changes in matrix composition as well as cell-cell and cell-matrix interactions.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure of normal human dermal fibroblasts results in AhR-dependent and -independent changes in gene expression

Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) results in a variety of lesions in mammals including severe skin lesions. The majority of TCDD's biological effects are mediated through activation of the aryl hydrocarbon receptor (AhR). We have chosen to examine the effect of TCDD and the AhR pathway on dermal fibroblasts because this cell type plays an integral role in skin homeostasis through the production of cytokines and other factors that regulate epidermal proliferation and differentiation. Our data show that normal human dermal fibroblasts (NHDFs) are responsive to TCDD, as demonstrated by induction of cytochrome p450 1B1 (CYP1B1) expression. Further, our data demonstrate that TCDD treatment of NHDFs results in significant (75-90%) decrease in expression of Id-1 and Id-3, proteins that are involved in regulation of cell proliferation and differentiation. The Id (Inhibitor of DNA binding) proteins are transcriptional inhibitors that function by forming inactive heterodimers with other HLH proteins. TCDD-repression of Id-1 and -3 is independent of de novo protein synthesis; co-treatment with cycloheximide has no effect on TCDD inhibition of Id-1 and Id-3. Co-treatment with the AhR antagonist alpha-naphthoflavone also does not block inhibition of Id-1 and Id-3 by TCDD, suggesting that TCDD inhibition of Id-1 and Id-3 is, at least in part, mediated independently of the AhR pathway. Our data also show that TCDD inhibits expression of the cell cycle regulatory gene p16(ink4a), which is often linked to Id expression. TCDD-induced reduction of p16(ink4a) expression is also independent of protein synthesis and the AhR pathway.

Larval zebrafish as a model for glucose metabolism: expression of phosphoenolpyruvate carboxykinase as a marker for exposure to anti-diabetic compounds

The zebrafish model system is one of the most widely used animal models for developmental research and it is now becoming an attractive model for drug discovery and toxicological screening. The completion of sequencing the zebrafish genome and the availability of full-length cDNAs and DNA microarrays for expression analysis, in addition to techniques for generating transgenic lines and targeted mutations, have made the zebrafish model even more attractive to researchers. Recent data indicate that the regulation of glucose metabolism in zebrafish, through the production of insulin, is similar to mammalian models, and many of the genes involved in regulating blood glucose levels have been identified in zebrafish. The data presented here show that adult zebrafish respond to anti-diabetic drugs similarly to mammalian models, by reducing blood glucose levels. Furthermore, we show that the expression of phosphoenolpyruvate carboxykinase (PEPCK), which catalyzes a rate-limiting step in gluconeogenesis and is transcriptionally regulated by glucagon and insulin, is regulated in larval zebrafish similarly to that seen in mammalian systems, and changes in PEPCK expression can be obtained through real-time PCR analysis of whole larval RNA. Taken together, these data suggest that larval zebrafish may be an appropriate model for the examination of glucose metabolism, using PEPCK as an indicator of blood glucose levels.

Expression of the helix–loop–helix protein inhibitor of DNA binding-1 (ID-1) is activated by all-trans retinoic acid in normal human keratinocytes

The ID (inhibitor of differentiation or DNA binding) helix-loop-helix proteins are important mediators of cellular differentiation and proliferation in a variety of cell types through regulation of gene expression. Overexpression of the ID proteins in normal human keratinocytes results in extension of culture lifespan, indicating that these proteins are important for epidermal differentiation. Our hypothesis is that the ID proteins are targets of the retinoic acid signaling pathway in keratinocytes. Retinoids, vitamin A analogues, are powerful regulators of cell growth and differentiation and are widely used in the prevention and treatment of a variety of cancers in humans. Furthermore, retinoic acid is necessary for the maintenance of epithelial differentiation and demonstrates an inhibitory action on skin carcinogenesis. We examined the effect of all-trans retinoic acid on expression of ID-1, -2, -3, and -4 in normal human keratinocytes and found that exposure of these cells to all-trans retinoic acid causes an increase in both ID-1 and ID-3 gene expression. Furthermore, our data show that this increase is mediated by increased transcription involving several cis-acting elements in the distal portion of the promoter, including a CREB-binding site, an Egr1 element, and an YY1 site. These data demonstrate that the ID proteins are direct targets of the retinoic acid signaling pathway. Given the importance of the ID proteins to epidermal differentiation, these results suggest that IDs may be mediating some of the effects of all-trans retinoic acid in normal human keratinocytes.

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces matrix metalloproteinase (MMP) expression and invasion in A2058 melanoma cells

There has been a 34% increase in melanoma related mortality in the United States from 1973 to 1992. Although few successful treatments for malignant melanoma exist, it is known that genetic susceptibility and environmental factors contribute to the initiation and progression of melanoma. Excessive UV exposure is considered the main etiological factor in melanoma initiation, however, epidemiological and experimental evidence suggests that exposure to environmental carcinogens contribute to melanoma. We propose that exposure to environmental chemicals that activate the aryl hydrocarbon receptor pathway contribute to melanoma progression, specifically through stimulation of the expression and activity of the matrix metalloproteinases (MMPs). Therefore, we investigated the effect of AhR activation on normal human melanocytes and several melanoma cell lines. The data presented here demonstrate that normal melanocytes and melanoma cells express the AhR and Arnt and are responsive to activation by TCDD. Furthermore, activation of this pathway in transformed melanoma cells (A2058) results in increased expression and activity of MMP-1, MMP-2 and MMP-9, as well as increased invasion using in vitro invasion assays. Furthermore, TCDD-induced expression of the MMP-1 promoter in melanoma cells appears to require different elements than those required in untransformed cells, indicating that this pathway may have multiple mechanisms for activation of MMP expression.

