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Peripherally-induced regulatory T cells (pTregs) expressing the retinoic acid receptor-related orphan-receptor gamma t (RORγt) are indispensable for intestinal immune homeostasis. Nuclear factor kappa family members regulate the differentiation of thymic Tregs and promote their survival in the periphery. However, the Treg intrinsic molecular mechanisms controlling the size of the pTregs in the intestine and associated lymphoid organs remain unclear. Here, we provide direct evidence that B-cell lymphoma 3 (Bcl3) limits the development of pTregs in a T cell-intrinsic manner. Moreover, the absence of Bcl3 allowed for the formation of an unusual intestinal Treg population co-expressing the transcription factors Helios and RORγt. The expanded RORγt + Treg populations in the absence of Bcl3 displayed an activated phenotype and secreted high levels of the anti-inflammatory cytokines interleukin (IL)-10 and transforming growth factor beta. They were fully capable of suppressing effector T cells in a transfer colitis model despite an intrinsic bias to trans-differentiate toward T helper 17-like cells. Finally, we provide a Bcl3-dependent gene signature in pTregs including altered responsiveness to the cytokines IL-2, IL-6, and tumor necrosis factor alpha. Our results demonstrate that Bcl3 acts as a molecular switch to limit the expansion of different intestinal Treg subsets and may thus serve as a novel therapeutic target for inflammatory bowel disease by restoring intestinal immune tolerance., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Desmosomes are dynamic complex protein structures involved in cellular adhesion. Disruption of these structures by loss-of-function variants in desmosomal genes leads to a variety of skin- and heart-related phenotypes. In this study, we report TUFT1 as a desmosome-associated protein, implicated in epidermal integrity. In two siblings with mild skin fragility, woolly hair, and mild palmoplantar keratoderma but without a cardiac phenotype, we identified a homozygous splice-site variant in the TUFT1 gene, leading to aberrant mRNA splicing and loss of TUFT1 protein. Patients' skin and keratinocytes showed acantholysis, perinuclear retraction of intermediate filaments, and reduced mechanical stress resistance. Immunolabeling and transfection studies showed that TUFT1 is positioned within the desmosome and that its location is dependent on the presence of the desmoplakin carboxy-terminal tail. A Tuft1-knockout mouse model mimicked the patients' phenotypes. Altogether, this study reveals TUFT1 as a desmosome-associated protein, whose absence causes skin fragility, woolly hair, and palmoplantar keratoderma., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The COVID-19 pandemic has caused the death of millions and many more have been infected worldwide. The causative virus, SARS-CoV-2, affects the lung where it elicits an aggressive inflammatory response leading to respiratory failure in severe cases. This infection has been linked to pulmonary fibrosis, a process characterized by fibroproliferation and the exaggerated deposition of collagen and other extracellular matrices. These events damage the lung architecture, especially its gas-exchanging units, leading to hypoxemic respiratory failure. The mechanisms by which the virus affects the lung remain incompletely understood, but it is postulated that after entering the airways, the virus binds to Angiotensin Converting Enzyme (ACE) receptors on the surface of epithelial cells, not only stimulating oxidative stress and inflammation, but also promoting the expression of soluble pro-fibrotic factors responsible for the accumulation of fibroblasts, their activation into myofibroblasts, and their unregulated expression of extracellular matrices. These events may trigger the rapid progression or exacerbation of underlying interstitial lung disorders or promote fibrosis in a previously healthy lung. Although the natural progression of such conditions cannot always be predicted, fibrosis may progress even after the virus has been eliminated or, in cases where it does not progress, may become irreversible, leading to long-standing symptoms like shortness of breath and exercise intolerance resulting from loss of lung function. Although COVID-19 related pulmonary fibrosis is not common, preventive measures like vaccination are encouraged, as they are expected to reduce infection or its severity, thereby decreasing the possibility of life-changing respiratory conditions such as pulmonary fibrosis., Competing Interests: Declaration of Competing Interest The authors do not have conflicts of interest related to the topic of COVID and pulmonary fibrosis. J.R. is an investigator on clinical trials sponsored by industry including Boehringer Ingelheim, Genentec, F. Hoffmann-LaRoach, Horizon Therapeutics, Galapagos, and Syneos Health., (Copyright © 2023. Published by Elsevier Inc.)

