The effect of dietary interventions on pain and quality of life in women diagnosed with endometriosis: a prospective study with control group.

STUDY QUESTION: What is the influence of dietary interventions, namely the low fermentable oligo-, di-, mono-saccharides, and polyols (Low FODMAP) diet and endometriosis diet, on endometriosis-related pain and quality of life (QoL) compared to a control group? SUMMARY ANSWER: After adhering to a dietary intervention for 6 months, women with endometriosis reported less pain and an improved QoL compared to baseline whereas, compared to the control group, they reported less bloating and a better QoL in 3 of 11 domains. WHAT IS KNOWN ALREADY: Standard endometriosis treatment can be insufficient or may be accompanied by unacceptable side effects. This has resulted in an increasing interest in self-management strategies, including the appliance of the Low FODMAP diet and the endometriosis diet (an experience-based avoidance diet, developed by women with endometriosis). The Low FODMAP diet has previously been found effective in reducing endometriosis-related pain symptoms, whereas only limited studies are available on the efficacy of the endometriosis diet. A survey study recently found the endometriosis diet effective in improving QoL but currently no guidelines on use of the diet exist. STUDY DESIGN, SIZE, DURATION: A prospective one-center pilot study was performed between April 2021 and December 2022. Participants could choose between adherence to a diet-the Low FODMAP diet or endometriosis diet-or no diet (control group). Women adhering to a diet received extensive guidance from a dietician in training. The follow-up period was 6 months for all three groups. For all outcomes, women adhering to the diets were compared to their baseline situation and to the control group. PARTICIPANTS/MATERIALS, SETTING, METHODS: We included women diagnosed with endometriosis (surgically and/or by radiologic imaging) who reported pain scores ≥3 cm on the visual analogue score (0-10 cm) for dysmenorrhea, deep dyspareunia, and/or chronic pelvic pain. The primary endpoint focused on pain reduction for all pain symptoms, including dysuria, bloating, and tiredness. Secondary endpoints, assessed via questionnaires, focused on QoL, gastro-intestinal health, and diet adherence. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 62 participants were included in the low FODMAP diet (n = 22), endometriosis diet (n = 21), and control group (n = 19). Compared to their baseline pain scores, participants adhering to a diet reported less pain in four of six symptoms (range P < 0.001 to P = 0.012) and better scores in 6 of 11 QoL domains (range P < 0.001 to P = 0.023) after 6 months. Compared to the control group, analyzed longitudinally over the 6-month follow-up period, participants applying a diet reported significant less bloating (P = 0.049), and better scores in 3 of 11 QoL domains (range P = 0.002 to P = 0.035). LIMITATIONS, REASONS FOR CAUTION: No sample size was calculated since efficacy data were lacking in the literature. In order to optimize dietary adherence, randomization was not applied, possibly resulting in selection bias. WIDER IMPLICATIONS OF THE FINDINGS: Our study suggests that women could benefit from adherence to a dietary intervention, since we found lower pain scores and better QoL after 6 months. However, caution is implied since this is a pilot study, no sample size was calculated, and data on long-term effects (>6 months) are lacking. The results of this pilot study underline the importance of further research and the drawing up of guidelines. STUDY FUNDING/COMPETING INTEREST(S): A.v.H. reports receiving a travel grant from Merck outside the scope of this study. J.W., S.V., J.T., and B.D.B. have no conflicts of interest to report. A.d.V. reports having received KP-register points for internship guidance of J.W., performing paid consultations with endometriosis patients outside the study and receiving reimbursements for educational lectures at the local hospital (Albert Schweitzer Ziekenhuis, Dordrecht, the Netherlands). A.S. reports having received expenses for travel and hotel costs as an invited speaker from ESHRE. This was outside the scope of this study. M.v.W. reports that she is a Co-Ed of Cochrane Gynecology and Fertility. V.M. reports receiving travel and speaker's fees from Guerbet and research grants from Guerbet, Merck and Ferring. The department of reproductive medicine (V.M.) of the Amsterdam UMC, location VUmc, has received several research and educational grants from Guerbet, Merck and Ferring not related to the submitted work. TRIAL REGISTRATION NUMBER: N/A.