Genotyping of Serratia marcescens Strains Associated with Cucurbit Yellow Vine Disease by Repetitive Elements-Based Polymerase Chain Reaction and DNA-DNA Hybridization

ABSTRACT The bacterium that causes cucurbit yellow vine disease (CYVD) has been placed in the species Serratia marcescens based on 16S rDNA and groE sequence analysis. However, phenotypic comparison of the organism with S. marcescens strains isolated from a variety of ecological niches showed significant heterogeneity. In this study, we compared the genomic DNA of S. marcescens strains from different niches as well as type strains of other Serratia spp. through repetitive elements-based polymerase chain reaction (rep-PCR) and DNA-DNA hybridization. With the former, CYVD strains showed identical banding patterns despite the fact that they were from different cucurbit hosts, geographic locations, and years of isolation. In the phylogenetic trees generated from rep-PCR banding patterns, CYVD strains clearly were differentiated from other strains but formed a loosely related group with S. marcescens strains from other niches. The homogeneity of CYVD strains was supported further by the DNA relatedness study, in that labeled DNA from the cantaloupe isolate, C01-A, showed an average relative binding ratio (RBR) of 99%, and 0.33% divergence to other CYVD strains. Used as a representative strain of CYVD, the labeled C01-A had a RBR of 76%, and a 4.5% divergence to the S. marcescens type strain. These data confirm the previous placement of CYVD strains in S. marcescens. Our investigations, including rep-PCR, DNA-DNA hybridization, and previous phenotyping experiments, have demonstrated that CYVD-associated strains of S. marcescens cluster together in a group significantly different from other strains of the species.

Written information about epidural analgesia for women in labour: Did it improve knowledge?

There is evidence that despite a distressed appearance, women in labour should be informed about the side effects and risks associated with epidural analgesia. An audit of 100 women who had used epidural analgesia for labour in our hospital and who had received a verbal explanation of the benefits, risks and side effects of epidural analgesia showed that the level of knowledge was low. An A5 laminated epidural information card was prepared summarising this information. The midwife and the anaesthetist used the card during labour as a focus for verbal discussion and as written reinforcement for the woman and her partner. A repeat audit of a further 100 women showed a statistically significant improvement in the level of knowledge about epidural analgesia. This audit suggests that the use of a written information card is beneficial. It improves and reinforces the process of giving information thus assisting the consent process.

Brewers dried yeast as a source of mannan oligosaccharides for weanling pigs

Brewers dried yeast, a source of mannan oligosaccharides (MOS), was assessed as an alternative to an antimicrobial agent (carbadox) for young pigs in two experiments. The yeast contained 5.2% MOS. Agglutination tests confirmed adsorption of several serovars of E. coli and Salmonella spp. onto the yeast product. In Exp. 1, seven replicates (five pigs per pen) of 22-d-old pigs were fed a nonmedicated basal diet or the basal diet with carbadox (55 mg/kg), yeast (3%), or a combination of 3% yeast and 2% citric acid for 28 d. Carbadox did not improve growth performance. Growth rate and feed intake were depressed (P < 0.05) in pigs fed yeast alone or in combination with acid. Log counts of total coliforms, Escherichia coli, and Clostridium perfringens in feces were not affected by diet, but Bifidobacteria spp. counts were lower (P < 0.05) in pigs fed the yeast + acid diet and lactobacilli counts were higher (P < 0.05) in pigs fed yeast. Fecal pH and VFA concentrations and intestinal morphological traits were not consistently affected by diet. Serum IgG levels were elevated in the yeast + acid (P < 0.01) group. In Exp. 2, the effects of yeast and carbadox additions to the diet on enteric microbial populations in young pigs housed in isolation units were evaluated. Pigs (n = 24) were weaned at 11 d of age (4.1 kg BW) and placed in isolation chambers (two pigs per chamber) equipped with individual air filtering systems and excrement containers. Treatments were a nonmedicated basal diet and the basal diet with 55 mg/kg of carbadox or with 3% yeast. Diets were fed for 29 d, then each pig was orally dosed with approximately 9.5 x 10(8) CFU of E. coli K88. Daily fecal E. coli K88 counts were not different (P > 0.05) among treatments, but fecal shedding of carbadox-resistant coliforms was higher (P < 0.01) during the 9-d period in pigs fed carbadox. Total fecal coliforms were consistently lower throughout the postinoculation period in pigs fed yeast (P < 0.05). Yeast reduced colonization oftotal coliforms in the duodenum,jejunum, cecum, and colon, but it did not have a consistent effect on colonization of E. coli K88. Pigs fed yeast tended (P < 0.10) to have higher serum IgG levels than controls. In these experiments, brewers dried yeast and carbadox had minimal effects on growth, microbial populations, and intestinal health traits of early-weaned pigs, but certain serum immunological traits were enhanced by feeding yeast.

Patient-controlled analgesia and postoperative nausea and vomiting: efficacy of a continuous infusion of ondansetron

A continuous infusion of ondansetron was compared with a placebo infusion in 80 patients undergoing major breast reconstructive surgery. All patients received a standard anaesthetic and a bolus dose of ondansetron after induction. They were then randomly allocated to receive an intravenous infusion of ondansetron or a placebo infusion for 24 h in a double-blind fashion. Postoperative analgesia was provided by patient-controlled subcutaneous diamorphine. In the ondansetron group, the severity of nausea, measured by a 10-point verbal rating scale, was reduced (p = 0.01) and fewer patients stated at postoperative interview that nausea and vomiting was a problem (p = 0.01).

Infusional CHOP chemotherapy (CVAD) with or without chemosensitizers offers no advantage over standard CHOP therapy in the treatment of lymphoma: a Southwest Oncology Group Study

PURPOSE

Two phase II studies were conducted to evaluate infusional cyclophosphamide, doxorubicin, vincristine, and dexamethasone chemotherapy, termed the CVAD regimen, alone (Southwest Oncology Group [SWOG] 9240) and with the chemosensitizers verapamil and quinine (SWOG 9125) to assess effects on response, survival, and toxicity in intermediate- and high-grade advanced-stage non-Hodgkin's lymphoma (NHL). The results were compared with the historic group of patients randomized to CHOP chemotherapy on Intergroup (INT) 0067 (SWOG 8516).