Background: Advanced therapies in neurosurgery, such as deep brain stimulation (DBS), would benefit from improved patient education materials. Three-dimensional (3D) printed anatomical models represent a recent development for improving patient education for neurosurgical procedures., Methods: In this study, 40 patients undergoing DBS surgery consultation were randomly assigned to 1 of 2 groups: an experimental group, which received a demonstration of DBS therapeutic neuroanatomical targets in a 3D printed brain model plus standard patient education (PE), or a control group, which received standard PE alone., Results: Patients in the DBS model plus PE group showed a significant increase in patient confidence and understanding of the brain structures targeted during a DBS procedure compared with patients in the PE-only group (P < 0.01). There was no difference in perceived risk, comfort, or anxiety related to the procedure., Conclusions: In the first randomized controlled study to our knowledge of 3D printed models for DBS consultation, our results demonstrate that patients had improved understanding of their therapy with the models. However, the models alone did not affect risk evaluation or comfort with surgery. A 3D printed brain model may help improve patient understanding of DBS surgery., (Published by Elsevier Inc.)

Transcription factors of the NF-κB family play a crucial role for immune responses by activating the expression of chemokines, cytokines, and antimicrobial peptides involved in pathogen clearance. IκBζ, an atypical nuclear IκB protein and selective coactivator of particular NF-κB target genes, has recently been identified as an essential regulator for skin immunity. This study discovered that IκBζ is strongly induced in keratinocytes that sense the fungal glucan zymosan A. Additionally, IκBζ is essential for the optimal expression of proinflammatory genes, such as IL6, CXCL5, IL1B, or S100A9. Moreover, this study found that IκBζ was not solely regulated on the transcriptional level but also by phosphorylation events. This study identified several IκBζ phosphorylation sites, including a conserved cluster of threonine residues located in the N-terminus of the protein, which can be phosphorylated by MAPKs. Surprisingly, IκBζ phosphorylation at this threonine cluster promoted the recruitment of histone deacetylase 1 to specific target gene promoters and, thus, negatively controlled transcription. Taken together, this study proposes a model of how an antifungal response translates to the expression of proinflammatory cytokines and highlights an additional layer of complexity in the regulation of the NF-κB responses in keratinocytes., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Diffuse large B-cell lymphoma (DLBCL) represents the most common adult lymphoma and can be divided into 2 major molecular subtypes: the germinal center B-cell-like and the aggressive activated B-cell-like (ABC) DLBCL. Previous studies suggested that chronic B-cell receptor signaling and increased NF-κB activation contribute to ABC DLBCL survival. Here we show that the activity of the transcription factor NFAT is chronically elevated in both DLBCL subtypes. Surprisingly, NFAT activation is independent of B-cell receptor signaling, but mediated by an increased calcium flux and calcineurin-mediated dephosphorylation of NFAT. Intriguingly, although NFAT is activated in both DLBCL subtypes, long-term calcineurin inhibition with cyclosporin A or FK506, both clinically approved drugs, triggers potent cytotoxicity specifically in ABC DLBCL cells. The antitumor effects of calcineurin inhibitors are associated with the reduced expression of c-Jun, interleukin-6, and interleukin-10, which were identified as NFAT target genes that are particularly important for the survival of ABC DLBCL. Furthermore, calcineurin blockade synergized with BCL-2 and MCL-1 inhibitors in killing ABC DLBCL cells. Collectively, these findings identify constitutive NFAT signaling as a crucial functional driver of ABC DLBCL and highlight calcineurin inhibition as a novel strategy for the treatment of this aggressive lymphoma subtype., (© 2020 by The American Society of Hematology.)