SOMA-trial: surgery or medication for women with an endometrioma? Study protocol for a randomised controlled trial and cohort study.

STUDY QUESTIONS: The objective of this study is to evaluate the effectiveness and cost-effectiveness of surgical treatment of women suffering from pain due to an ovarian endometrioma when compared to treatment with medication (analgesia and/or hormones). The primary outcome is defined as successful pain reduction (-30% reduction of pain) measured by the numeric rating scale (NRS) after 6 months. Secondary outcomes include successful pain reduction after 12 and 18 months, quality of life, affective symptoms, cost-effectiveness, recurrence rate, need of adjuvant medication after surgery, ovarian reserve, adjuvant surgery and budget impact. WHAT IS KNOWN ALREADY: Evidence suggests that both medication and surgical treatment of an ovarian endometrioma are effective in reducing pain and improving quality of life. However, there are no randomised studies that compare surgery to treatment with medication. STUDY DESIGN SIZE DURATION: This study will be performed in a research network of university and teaching hospitals in the Netherlands. A multicentre randomised controlled trial and parallel prospective cohort study in patients with an ovarian endometrioma, with the exclusion of patients with deep endometriosis, will be conducted. After obtaining informed consent, eligible patients will be randomly allocated to either treatment arm (medication or surgery) by using web-based block randomisation stratified per centre. A successful pain reduction is set at a 30% decrease on the NRS at 6 months after randomisation. Based on a power of 80% and an alpha of 5% and using a continuity correction, a sample size of 69 patients in each treatment arm is needed. Accounting for a drop-out rate of 25% (i.e. loss to follow up), we need to include 92 patients in each treatment arm, i.e. 184 in total. Simultaneously, a cohort study will be performed for eligible patients who are not willing to be randomised because of a distinct preference for one of the two treatment arms. We intend to include 100 women in each treatment arm to enable standardization by inverse probability weighting, which means 200 patients in total. The expected inclusion period is 24 months with a follow-up of 18 months. PARTICIPANTS/MATERIALS SETTING METHODS: Premenopausal women (age ≥ 18 years) with pain (dysmenorrhoea, pelvic pain or dyspareunia) and an ovarian endometrioma (cyst diameter ≥ 3 cm) who visit the outpatient clinic will make up the study population. Patients with signs of deep endometriosis will be excluded. The primary outcome is successful pain reduction, which is defined as a 30% decrease of pain on the NRS at 6 months after randomisation. Secondary outcomes include successful pain reduction after 12 and 18 months, quality of life and affective symptoms, cost-effectiveness (from a healthcare and societal perspective), number of participants needing additional surgery, need of adjuvant medication after surgery, ovarian reserve and recurrence rate of endometriomas. Measurements will be performed at baseline, 6 weeks and 6, 12 and 18 months after randomisation. STUDY FUNDING/COMPETING INTERESTS: This study is funded by ZonMw, a Dutch organization for Health Research and Development, project number 80-85200-98-91041. The Department of Reproductive Medicine of the Amsterdam UMC location VUmc has received several research and educational grants from Guerbet, Merck KGaA and Ferring not related to the submitted work. B.W.J. Mol is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for ObsEva, Merck KGaA and Guerbet. V. Mijatovic reports grants from Guerbet, grants from Merck and grants from Ferring outside the submitted work. All authors declare that they have no competing interests concerning this publication. TRIAL REGISTRATION NUMBER: Dutch Trial Register (NTR 7447, http://www.trialregister.nl). TRIAL REGISTRATION DATE: 2 January 2019. DATE OF FIRST PATIENT'S ENROLMENT: First inclusion in randomised controlled trial October 4, 2019. First inclusion in cohort May 22, 2019.

Macrodeformation Twins in Single-Crystal Aluminum.