PATIENTS AND METHODS

All patients had biopsy-proven intermediate- or high-grade NHL (lymphoblastic histology excluded), were ambulatory and previously untreated, and had bulky stage II, III, or IV disease. One hundred twelve patients were registered on SWOG 9240 and received cyclophosphamide 750 mg/m(2) by intravenous bolus day 1, doxorubicin 12.5 mg/m(2)/d and vincristine 0.5 mg/d delivered as a continuous 96-hour infusion on days 1 through 4, and dexamethasone 40 mg/d orally on days 1 through 4 (CVAD). Cycles were repeated every 21 days for eight cycles. One hundred patients on SWOG 9125 received the same chemotherapy and the chemosensitizers verapamil 240 mg bid and quinine 40 mg tid. Chemosensitizers were begun 24 hours before chemotherapy and continued for a total of 6 days.

RESULTS

Eighty-one patients were eligible for each study. The complete response (CR) rates were 39% on SWOG 9125 and 31% on SWOG 9240. With a median follow-up of 5.8 years on SWOG 9125 and 4.5 years on SWOG 9240, the 2-year failure-free survival (FFS) rate was 42% on SWOG 9125 and 41% on SWOG 9240. Two-year overall survival (OS) rate was 64% on SWOG 9125 and 58% on SWOG 9240. These results are comparable to a 44% CR rate, a 2-year FFS of 46%, and 2-year OS of 63% observed in 225 patients treated with CHOP on INT 0067 (SWOG 8516).

CONCLUSION

CVAD combination chemotherapy alone or with the chemosensitizers verapamil and quinine is not promising therapy with respect to improved response or OS in intermediate- and high-grade advanced-stage NHL.

Technology meets healthcare: distance learning and telehealth

In a time of increasing demands on physician productivity, computer and communication technologies allow health professionals to experiment with many applications that may provide opportunities to meet clinical demands while still participating in educational and research activities. "Telehealth" is a comprehensive term for the support of long distance clinical healthcare, patient and professional health-related education, public health, and health administration. Educational opportunities are growing exponentially for those who cannot attend traditional courses because of limited time or geographic considerations. Research and medical information and medical consultations are being delivered instantly across wide geographic areas. Nearly every federal agency has a web site providing health information. Integrated clinical management systems can facilitate the management of patients with chronic diseases and provide an efficient way to integrate consultations and patient education, monitoring, follow-up, and support. Administrative functions can be interfaced with clinical management providing practitioners with the ability to better organize their services. Information systems at all levels are expanding their capacities and capabilities to meet the growing demand for medical knowledge.

Growth state-dependent binding of USF-1 to a proximal promoter E box element in the rat plasminogen activator inhibitor type 1 gene

Induced PAI-1 gene expression in renal epithelial (NRK-52E, clone EC-1) cells occurs as part of the immediate-early response to serum. PAI-1 transcripts are maximally expressed early in G(1) (within 4 h of serum addition to quiescent EC-1 cells) and then subsequently decline to basal levels prior to entry into DNA synthetic phase. Comparative analysis of PAI-1 mRNA abundance and de novo-synthesized thiolated RNA in quiescent cells, as well as at 4 h (early G(1)) and 20 h (late G(2)) postserum addition, in conjunction with RNA decay measurements indicated that PAI-1 gene regulation upon growth activation was predominantly transcriptional. An E box motif (CACGTG), important in the induced expression of some growth state-dependent genes, mapped to nucleotides -160 to -165 upstream of the transcription start site in the PAI-1 proximal promoter. Mobility-shift assessments, using a 18-bp deoxyoligonucleotide construct containing the E box within the context of PAI-1-specific flanking sequences, confirmed binding of EC-1 nuclear protein(s) to this probe and, specifically, to the E box hexanucleotide site. The specificity of this protein-probe interaction was verified by competition analyses with double-stranded DNA constructs that included E box deoxyoligonucleotides with non-PAI-1 flanking bases, mutant E box sequences incapable of binding NRK nuclear proteins, and unrelated (i.e., AP-1) target motifs. Extract immunodepletion and supershift/complex-blocking experiments identified one PAI-1 E box-binding protein to be upstream stimulatory factor-1 (USF-1), a member of the HLH family of transcription factors. Mutation of the CACGTG site to TCCGTG in an 18-bp PAI-1 probe inhibited the formation of USF-1-containing complexes confirming that an intact E box motif at -160 to -165 bp in the PAI-1 promoter and, in particular, the CA residues at -165 and -164 are essential for USF-1 binding. Incorporation of this 2 bp change into a reporter construct containing 764 bp of the proximal PAI-1 "promoter" ligated to a CAT gene effectively reduced (by 74%) CAT activity in cycling cells. An intact E box motif at nucleotides -160 to -165 in the PAI-1 promoter, thus, is an important functional element in the regulation of PAI-1 transcriptional activity in renal cells.

Transforming growth factor beta inhibitory element in the rabbit matrix metalloproteinase-1 (collagenase-1) gene functions as a repressor of constitutive transcription

Transforming growth factor beta (TGF-beta) is a potent modulator of the extracellular matrix, enhancing collagen synthesis and regulating expression of several genes that encode the matrix metalloproteinases (MMPs), enzymes that degrade the extracellular matrix. In this study, we explored the mechanisms whereby TGF-beta inhibits expression of the MMP-1 (collagenase 1) gene. We used transient transfection and gel mobility shift assays to characterize a TGF beta inhibitory element (TIE) at -249 bp in the rabbit MMP-1 promoter, which is also conserved at -246 bp in the human gene. This sequence shares homology to a previously identified TIE in the rat stromelysin-1 (MMP-3) promoter, where it is located at -709 bp. Mutational analyses and transient transfections indicate that MMP-1 TIE functions both as a constitutive repressor of MMP-1 gene expression and, in the presence of TGF-beta, as an antagonist of transcriptional induction by phorbol esters. c-Fos binds to the TIE in the rabbit MMP-1 promoter, along with other nuclear proteins, even in the absence of treatment with TGF-beta. However, the pattern of proteins binding to the TIE is altered in the presence of nuclear extracts from TGF-beta-treated cells, suggesting that TGF-beta leads to an alteration in protein/DNA interaction, with subsequent modulation of MMP-1 gene expression. We conclude that in the rabbit MMP-1 promoter, the TIE has dual functions as a repressor of basal transcription and as a mediator of the biologic effects of TGF-beta. Furthermore, these dual functions provide additional and subtle mechanisms for regulating MMP-1 gene expression under a variety of biological and pathological conditions.