Context: Optimal advance care planning allows patients to articulate their values as a touchstone for medical decision making. Ideally, this occurs when patients are clinically stable, and with opportunities for iteration as the clinical situation unfolds., Objectives: Testing feasibility and acceptability in busy outpatient oncology clinics of a novel program of systematic, oncology nurse-led values discussions with all new cancer patients., Methods: Within an institutional initiative integrating primary and specialist palliative care from diagnosis for all cancer patients, oncology nurses were trained to use specific questions and an empathic communication framework to discuss health-related values during outpatient clinic visits. Nurses summarized discussions on a template for patient verification, oncologist review, and electronic medical record documentation. Summaries were reviewed with the patient at least quarterly. Feasibility and acceptability were evaluated in three clinics for patients with hematologic or gastrointestinal malignancies., Results: Oncology nurses conducted 177 total discussions with 67 newly diagnosed cancer patients (17 with hematologic and 50 with gastrointestinal malignancies) over two years. No patient declined participation. Discussions averaged eight minutes, and all patients verified values summaries. Clinic patient volume was maintained. Of 31 patients surveyed, 30 (97%) reported feeling comfortable with the process, considered it helpful, and would recommend it to others. Clinicians strongly endorsed the values discussion process., Conclusion: Nurse-led discussions of patient values soon after diagnosis are feasible and acceptable in busy oncology clinics. Further research will evaluate the impact of this novel approach on additional patient-oriented outcomes after broader dissemination of this initiative throughout our institution., (Copyright © 2019 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.)

Plants tolerate large variations in the intensity of the light environment by controlling the efficiency of solar to chemical energy conversion. To do this, plants have a mechanism to detect the intensity, duration, and change in light as they experience moving shadows, flickering light, and cloud cover. Sugars are the primary products of CO 2 fixation, a metabolic pathway that is rate limited by this solar energy conversion. We propose that sugar is a signal encoding information about the intensity, duration and change in the light environment. We previously showed that the Arabidopsis heterotrimeric G protein complex including its receptor-like Regulator of G signaling protein, AtRGS1, detects both the concentration and the exposure time of sugars (Fu et al., 2014. Cell 156: 1084-1095). This unique property, designated dose-duration reciprocity, is a behavior that emerges from the system architecture / system motif. Here, we show that another property of the signaling system is to detect large changes in light while at the same time, filtering types of fluctuation in light that do not affect photosynthesis efficiency. When AtRGS1 is genetically ablated, photosynthesis efficiency is reduced in a changing- but not a constant-light environment. Mathematical modeling revealed that information about changes in the light environment is encoded in the amount of free AtRGS1 that becomes compartmentalized following stimulation. We propose that this property determines when to adjust photosynthetic efficiency in an environment where light intensity changes abruptly caused by moving shadows on top of a background of light changing gradually from sun rise to sun set and fluctuating light such as that caused by fluttering leaves., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Neutralizing anti-drug antibodies (NAbs) against therapeutic interferon beta (IFNβ) in people with multiple sclerosis (MS) are measured with cell-based bioassays. The aim of this study was to redevelop and validate two luciferase reporter-gene bioassays, LUC and iLite, using a cut-point approach to identify NAb positive samples. Such an approach is favored by the pharmaceutical industry and governmental regulatory agencies as it has a clear statistical basis and overcomes the limitations of the current assays based on the Kawade principle. The work was conducted following the latest assay guidelines. The assays were re-developed and validated as part of the "Anti-Biopharmaceutical Immunization: Prediction and analysis of clinical relevance to minimize the risk" (ABIRISK) consortium and involved a joint collaboration between four academic laboratories and two pharmaceutical companies. The LUC assay was validated at Innsbruck Medical University (LUCIMU) and at Rigshospitalet (LUCRH) Copenhagen, and the iLite assay at Karolinska Institutet, Stockholm. For both assays, the optimal serum sample concentration in relation to sensitivity and recovery was 2.5% (v/v) in assay media. A Shapiro-Wilk test indicated a normal distribution for the majority of runs, allowing a parametric approach for cut-point calculation to be used, where NAb positive samples could be identified with 95% confidence. An analysis of means and variances indicated that a floating cut-point should be used for all assays. The assays demonstrated acceptable sensitivity for being cell-based assays, with a confirmed limit of detection in neat serum of 1519 ng/mL for LUCIMU, 814 ng/mL for LUCRH, and 320 ng/mL for iLite. Use of the validated cut-point assay, in comparison with the previously used Kawade method, identified 14% more NAb positive samples. In conclusion, implementation of the cut-point design resulted in increased sensitivity to detect NAbs. However, the clinical significance of these low positive titers needs to be further evaluated., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Large-scale electron microscopy ("nanotomy") allows straight forward ultrastructural examination of tissue, cells, organelles, and macromolecules in a single data set. Such data set equals thousands of conventional electron microscopy images and is freely accessible (www.nanotomy.org). The software allows zooming in and out of the image from total overview to nanometer scale resolution in a 'Google Earth' approach. We studied the life-threatening human autoimmune blistering disease pemphigus, using nanotomy. The pathomechanism of cell-cell separation (acantholysis) that underlies the blistering is poorly understood. Ultrastructural examination of pemphigus tissue revealed previously unreported findings: (i) the presence of double-membrane structures between cells in all pemphigus types; (ii) the absence of desmosomes around spontaneous blisters in pemphigus foliaceus (PF); (iii) lower level blistering in PF when force induced; and (iv) intercellular widening at non-acantholytic cell layers. Thus, nanotomy delivers open-source electron microscopic maps of patient tissue, which can be analyzed for additional anomalies from any computer by experts from different fields.