Deformation twinning in pure aluminum has been considered to be a unique property of nanostructured aluminum. A lingering mystery is whether deformation twinning occurs in coarse-grained or single-crystal aluminum at scales beyond nanotwins. Here, we present the first experimental demonstration of macrodeformation twins in single-crystal aluminum formed under an ultrahigh strain rate (∼10^{6} s^{-1}) and large shear strain (200%) via dynamic equal channel angular pressing. Large-scale molecular dynamics simulations suggest that the frustration of subsonic dislocation motion leads to transonic deformation twinning. Deformation twinning is rooted in the rate dependences of dislocation motion and twinning, which are coupled, complementary processes during severe plastic deformation under ultrahigh strain rates.

Quality of life outcomes in women with endometriosis are highly influenced by recruitment strategies.

STUDY QUESTION: To what extent are outcome measures in endometriosis-related quality of life studies influenced by the setting in which patient recruitment is performed? SUMMARY ANSWER: Quality of life outcomes in women with endometriosis are highly influenced by recruitment strategies. WHAT IS KNOWN ALREADY: Most studies on quality of life in women with endometriosis are conducted in tertiary care centres or patient associations. It is conceivable that the setting in which patient recruitment is performed influences the quality of life results. This has not been investigated before. STUDY DESIGN, SIZE, DURATION: Retrospective questionnaire based cohort study (part of the World Endometriosis Research Foundation (WERF) EndoCost study). The investigated women were recruited in three settings: a tertiary care centre for endometriosis (n = 135); five secondary care centres (n = 63); an endometriosis patient association (n = 291). PARTICIPANTS/MATERIALS, SETTING, METHODS: The secondary and tertiary care population included women with a laparoscopic and/or histological diagnosis of endometriosis. The patient association population consisted of women with a self-reported diagnosis of surgically confirmed endometriosis. MAIN RESULTS AND THE ROLE OF CHANCE: The populations did not differ in terms of age, co-morbidities and education level. Delay of diagnosis was the longest in the patient association (median 7 years) (tertiary care 2 years; secondary care 1.5 years) (P < 0.001). The tertiary care population reported more laparotomies (64%) than the other populations (secondary care 43%; patient association 47%) (P = 0.002). Affected job was least prevalent in the secondary care setting (35%) (patient association 64%; tertiary care 56%) (P < 0.001). Affected relationships were most prevalent in the patient association setting (52%) (tertiary care 38%; secondary care 22%) (P < 0.001). Chronic pain was least prevalent in patients in secondary care (44%) (tertiary care 65%; patient association 61%) (P = 0.009). Substantial differences in quality of life were detected between secondary care (median physical component 50.4, mental component 49.6); tertiary care (physical component 46.2, mental component 46.2) and the patient association (physical component 45.0, mental component 44.6) (P < 0.001, P = 0.018). LIMITATIONS, REASONS FOR CAUTION: The response rate was relatively low (35%). Analysis of the hospital populations revealed that non-responders and responders did not differ with respect to age or revised American Fertility Society classification, indicating that the non-responder bias is limited. However, other factors, such as social and marital status or symptomatology, might be different for non-responders. Missing values were analysed as if the symptom was not present. Missing values never exceeded 10%, except for one value. Therefore, it can be expected that the effect of missing data on the outcome is negligible. Twenty-five patients belonged to more than one category. A sensitivity analysis showed that the influence of assigning patients to another category was limited. WIDER IMPLICATIONS OF THE FINDINGS: Outcomes regarding quality of life are highly influenced by recruitment strategy. None of the groups appeared to be a representative selection of the total population of women with endometriosis. An alternative strategy for creating a representative population for cost and quality of life studies is probably to recruit women who live in a specific geographic area rather than women that visit a specific hospital or are a member of a patient association. STUDY FUNDING/COMPETING INTERESTS: The WERF EndoCost study was funded by the World Endometriosis Research Foundation. The sponsors did not have a role in the design and conduct of this study: collection, management, analysis, interpretation of the data; preparation, review, approval of the manuscript. L.H. is the chief executive and T.M.D. was a board member of WERF at the time of funding. T.M.D holds the Merck-Serono Chair and the Ferring Chair in Reproductive Medicine in Leuven, Belgium and has served as consultant for Merck-Serono, Schering-Plough, Astellas, and Arresto. TRIAL REGISTRATION NUMBER: Not applicable.

Note: Dynamic strain field mapping with synchrotron X-ray digital image correlation.