Induction of Eph B3 after spinal cord injury

Spinal cord injury (SCI) in adult rats initiates a cascade of events producing a nonpermissive environment for axonal regeneration. This nonfavorable environment could be due to the expression of repulsive factors. The Eph receptor protein tyrosine kinases and their respective ligands (ephrins) are families of molecules that play a major role in axonal pathfinding and target recognition during central nervous system (CNS) development. Their mechanism of action is mediated by repellent forces between receptor and ligand. The possible role that these molecules play after CNS trauma is unknown. We hypothesized that an increase in the expression of Eph proteins and/or ephrins may be one of the molecular cues that restrict axonal regeneration after SCI. Rats received a contusive SCI at T10 and in situ hybridization studies 7 days posttrauma demonstrated: (i) a marked up-regulation of Eph B3 mRNA in cells located in the white matter at the lesion epicenter, but not rostral or caudal to the injury site, and (ii) an increase in Eph B3 mRNA in neurons in the ventral horn and intermediate zone of the gray matter, rostral and caudal to the lesion. Immunohistochemical analyses localizing Eph B3 protein were consistent with the mRNA results. Colocalization studies performed in injured animals demonstrated increased Eph B3 expression in white matter astrocytes and motor neurons of the gray matter. These results suggest that Eph B3 may contribute to the unfavorable environment for axonal regeneration after SCI.

ETS sites in the promoters of the matrix metalloproteinases collagenase (MMP-1) and stromelysin (MMP-3) are auxiliary elements that regulate basal and phorbol-induced transcription

The matrix metalloproteinases collagenase (MMP-1) and stromelysin (MMP-3) are often coordinately expressed, and their promoters contain similar regulatory elements, including an AP-1 site at about -70. There are, however, additional sequences including an adjacent ETS site at about -90 in both promoters, and a NIP (nuclear inhibitory protein) binding site in the stromelysin promoter. In this paper, we have investigated the role of these elements in transcriptional activation by phorbol myristate acetate (PMA). Using mobility shift assays, we demonstrate that in the collagenase promoter, PMA induction requires the binding of nuclear proteins to the ETS site as well as to the adjacent AP-1 element. In the stromelysin promoter, we used mutational analysis and DNA/protein interactions to illustrate a role for a single ETS site and for the NIP element in phorbol induction. These data suggest that ETS elements interact with other cis-acting sequences in these promoters to elicit transcriptional activation, and that the placement of the ETS sites in these promoters may influence transcriptional activity.

Induced PAI-1 mRNA expression and targeted protein accumulation are early G1 events in serum-stimulated rat kidney cells

Expression of plasminogen activator inhibitor type-1 (PAI-1), a member of the SERPIN gene family that functions to regulate the plasmin-based pericellular proteolytic cascade, is growth state-regulated in normal rat kidney (NRK) cells (Ryan and Higgins, 1990, J. Cell. Physiol., 155:376-384; Ryan et al., 1996, Biochem. J., 314:1041-1046). Comparative analysis of arrest states induced in NRK cells upon exposure to serum-deficient (0.5% FBS) or serum-free culture conditions served to define the kinetics of PAI-1 gene expression and fate of de novo-synthesized PAI-1 protein. While cells rendered quiescent in serum-free or serum-deficient media were equivalent with regard to the time course of PAI-1 mRNA induction, the level of expressed transcripts (27-fold vs. 12-fold) and accumulated saponin fraction PAI-1 protein (12-fold vs. 6-fold) were consistently greater in cells recruited into exponential growth phase from a serum-free as compared to a serum-deficient arrest condition. Relative PAI-1 mRNA abundance increased within 1-2 hr post-serum addition, was maximal at 4 hr, and declined rapidly thereafter; this time course of expression coupled with placement of entry into DNA synthetic phase at approximately 12 hr after stimulation indicates that PAI-1 induction is an early-to-mid G1 phase event. Induced PAI-1 protein was evident immunocytochemically within 2 hr of serum stimulation as a peripheral "rim" of accumulated protein restricted to the cellular ventral surface at the plane of the substrate. No PAI-1 was detected between individual cells suggesting that this protein may be targeted directly to the undersurface region. By 6 hr post-stimulation, the rim of PAI-1 deposition increased in intensity and broadened to occupy approximately 30 to 50% of the total undersurface area. Double-label immunocytochemistry indicated that accumulated PAI-1 was deposited in close proximity to, but not actually within, vinculin-containing focal contact structures. Potential functionality of induced PAI-1 expression to either the initiation or maintenance of the serum-stimulated phenotype was assessed using antibodies to PAI-1. The IgG fractions of two different antisera which neutralize the ability of PAI-1 to complex with and thereby inhibit the catalytic activity of urokinase plasminogen activator significantly reduced (by 25-35%) the incidence of cells displaying the serum-stimulated phenotype; antibodies that bind PAI-1 but do not block PAI-1 inhibitory activity were without effect. In view of the vagaries of antibody accessibility and in situ neutralizing activity (particularly in a region as structurally complex as the focal contact), these data may actually underestimate the importance of PAI-1 in maintaining the activated phenotype.

Transcriptional regulation of neurofilament expression by protein kinase A

RN46A cells, a conditionally immortalized neuronal cell line derived from E12 rat medullary raphe nucleus, upregulate low M(r) (68 kDa, neurofilament [NF]-L) and medium M(r) (160 kDa, NF-M) neurofilament protein expression upon activation of protein kinase A (PKA). To examine possible transcriptional regulation of neurofilament protein expression by PKA, two cell lines were used; RN46A cells and C alpha EV6 cells, a cell line derived from RN46A cells that stably expresses the catalytic subunit of PKA under the control of the metallothionein promoter. Treatment of RN46A cells with dbcAMP resulted in an increase in the steady-state levels of both NF-L and NF-M, but not high M(r) (200 kDa, NF-H) neurofilament mRNA. These increases were both time and dose dependent and were sensitive to treatment with the protein synthesis inhibitor cycloheximide. In C alpha EV6 cells, activation of PKA by 80 microM ZnSO4 upregulated the expression of C alpha mRNA with maximal levels reached 8 hr post-treatment and maintained at 24 hr. Reporter gene assays in C alpha EV6 cells following transfection with increasing lengths of the NF-L promoter demonstrated that both a putative Sp1-like and a cAMP response (CRE), but not a NGFI-A, element were likely involved in PKA-dependent activation of the NF-L promoter. Electrophoretic mobility shift assays confirmed these results but showed that the nuclear proteins induced by PKA which bound to the NF-L promoter Sp1-like sequence were not Sp1. Collectively, these data suggest that constitutively expressed Sp1 may be involved in basal NF-L promoter activity, and newly synthesized, PKA-dependent nuclear proteins may synergistically activate the rat NF-L promoter.