All protein drugs (biologicals) have an immunogenic potential and we are armed with multiple guidelines, regulatory documents and white papers to assist us in assessing the level of risk for unwanted immunogenicity of new biologicals. However, for certain biologicals, significant immunogenicity becomes only apparent after their use in patients. Causes of immunogenicity are multifactorial but not yet fully understood. Within the pharmaceutical industry there are only a few opportunities to openly discuss the causes and consequences of immunogenicity with regard to the development of new biologicals. The annual Open Scientific Symposium of the European Immunogenicity Platform (EIP) is one such meeting that brings together scientists and clinicians from academia and industry to build know-how and expertise in the field of immunogenicity. The critical topics discussed at the last EIP meeting (February 2014) will be reviewed here. The current opinion of this expert group is that the assessment of unwanted immunogenicity can be improved by using prediction tools, optimizing the performance of immunogenicity assays and learning from the clinical impact of other biologicals that have already been administered to patients. A multidisciplinary approach is warranted to better understand and minimize drug immunogenicity and its clinical consequences., (Copyright © 2015 Elsevier B.V. All rights reserved.)

There is much debate in the pharmaceutical industry on how to translate the current guidelines on immunogenicity testing for biotherapeutics into a testing strategy that suits the specific requirements of individual drug candidates. In this paper, member companies from the European immunogenicity platform (EIP) present a consensus view on the essential requirements for immunogenicity testing of a biotherapeutic throughout the various phases of drug development, to ensure patient safety and to enable successful market entry. Our aim is to open the debate and provoke discussion on this important topic which is unique to biotherapeutic drug development. The scope of this paper is limited to aspects relevant to biotherapeutic drug development and does not include fundamental academic studies of immunogenicity. Here, we propose two pre-defined testing strategies for the detection and characterization of anti-drug antibody (ADA) responses where the different strategies are based on the phase of development for a biotherapeutic, a. without (category 1) and b. with (category 2) the expected potential to elicit ADA mediated severe clinical consequences. The harm of a potential ADA response determines which of the two testing strategies is adopted. Rather than replacing the overall risk assessment which is known to be challenging and multi-factorial, the testing strategy selection is a starting point for immunogenicity testing which adapts throughout drug development as more information becomes available. The scientific rationale on which the "case-by-case" approach advocated in white papers and guidance documents may be translated for each individual drug development program is provided and, underpins the recommendations made here., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Acute cardiac calcification is a clinical entity that may develop over days to months and is usually localized to areas of healed myocardial infarction, cardiac surgery or trauma. We present an unusual case of rapidly developing non-ischemic cardiac calcification in the setting of sepsis and end stage renal disease resulting in acute diastolic dysfunction and cardiac collapse diagnosed by computed tomography (CT) and confirmed by autopsy. We propose that dedicated cardiac CT may provide the most accurate means to detect cardiac calcification., (Copyright © 2013 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Caliciviridae are RNA viruses with a single-stranded, positively oriented polyadenylated genome, responsible for a broad spectrum of diseases such as acute gastroenteritis in humans. Recently, analyses on the structures and functionalities of the RNA-dependent RNA polymerase (RdRp) from several Caliciviruses have been reported. The RdRp is predicted to play a key role in genome replication, as well as in synthesis and amplification of additional subgenomic RNA. Starting from the crystal structures of human Norovirus (hNV) RdRp, we performed an in silico docking search to identify synthetic compounds with predicted high affinity for the enzyme active site. The best-ranked candidates were tested in vitro on murine Norovirus (MNV) and hNV RdRps to assay their inhibition of RNA polymerization. The results of such combined computational and experimental screening approach led to the identification of two high-potency inhibitors: Suramin and NF023, both symmetric divalent molecules hosting two naphthalene-trisulfonic acid heads. We report here the crystal structure of MNV RdRp alone and in the presence of the two identified inhibitors. Both inhibitory molecules occupy the same RdRp site, between the fingers and thumb domains, with one inhibitor head close to residue 42 and to the protein active site. To further validate the structural results, we mutated Trp42 to Ala in MNV RdRp and the corresponding residue (i.e., Tyr41 to Ala) in hNV RdRp. Both NF023 and Suramin displayed reduced inhibitory potency versus the mutated hNV RdRp, thus hinting at a conserved inhibitor binding mode in the two polymerases., (Copyright © 2012. Published by Elsevier Ltd.)