Induced PAI-1 mRNA expression and targeted protein accumulation are early G1 events in serum-stimulated rat kidney cells

Expression of plasminogen activator inhibitor type-1 (PAI-1), a member of the SERPIN gene family that functions to regulate the plasmin-based pericellular proteolytic cascade, is growth state-regulated in normal rat kidney (NRK) cells (Ryan and Higgins, 1990, J. Cell. Physiol., 155:376-384; Ryan et al., 1996, Biochem. J., 314:1041-1046). Comparative analysis of arrest states induced in NRK cells upon exposure to serum-deficient (0.5% FBS) or serum-free culture conditions served to define the kinetics of PAI-1 gene expression and fate of de novo-synthesized PAI-1 protein. While cells rendered quiescent in serum-free or serum-deficient media were equivalent with regard to the time course of PAI-1 mRNA induction, the level of expressed transcripts (27-fold vs. 12-fold) and accumulated saponin fraction PAI-1 protein (12-fold vs. 6-fold) were consistently greater in cells recruited into exponential growth phase from a serum-free as compared to a serum-deficient arrest condition. Relative PAI-1 mRNA abundance increased within 1-2 hr post-serum addition, was maximal at 4 hr, and declined rapidly thereafter; this time course of expression coupled with placement of entry into DNA synthetic phase at approximately 12 hr after stimulation indicates that PAI-1 induction is an early-to-mid G1 phase event. Induced PAI-1 protein was evident immunocytochemically within 2 hr of serum stimulation as a peripheral "rim" of accumulated protein restricted to the cellular ventral surface at the plane of the substrate. No PAI-1 was detected between individual cells suggesting that this protein may be targeted directly to the undersurface region. By 6 hr post-stimulation, the rim of PAI-1 deposition increased in intensity and broadened to occupy approximately 30 to 50% of the total undersurface area. Double-label immunocytochemistry indicated that accumulated PAI-1 was deposited in close proximity to, but not actually within, vinculin-containing focal contact structures. Potential functionality of induced PAI-1 expression to either the initiation or maintenance of the serum-stimulated phenotype was assessed using antibodies to PAI-1. The IgG fractions of two different antisera which neutralize the ability of PAI-1 to complex with and thereby inhibit the catalytic activity of urokinase plasminogen activator significantly reduced (by 25-35%) the incidence of cells displaying the serum-stimulated phenotype; antibodies that bind PAI-1 but do not block PAI-1 inhibitory activity were without effect. In view of the vagaries of antibody accessibility and in situ neutralizing activity (particularly in a region as structurally complex as the focal contact), these data may actually underestimate the importance of PAI-1 in maintaining the activated phenotype.

src-related tyrosine kinases regulate transcriptional activation of the interstitial collagenase gene, MMP-1, in interleukin-1-stimulated synovial fibroblasts

OBJECTIVE

To characterize tyrosine kinases that contribute to the transcription of interstitial collagenase.

METHODS

Four thousand six hundred fourteen basepairs of the rabbit collagenase promoter region were cloned and sequenced. Plasmids containing collagenase promoter fragments linked to the luciferase reporter gene were transiently transfected into primary rabbit synovial fibroblasts. Regulation of gene activation by inflammatory mediators and tyrosine kinase inhibitors was assessed. To identify specific tyrosine kinases that contribute to collagenase gene expression, v-src was transiently expressed in rabbit synovial fibroblasts along with collagenase promoter constructs, and basal and interleukin-(IL-l)-induced collagenase transcription was assayed.

RESULT

An inhibitor of src-related tyrosine kinases, herbimycin A, inhibited increases of collagenase messenger RNA in IL-1- and phorbol myristate acetate-treated fibroblasts. Transcriptional activation of collagenase by IL-1 was also inhibited by herbimycin A. Expression of v-src in synovial fibroblasts enhanced basal and IL-1-inducible transcription.

CONCLUSION

Activation of collagenase transcription by inflammatory mediators involves activation of an src-related tyrosine kinase.

Adequately Treated Remote Syphilis<br />Does Not Augment<br />CNS HIV-1 Expression

OBJECTIVE

The co-occurence of human immunodeficiency virus (HIV) infection and syphilis may accelerate the course of both infections. We investigated whether remote syphilis infection augmented the activation of central nervous system (CNS) HIV infection and increased the frequency of cerebrospinal fluid (CSF) abnormalities.

METHODS

The subjects consist of HIV seropositive men who had CSF as part of prospective neurological studies performed at the Johns Hopkins University. Prior syphilis infection was determined by measuring serum FTA-ABS. All subjects had received adequate treatment for syphilis with negative RPR's or RPR's &le; 1:8 and completed a full neurological examination and underwent lumbar punctures for analysis of cerebrospinal fluid. A range of CSF tests were performed including HIV culture, p24 antigen, &beta;₂ microglobulin (&beta;2M) and CSF/albumin ratios.

RESULTS

The FTA positive group was significantly older (p = .005), more advanced in HIV clinical staging (p = .04), had more minor neurological symptoms (p = .03), and was more likely to be on antiretroviral therapy (p = .03). No differences between FTA positive and FTA negative groups were observed either in the frequency of CFS anbormalities or the mean CSF values.

CONCLUSIONS

Based on these findings, it appears that adequately treated remote syphilis does not augment HIV-1 expression within the CNS.