The feasibility, value and risk of percutaneous renal biopsy (PRB) in liver transplant candidates with renal failure are unknown. PRB was performed on 44 liver transplant candidates with renal failure of undetermined etiology and glomerular filtration rate (GFR) <40 mL/min/1.73 m(2) (n = 37) or on renal replacement therapy (RRT) (n = 7). Patients with >or=30% interstitial fibrosis (IF), >or=40% global glomerulosclerosis (gGS) and/or diffuse glomerulonephritis were approved for simultaneous-liver-kidney (SLK) transplantation. Prebiopsy GFR, urinary sodium indices, dependency on RRT and kidney size were comparable between 27 liver-transplant-alone (LTA) and 17 SLK candidates and did not relate to the biopsy diagnosis. The interobserver agreement for the degree of IF or gGS was moderate-to-excellent. After a mean of 78 +/- 67 days, 16 and 8 patients received LTA and SLK transplants. All five LTA recipients on RRT recovered kidney function after transplantation and serum creatinine was comparable between LTA and SLK recipients at last follow-up. Biopsy complications developed in 13, of these, five required intervention. PRB is feasible in liver transplant candidates with renal failure and provides reproducible histological information that does not relate to the pretransplant clinical data. Randomized studies are needed to determine if PRB can direct kidney allocation in this challenging group of liver transplant candidates.

Copper is an essential trace element necessary for normal growth and development. During pregnancy, copper is transported from the maternal circulation to the fetus by mechanisms which have not been clearly elucidated. The copper uptake protein, hCTR1 is predicted to play a role in copper transport in human placental cells. This study has examined the expression and localisation of hCTR1 in human placental tissue and Jeg-3 cells. In term placental tissue the hCTR1 protein was detected as a 105 kDa protein, consistent with the size of a trimer which may represent the functional protein. A 95 kDa band, possibly representing the glycosylated protein, was also detected. hCTR1 was localised within the syncytiotrophoblast layer and the fetal vascular endothelial cells in the placental villi and interestingly was found to be localised toward the basal plasma membrane. It did not co-localise with either the Menkes or the Wilson copper transporting ATPases. Using the placental cell line Jeg-3, it was shown that the 35 kDa monomer was absent in the extracts of cells exposed to insulin, estrogen or progesterone and in cells treated with estrogen an additional 65 kDa band was detected which may correspond to a dimeric form of the protein. The 95 kDa band was not detected in the cultured cells. These results provide novel insights indicating that hormones have a role in the formation of the active hCTR1 protein. Furthermore, insulin altered the intracellular localisation of hCTR1, suggesting a previously undescribed role of this hormone in regulating copper uptake through the endocytic pathway.

Atomic force microscopy (AFM) is a widely used technique for characterizing the topography and frictional properties of nanostructures. Inherent misalignments between the AFM cantilever and the feedback hardware lead to crosstalk between topography data and lateral force microscopy (LFM) data. Because the degree of crosstalk depends on the positioning of the cantilever, LFM and topography data of the same structure can vary from one experiment to the next. For nanostructures with large LFM contrast, errors as large as 50% in topography and LFM can be observed. This paper describes an empirical strategy for correcting this alignment error. The technique is used to characterize the frictional properties of scanning probe-induced oxide nanostructures and the hydrogen-terminated Si(111) surfaces on which they are patterned. Reproducible differences in the frictional properties of the oxide nanostructures patterned on HF-treated and NH4F-treated Si(111) surfaces are observed and attributed to the mixed-hydride versus monohydride termination of each surface. The observed frictional contrast is consistent with known differences in surface reactivity and demonstrates how LFM measurements can provide insight into the frictional and chemical properties of nanostructures