Regulating expression of the gene for matrix metalloproteinase-1 (collagenase): mechanisms that control enzyme activity, transcription, and mRNA stability

Matrix metalloproteinase-1 (MMP-1) is one of three collagenases that can degrade the interstitial collagens, types I, II, and III at neutral pH. As these collagens are the most abundant proteins in the body, collagenase plays a critical role in modeling and remodeling the extracellular matrix. Therefore, it is not surprising that MMP-1 gene expression can be regulated at multiple points. Procollagenase can be activated by mechanisms that generate an active enzyme with differing specific activities, and the active enzyme can be inhibited by complexing with either the tissue inhibitor of metalloproteinases (TIMPs) or alpha 2 macroglobulin. The activator protein-1 (AP-1) site in the collagenase promoter plays a prominent role in the transcriptional control of the collagenase gene. It is essential for basal transcription, and contributes to induction by phorbol esters, although other sites in the proximal promoter are essential. In contrast, transactivation by cytokines such as Interleukin-1 depends on sequences in more distal regions of the promoter. Posttranscriptional mechanisms also regulate gene expression, and several cytokines and growth factors increase the stability of the collagenase transcript. Finally, glucocorticoid hormones repress transcription of the collagenase gene by the interaction of glucocorticoid receptors with the AP-1 proteins, Fos and Jun. Retinoids also suppress transcription by mechanisms that involve down-regulation of fos and jun mRNA, sequestration of Fos and Jun proteins, and the formation of complexes of retinoic acid receptors (RAR/RXR heterodimers) and AP-1 proteins on the DNA. These multiple points of regulation assure precise control of collagenolytic activity in a variety of physiologic and pathologic conditions.

Two activator protein-1 elements in the matrix metalloproteinase-1 promoter have different effects on transcription and bind Jun D, c-Fos, and Fra-2

Collagenase (matrix metalloproteinase-1, MMP-1) plays a central role in connective tissue metabolism as the only enzyme capable of degrading interstitial collagens at neutral pH. We used fragments of the rabbit collagenase promoter ranging from 1800 to 182 bp to measure transcriptional activity of the activator protein-1 (AP-1) site at -77. Mutation at -77 in this sequence greatly reduced basal transcription in all constructs. However, mutant constructs with at least 321 bp of promoter responded to phorbol myristate acetate, similar to their native counterparts, implicating upstream regions in mediating this response. Through mutagenesis and analysis of DNA-protein interactions, we also identified and characterized a novel AP-1 site at -186. Mutation at -186 in 321 bp of promoter modestly lowered basal activity but, in contrast to mutation at -77, reduced phorbol responsiveness by 50%. Mobility shift assays demonstrated specific inducible binding at both sites. DNA/protein complexes at both AP-1 sites contain c-Fos and Jun D proteins, while Fra-2 is present only at the -77 site. These studies (1) demonstrate cooperativity between these two AP-1 sites, (2) implicate the -186 site in phorbol inducibility and (3) identify specific members of the Fos and Jun families binding to these sites.

Do HMOs care for the chronically ill?

This DataWatch refutes the notion that chronic illness is more prevalent among persons covered by indemnity insurance than by health maintenance organizations (HMOs). This is true even when health status and sociodemographic factors are accounted for in the analysis. The study analyzes the prevalence of chronic illness among privately insured nonelderly persons in HMOs and indemnity plans, using data from the 1992 National Health Interview Survey. More data are needed to examine this issue for Medicare and Medicaid populations.

Distinct regulatory pathways control neurofilament expression and neurotransmitter synthesis in immortalized serotonergic neurons

Following infection of dissociated embryonic day 13 rat medullary raphe cells with a retrovirus encoding the temperature-sensitive mutant of SV40 large T-antigen (T-ag), a neuronal cell line, RN46A, was cloned by serial dilution. At 33 degrees C, RN46A cells express nuclear T-ag immunoreactivity and divide with a doubling time of 9 hr. Undifferentiated RN46A cells express low levels of neuron-specific enolase (NSE) and low (NF-L)-and medium (NF-M)- but not high (NF-H)-molecular-weight neurofilament proteins. Under differentiation conditions, RN46A cells cease dividing, take on a neuronal morphology, and express enhanced levels of NSE and all three NF proteins. Elevation of intracellular cAMP levels increases neurofilament protein expression, whereas activators of various other intracellular second messenger systems have no effect. Differentiated RN46A cells express low-affinity nerve growth factor (NGF) receptor (p75NGFR) and are immunoreactive using an antibody that recognizes the carboxy-terminal 13 amino acids of all three trk proteins (pan-trk). Both immunoreactivities could be potentiated by treatment with brain-derived neurotrophic factor (BDNF), NGF, and adrenocorticotropic hormone, fragment 4-10 (ACTH4-10). Differentiated RN46A cells express low levels of tryptophan hydroxylase (TPH) immunoreactivity, which could be enhanced by treatment with ACTH4-10, BDNF, or NGF. Low levels of serotonin immunoreactivity are detected in differentiated RN46A cells, and this was potentiated by differentiating RN46A cells with BDNF for 8 d and 40 mM KCl for days 4-8. HPLC analysis confirmed these immunohistochemical data. RN46A cells should prove useful to elucidate intracellular mechanisms that control neurofilament assembly and 5-HT expression in differentiating raphe neurons.

Differentiation of an immortalized CNS neuronal cell line decreases their susceptibility to cytotoxic T cell lysis in vitro

RN33B cells are a temperature-sensitive neuronal cell line derived from rat E12 medullary raphe nucleus (Whittemore and White (1993) Brain Research 615, 27-40). Undifferentiated RN33B cells express class I but not class II antigens of the major histocompatibility complex (MHC), and intercellular adhesion molecule-1 (ICAM-1), a ligand for lymphocyte function associated antigen-1 (LFA-1), expressed on cytotoxic T lymphocytes (CTLs). Treatment of undifferentiated RN33B cells with interferon-gamma (IFN-gamma) upregulated both class I MHC and ICAM-1. After neuronal differentiation, expression of class I MHC antigens or ICAM-1 was undetected, even after IFN-gamma treatment. The neuronally differentiated RN33B cells were also markedly less susceptible to lysis by alloantigen-specific CTLs. These data suggest that intrinsic to the differentiation of CNS neurons is a mechanism to escape CTL-mediated cell lysis.