Insulin rapidly stimulates the tyrosine kinase activity of its receptor, resulting in the phosphorylation of insulin receptor substrates (IRS), which in turn associates and activates PI 3-kinase, leading to an increase in glucose uptake. Phosphorylation of IRS proteins and activation of downstream kinases by insulin are transient and the mechanisms for the subsequent downregulation of their activity are largely unknown. We report here that the insulin-induced IRS-1 tyrosine phosphorylation and PI 3-kinase association to IRS-1 were strongly sustained by the proteasome inhibitors, MG132 and lactacystin. In contrast, no effect was detected on the insulin receptor and IRS-2 tyrosine phosphorylation. Interestingly, lactacystin also preserved PKB activation and insulin-induced glucose uptake. In contrast, calpeptin, a calpain inhibitor, was ineffective. Tyrosine phosphatase assays were also performed, showing that lactacystin was not functioning directly as a tyrosine phosphatase inhibitor "in vitro." In conclusion, proteasome inhibitors can regulate the tyrosine phosphorylation of IRS-1 and the downstream insulin signaling pathway, leading to glucose transport.

To identify cellular genes that may be involved in human papillomavirus (HPV)-mediated immortalization mRNA differential display analysis was performed on preimmortal and subsequent immortal stages of four human keratinocyte cell lines transformed by HPV type 16 or 18 DNA. This yielded a cDNA fragment encoding the transcription factor GATA-3 that was strongly reduced in intensity in all immortal stages of the four cell lines. A marked reduction in both GATA-3 mRNA and protein expression in HPV-immortalized cell lines was confirmed by reverse transcriptase-polymerase chain reaction, Western blot analysis, and immunohistochemistry and was also shown to be apparent in cervical carcinoma cell lines. Immunohistochemical analysis of cervical tissue specimens showed a clear nuclear staining for GATA-3 in normal cervical squamous epithelium (n = 14) and all cervical intraepithelial neoplasia (CIN) I (n = 6) and CIN II lesions (n = 2). In contrast, 11% (1 of 9) of CIN III lesions and 67% (8 of 12) of cervical squamous cell carcinomas revealed a complete absence of GATA-3 immunostaining. Hence, complete down-regulation of GATA-3 expression represents a rather late event during cervical carcinogenesis. Whether GATA-3 down-regulation is etiologically involved in HPV-mediated immortalization and cervical carcinogenesis remains to be examined.

In domestic pigs, litter-mates often vary considerably in birth weight. To examine whether this size variation influences piglet survival, weight gain and suckling behaviour, we experimentally manipulated the number and size distribution of litter-mates in 51 litters. Litters were small (eight or nine piglets) or large (11 or 12 piglets) compared to the herd mean of 10 piglets, and were made more or less variable in weight by using the largest and smallest quartiles of two combined litters (variable) or the middle two quartiles (uniform). Weights were measured on days 0, 3 and 21. Behavioural measures (percent of nursings missed, mean teat consistency score, per capita number of teat disputes before milk ejection, and percent time spent in teat disputes in the 20min after milk ejection) were recorded on days 1, 4, 10 and 17. Piglet weight variation (percent of coefficient of variation, CV) almost doubled over the 21 days in uniform litters and actually decreased in variable litters, but still remained higher in the variable litters. Overall, survival, percent of nursings missed, consistency in piglets' use of teats, number of teat disputes, percent time a piglet spent in teat disputes after milk ejection, and weight gain were unaffected by birth weight variation although there was a tendency (P=0.09) for more piglet deaths in variable litters. Behavioural measures of sibling competition were higher in large litters. The data provide little support for the hypotheses that high birth weight variation results in decreased survival, or that it permits rapid establishment of dominance, thereby reducing wasteful competitive behaviour in surviving piglets.

Chloroplasts in bundle sheath cells (BSC) of maize perform photosystem I (PSI)-mediated production of ATP. In this study, the participation of ascorbate (Asc) as an electron donor to PSI in light-induced electron transport in isolated maize BSC was demonstrated. It was found that Asc, at physiological concentrations, rapidly reduced photooxidized reaction center chlorophyll of PSI (P700). The rate of Asc donation of electrons to P700+ reached rates of 50-100 microequivalents (mg Chl)(-1) h(-1) at 70-80 mM ascorbate with methyl viologen as an electron acceptor. Electron transport supported by Asc was coupled with membrane energization, as demonstrated by the light-induced formation of a trans-thylakoid electric field measured by the electrochromic shift of carotenoids. The possible physiological function of Asc-dependent electron transport in bundle sheath chloroplasts of maize, as an electron donor for linear electron flow versus sustaining cyclic electron transport, is discussed.