Induction of collagenase and stromelysin gene expression by mechanical injury in a vascular smooth muscle-derived cell line

We describe a novel system for studying the production of matrix metalloproteinases types I and III (collagenase and stromelysin) by a vascular smooth muscle cell line (Rb-1 cells) in response to mechanical injury. Highly confluent Rb-1 cells are disrupted by passing a plastic comb around the plate to clear a series of circumferential paths, which are bordered by two ridges of displaced cells. Over the next 24 hours, cells migrate into the cleared areas. Northern blot analysis demonstrates the accumulation of mRNAs for collagenase and stromelysin during this process, although they are undetectable prior to injury. Cotreatment with all-trans-retinoic acid (10(-6) M) markedly decreases the level of mRNAs induced by injury, whereas dexamethasone (10(-7) M) causes only a slight reduction. In situ hybridization studies for stromelysin mRNA and immunohistochemical staining for collagenase protein on plates of injured cells showed the highest levels of stromelysin mRNA in cells in the ridges left by the injury; lower levels were observed in some cells migrating into the clear region. The same pattern of expression was observed when cells were stained with antiserum to collagenase protein. Nuclear run-on assays demonstrated increases in transcription of stromelysin and collagenase genes following injury. Transient transfection of cells with a vector containing the luciferase gene driven by a wild-type promoter comprising 1.8 kb of the 5'-flanking region of the rabbit collagenase gene showed increased activity associated with injury. We conclude that: (1) mechanical injury is associated with induction of mRNAs for the metalloproteinases collagenase and stromelysin, (2) retinoic acid effectively antagonizes this responses, and (3) the increase in steady-state mRNA levels is, at least in part, transcriptionally mediated. Thus our data suggest a role for mechanical forces in initiating the changes in gene expression in vascular smooth muscle cells following arterial injury in vivo.

Target regulation of neuronal differentiation in a temperature-sensitive cell line derived from medullary raphe

Following infection of dissociated embryonic day 13 rat medullary raphe cells with a retrovirus encoding the temperature-sensitive mutant of SV40 large T antigen, a clonal cell line, RN33B, was isolated by serial dilution. At 33 degrees C, RN33B cells divide with a doubling time of 48 h and show T antigen, vimentin, nestin, diffuse neuron-specific enolase, and low and medium molecular weight neurofilament immunoreactivities. RN33B cells are immortal, but not transformed, as they will not grow in soft agar. At non-permissive temperature (38.5 degrees C), T antigen expression is markedly decreased and RN33B cells cease mitotic activity and differentiate with phase bright cell bodies and 'neuritic-like' processes. Differentiated RN33B cells express enhanced neuronal-specific protein expression but do not synthesize astrocytic or oligodendrocytic-specific proteins. Moreover, differentiated RN33B cells returned to 33 degrees C re-express T antigen, but do not de-differentiate or begin dividing. Co-culture with embryonic hippocampus and cerebral cortex, but not medullary raphe or spinal cord, resulted in significantly greater survival, more complex neuronal morphology, and enhanced expression of neuronal-specific antigens. Immunohistochemical and Northern blot analysis revealed high levels of low affinity NGF receptor protein and mRNA in differentiated RN33B cells. PCR analysis demonstrated the presence of trkB, but not trkA or trkC, mRNA in both undifferentiated and differentiated RN33B cells. These data suggest that the observed target regulation of RN33B cell neuronal differentiation in co-culture may be mediated by neurotrophin(s).

Gastro-intestinal bleeding in acquired von Willebrand's disease: efficacy of high-dose immuno-globulin where substitution treatments failed

We report a case of acquired von Willebrand's disease with severe and persistent gastro-intestinal bleeding from multiple bleeding points. He received maximum substitution treatment including factor VIII concentrates, cryoprecipitate and platelets. He also received DDAVP. There was no change in the rate of blood loss. He was then treated with high-dose intravenous gamma-globulin and the blood loss stopped abruptly. He remained well for several months when bleeding recommenced and he again responded promptly to gamma-globulin. This is a useful maintenance treatment for patients with acquired von Willebrand's disease.

In vitro labeling strategies for identifying primary neural tissue and a neuronal cell line after transplantation in the CNS

Potential labels for identifying embryonic raphe neurons and a clonal, neuronally differentiating, raphe-derived cell line, RN33B, in CNS transplantation studies were tested by first characterizing the labels in vitro. The labels that were tested included 4',6-diamidino-2-phenylindole hydrochloride, 1,1'-dioctadecyl-3,3,3'-tetramethylindocarbocyanine perchlorate, the Escherichia coli lacZ gene, Fast Blue, Fluoro-Gold, fluorescein-conjugated latex microspheres, fluorescein isothiocyanate-conjugated or nonconjugated Phaseolus vulgaris leucoagglutinin, methyl o-(6-amino-3'-imino-3H-xanthen-9-yl) benzoate monohydrochloride, or tetanus toxin C fragment. Subsequently, the optimal in vitro labels for embryonic raphe neurons and for RN33B cells were characterized in vivo after CNS transplantation. In vitro, 1,1'-dioctadecyl-3,3,3'-tetramethylindocarbocyanine perchlorate (DiI) optimally labeled embryonic neurons. The Escherichia coli lacZ gene optimally labeled RN33B cells. Most labels were rapidly diluted in cultures of embryonic astrocytes and proliferating RN33B cells. Some labels were toxic and were often retained in cellular debris. In vivo, DiI was visualized in transplanted, DiI-labeled raphe neurons, but not in astrocytes up to 1 mo posttransplant. DiI-labeled host cells were seen after transplantation of lysed, DiI-labeled cells. beta-Galactosidase was visualized in transplanted, Escherichia coli lacZ gene-labeled RN33B cells after 15 days in vivo. No beta-galactosidase was seen in host cells after transplantation of lysed, lacZ-labeled RN33B cells. The results demonstrate that labels for use in CNS transplantation studies should be optimized for the specific population of donor cells under study, with the initial step being characterization in vitro followed by in vivo analysis. Appropriate controls for false-positive labeling of host cells should always be assessed.

Treatment of Haemophilus aphrophilus endocarditis with ciprofloxacin

A patient with Haemophilus aphrophilus endocarditis was successfully treated with ciprofloxacin. The response to treatment with cefotaxime and netilmicin for 12 days was poor but was satisfactory to a 6 weeks' course of ciprofloxacin.

Effects of deuterium oxide and temperature on heart rate in Drosophila melanogaster

A non-intrusive optical technique has been developed to monitor heartbeat in late third-instar Drosophila larvae. Heartbeat in this insect is an oscillation that is not temperature compensated. Deuterium oxide lengthens the period of a number of high and low frequency oscillators and clocks in a variety of organisms. To determine whether deuterium affects heart rate, flies were raised on proteated and deuterated media and their heartbeat was monitored at four temperatures ranging from 18 to 33 degrees C. The rate of heartbeat increased linearly with increasing temperature, and decreased with increasing concentrations of deuterium. There was a significant interaction between temperature and deuterium: the higher the concentration of deuterium oxide the less temperature-sensitive was the heart rate. Raising temperatures also increased the amount of "noise" in the rhythm: signal-to-noise ratio, which characterizes the amount of power in a rhythmic signal, decreased with increasing temperatures. Deuterium oxide had no effect on signal-to-noise ratio.

The evolution of back school

This article outlines the evolution of formalized education programs for back pain sufferers. The development of back school and stabilization training is described, and the need for further patient education is emphasized.

Differential effects of acidic and basic fibroblast growth factors on spinal cord cholinergic, GABAergic, and glutamatergic neurons

When spinal cord cultures from embryonic day 12 rats were cultured at low density, both acidic and basic fibroblast growth factors significantly increased neuronal survival and neurite outgrowth in a dose-dependent manner. The effects of acidic fibroblast growth factor were independent of heparin, in contrast to its mitogenic effects on both NIH3T3 cells and cerebral cortical astrocytes. In high-density cultures, acidic fibroblast growth factor increased choline acetyltransferase activity by 57%, glutamic acid decarboxylase activity by 58%, and aspartate aminotransferase activity by 65%. Basic fibroblast growth factor increased choline acetyltransferase activity by 73% and glutamic acid decarboxylase activity by 200% but decreased aspartate aminotransferase activity by 40%. Growing these cultures in the presence of a mitotic inhibitor did not significantly alter the effect of acidic or basic fibroblast growth factor on these enzyme activities. These results demonstrate that acidic and basic fibroblast growth factors differentially affect neurotransmitter enzyme levels of multiple classes of neurons, rather than having effects on a single neuronal population.

Quality assurance. A staff development concern

To ensure high standards of nursing care, staff development educators need to develop a quality assurance (QA) plan specifically designed to monitor the outcome of educational activities. This article focuses on the design of a QA plan and its use in assessing nursing education programs for their quality, appropriateness, and clinical application.

Acidic and basic fibroblast growth factor levels in spinal cord cultures are not regulated by alterations in heparan sulfate proteoglycan expression

The present study was undertaken to assess both the levels of acidic and basic fibroblast growth factors in spinal cord cultures and to determine how they were presented to responsive cells. Western blots detected a single acidic fibroblast growth factor-like protein (17 kDa) and two (18 kDa, 24 kDa) basic fibroblast growth factor-immunoreactive proteins, the levels of which varied with the antibody used. Levels of all three proteins were unaltered in cultures grown in the presence of a mitotic inhibitor, which greatly reduced the number of astrocytes. Cell blots showed increased survival of spinal cord neurons at Mr that corresponded with the three proteins detected immunologically. Solubilized cultures separated on a P100 column showed mitogenic activity for NIH3T3 cells from 17-18 and 24 kDa fractions. Treatment of the cultures with heparitinase did not decrease the levels of acidic and basic fibroblast growth factors detected by Western blots, suggesting that these proteins were not associated with extracellular membrane heparan sulfate proteoglycans. The major fraction of both proteins appeared to be intracellular with a minor amount complexed with extracellular matrix proteins. An inhibitor of xylose-linked proteoglycan synthesis significantly altered heparan sulfate proteoglycan deposition into extracellular matrix, but did not alter the levels of acidic or basic fibroblast growth factors detected by Western blots, or the levels of choline acetyltransferase, glutamic acid decarboxylase, or aspartate aminotransferase activities. These results indicate that both acidic and basic fibroblast growth factors are stored predominantly intracellularly, with only a minor fraction complexed with extracellular proteins. We suggest that these intracellular proteins may be released following injury in the CNS and mediate a cascade of neuroprotective events.

Inactivation and stability of viral diagnostic reagents treated by gamma radiation

The objective of this study was to apply the pertinent findings from gamma inactivation of virus infectivity to the production of high quality diagnostic reagents. A Gammacell 220 (Atomic Energy of Canada, Ltd., Ottawa, Canada) was used to subject 38 viruses grown in either susceptible tissue cultures or embryonated chicken eggs to various doses of gamma radiation from a cobalt-60 source. The radiation required to reduce viral infectivity was 0.42 to 3.7 megarads (Mrad). The effect of gamma treatment on the antigenic reactivity of reagents for the complement fixation (CF), hemagglutination (HA) and neuraminadase assays was determined. Influenza antigens inactivated with 1.7 Mrad displayed comparable potency, sensitivity, specificity and stability to those inactivated by standard procedures with beta-propiolactone (BPL). Significant inactivation of influenza N1 and B neuraminidase occurred with greater than 2.4 Mrad radiation at temperatures above 4 degrees C. All 38 viruses were inactivated, and CF or HA antigens were prepared successfully. Antigenic potency remained stable with all antigens for 3 years and with 83% after 5 years storage. Influenza HA antigens evaluated after 9 years of storage demonstrated 86% stability. Gamma radiation is safer than chemical inactivation procedures and is reliable and effective replacement for BPL in preparing diagnostic reagents.

Humor: a teaching strategy to promote learning

Staff development educators strive to identify methods to facilitate learners' receptivity to information presented, willingness to explore new ideas, and ability to analyze relationships among concepts. This article focuses on the value of humor as a teaching strategy and suggests methods for its incorporation into educational offerings. A "Humor Profile" is provided to give nurse educators an indication of the degree to which they need to improve their use of humor as a teaching strategy.