Background: Acute renal failure (ARF) is traditionally considered a poor prognostic factor in end-stage liver disease and is associated with a mortality approaching 90%. While the increased use of orthotopic liver transplantation (OLTX) has changed the outcome for patients with end-stage liver disease (ESLD), it is not clear whether this has affected the outcome of patients with ESLD and ARF., Methods: We prospectively followed the course of ARF in 177 patients with ESLD being evaluated for OLTX. Of these patients 111 received OLTX. In-hospital mortality was compared to that of 316 ESLD patients without ARF, of these 196 received OLTX. Variables include severity of illness as assessed by APACHE II, co-morbid conditions, oliguria, need for renal replacement therapy, and etiologies of ESLD and ARF. These variables were evaluated with respect to the outcome in-hospital mortality by multiple regression analysis for patients with ARF., Results: Mortality was significantly higher in oliguric versus non-oliguric patients and in patients who required renal replacement therapy. Mortality correlated strongly with the number of co-morbid conditions, especially sepsis, encephalopathy, respiratory failure, and DIC. For OLTX recipients who developed ARF, no significant difference in survival occurred whether the ARF was pre-OLTX or post-OLTX., Conclusion: ARF was associated with an increased mortality consistent with the known adverse prognostic effect of ARF in ESLD. However, the effect of ARF on mortality was remarkably reduced in patients who received a functioning OLTX. Since expected mortality generated from APACHE II scores was higher in the ARF groups, it is not clear that there is an additional effect of ARF beyond the physiologic derangements captured by APACHE II. ARF per se should not necessarily be a contraindication to liver transplant.

Objective. To evaluate the effectiveness of spinal cord stimulation using multiple independent programmable electrode selections compared to simple continuous stimulation. Design. Prospective case series 2 years. Setting. Ambulatory care center. Patients. All chronic pain patients who underwent spinal cord stimulation treatment at our center from February 1995 until October 1996 entered the study as a consecutive sample (n = 80). Interventions. Patients were evaluated in continuous stimulation mode (single stimulation program) vs. multi-stimulation mode, (patients activate a series of stimulation programs simultaneously to cover all of their pain) and patient-controlled stimulation mode (patients can select a program in response to their activities and pain level). Outcome measures. We collected visual analog pain scores, patient satisfaction scores by stimulation mode, and paresthesia maps. Results. Mean pain scores declined from 8.1 at baseline to 4.6 with continuous stimulation, and to 3.1 with multi-stimulation and with patient-controlled stimulation (p<0.05). Paresthesia overlap improved from 74% with continuous stimulation to 91% with multi-stimulation, and to 89% with patient-controlled stimulation (p<0.05). None of the patients selected continuous stimulation. Thirty-two patients preferred multi-stimulation, and 48 patients preferred patient-controlled stimulation. Lead revision rates declined from 15% in our previous experience using continuous stimulation to 3.8%. Conclusions. Continuous stimulation was not selected by any patient in favor of multi-stimulation or patient-controlled stimulation. This study indicates that in spinal cord stimulation the use of multiple electrodes together with advanced programmability increases paresthesia overlap, reduces pain scores, reduces revision rates, and improves patient satisfaction with spinal cord stimulation therapy., (1998 Blackwell Science, Inc.)

Unlabelled: The pathogenesis of hyperlactatemia during sepsis is poorly understood. We have previously described an increase in lactate concentration across the lung in the dog during early endotoxemia. Accordingly, we sought to determine if the lung releases lactate in humans and what relation this has with lung injury., Methods: We measured lactate concentrations across the lung and lung injury scores (LIS) in two groups of patients. Group 1 consisted of nine patients with acute lung injury (LIS > or = 2.0) and elevated lactate concentrations (> 2.0 mmol/L). Group 2 contained 12 patients with no acute lung injury (LIS scores < or = 1.5), with or without increased lactate concentrations. Simultaneous measurements of plasma lactate and blood gases were obtained from indwelling arterial and pulmonary artery catheters. Measurements of cardiac output were also obtained. Lactate measurements were done using a lactate analyzer (YSI; Yellow Springs, Ohio)., Results: For each patient with acute lung injury and hyperlactatemia, an arterial-venous lactate gradient existed demonstrating release of lactate by the lung. This gradient persisted after correction for changes in hemoconcentration across the lung. The lactate gradient across the lung was 0.4 +/- 0.2 mmol/L for group 1 vs 0.05 +/- 0.1 mmol/L for group 2 (p = 0.001). This corresponded to a mean pulmonary lactate flux of 231.3 +/- 211.3 vs 5.0 +/- 37.2 mmol/h (p = 0.001). The lactate flux and the arterial-venous lactate difference correlated with LIS both for the entire sample and for the subgroup with hyperlactatemia (r = 0.69, p < 0.01). Pulmonary lactate flux was not related to arterial lactate levels (r = 0.25)., Conclusion: In patients with acute lung injury and hyperlactatemia, the lung is a major source of lactate and lactate flux correlates with LIS. This lactate flux could explain some of the hyperlactatemia seen in sepsis.

Gestational hypoglycemia may result from either reactive hypoglycemia or complications related to the pregnancy. We report a 19-year-old pregnant patient with insulinoma who was treated successfully by distal pancreatectomy during the first trimester. A high index of suspicion was required for the diagnosis since abnormal immunoreactive insulin (IRI) and glucose (G) ratios (I/G) greater than 0.3 can be found in non-insulinoma normal pregnancy. The incidence of insulinoma complicating pregnancy is unknown, but it is important since gestational hypoglycemia can be associated with an increased perinatal mortality and morbidity similar to that of gestational hyperglycemia.

Acute cerebellar ataxia has been described occasionally with infectious mononucleosis. Two additional cases are reported with serologic identification of Epstein-Barr virus (EBV) infection in blood and cerebrospinal fluid. As with previously described cases, the outcome was benign, and examination and laboratory studies did not indicate diffuse neurologic involvement. Visual and brainstem auditory-evoked responses were normal. Electroencephalograms (EEG) demonstrated 14 and 6 per second positive spikes in both patients. This pattern is considered a normal variant and has been recorded from depth electrodes and reported with deep midline lesions. These cases support the prognosis of benign cerebellar involvement in infectious mononucleosis and suggest that evidence of EBV infection be sought in patients with acute ataxia. The significance of 14/sec and 6/sec positive EEG spikes is uncertain.

An electric circuit for plant protoplast manipulation is described. The circuit used readily available materials and was designed for use in teaching. This integrated circuit can be placed in a single small box with controls for the aligning voltage, the aligning frequency, the pulse voltage, and the pulse timing. The circuit can be supplied by any suitable source of dc power and can be easily altered for individual requirements. The circuit, as presented here, can be assembled for less than $250.

The dramatic increase in use of contraception worldwide makes it imperative to understand the effects of contraceptives on the health of women using them. In this article, we review the literature on the relationships of modern nonsurgical contraception with pelvic inflammatory disease. Subsequently, we identify areas where further research is needed to better define the risks and benefits of these contraceptive methods in various settings. From our review, two new conclusions emerge. First, our reanalysis of published data on the risk of PID associated with intrauterine device (IUD) use compared with no contraceptive use shows, with one exception, less risk than the previous comparisons to all non-IUD use. Second, and probably most importantly, the studies, when taken together, strongly imply that oral contraceptives have a protective effect against PID. Only one study of 11 is equivocal on this point.

A 42-year-old man had ischemic infarction from an occlusion of the left posterior cerebral artery (PCA), but had no visual field defect by examination or Goldmann perimetry. Arteriograms showed distal filling of the occluded PCA, but no collateral blood flow from the carotid circulation, suggesting collateral flow from leptomeningeal anastomoses. Visual field sparing may occur in surgical occlusion of the PCA, but rarely occurs in stroke. An infarction from PCA occlusion is not excluded by complete visual field sparing, and studies looking for other causes of the neurologic deficit may not be necessary.

Many of the acrylic resin and bent-wire temporary partial dentures in use today produce pathologic changes in the oral mucosa. A method is outlined for the use of chrome-cobalt, instead of acrylic resin, to produce temporary prostheses. The resulting temporary partial dentures are esthetically pleasing and biologically acceptable to the oral tissues.