We present a dynamic strain field mapping method based on synchrotron X-ray digital image correlation (XDIC). Synchrotron X-ray sources are advantageous for imaging with exceptional spatial and temporal resolutions, and X-ray speckles can be produced either from surface roughness or internal inhomogeneities. Combining speckled X-ray imaging with DIC allows one to map strain fields with high resolutions. Based on experiments on void growth in Al and deformation of a granular material during Kolsky bar/gas gun loading at the Advanced Photon Source beamline 32ID, we demonstrate the feasibility of dynamic XDIC. XDIC is particularly useful for dynamic, in-volume, measurements on opaque materials under high strain-rate, large, deformation.

Note: phase retrieval method for analyzing single-phase displacement interferometry data.

We present a phase retrieval method (PRM) for analyzing single-phase displacement interferometry measurements on rapidly changing velocity histories, including photon Doppler velocimetry (PDV). PRM identifies the peaks and valleys as well as zero-crossing points in a PDV time series, performs normalization and extracts point-by-point phase and thus velocity information. PRM does not require a wide time window as in sliding window Fourier transformation, and thus improves the effective temporal resolution. This method is implemented in analyzing PDV data obtained from gas gun experiments, and validated against simultaneous measurements with velocity interferometer system for any reflector.

ESHRE guideline: management of women with endometriosis.

STUDY QUESTION: What is the optimal management of women with endometriosis based on the best available evidence in the literature? SUMMARY ANSWER: Using the structured methodology of the Manual for ESHRE Guideline Development, 83 recommendations were formulated that answered the 22 key questions on optimal management of women with endometriosis. WHAT IS KNOWN ALREADY: The European Society of Human Reproduction and Embryology (ESHRE) guideline for the diagnosis and treatment of endometriosis (2005) has been a reference point for best clinical care in endometriosis for years, but this guideline was in need of updating. STUDY DESIGN, SIZE, DURATION: This guideline was produced by a group of experts in the field using the methodology of the Manual for ESHRE Guideline Development, including a thorough systematic search of the literature, quality assessment of the included papers up to January 2012 and consensus within the guideline group on all recommendations. To ensure input from women with endometriosis, a patient representative was part of the guideline development group. In addition, patient and additional clinical input was collected during the scoping and review phase of the guideline. PARTICIPANTS/MATERIALS, SETTING, METHODS: NA. MAIN RESULTS AND THE ROLE OF CHANCE: The guideline provides 83 recommendations on diagnosis of endometriosis and on the treatment of endometriosis-associated pain and infertility, on the management of women in whom the disease is found incidentally (without pain or infertility), on prevention of recurrence of disease and/or painful symptoms, on treatment of menopausal symptoms in patients with a history of endometriosis and on the possible association of endometriosis and malignancy. LIMITATIONS, REASONS FOR CAUTION: We identified several areas in care of women with endometriosis for which robust evidence is lacking. These areas were addressed by formulating good practice points (GPP), based on the expert opinion of the guideline group members. WIDER IMPLICATIONS OF THE FINDINGS: Since 32 out of the 83 recommendations for the management of women with endometriosis could not be based on high level evidence and therefore were GPP, the guideline group formulated research recommendations to guide future research with the aim of increasing the body of evidence. STUDY FUNDING/COMPETING INTEREST(S): The guideline was developed and funded by ESHRE, covering expenses associated with the guideline meetings, with the literature searches and with the implementation of the guideline. The guideline group members did not receive payment. All guideline group members disclosed any relevant conflicts of interest (see Conflicts of interest). TRIAL REGISTRATION NUMBER: NA.

Spinal gene expression profiling and pathways analysis of a CB2 agonist (MDA7)-targeted prevention of paclitaxel-induced neuropathy.

AIMS: Patients receiving paclitaxel often develop peripheral neuropathies. We found that a novel selective cannabinoid CB2 receptor agonist (MDA7) prevents paclitaxel-induced mechanical allodynia in rats and mice. Here we investigated gene expression profiling in the lumbar spinal cord after 14-day treatment of MDA7 in paclitaxel animals and analyzed possible signaling pathways underlying the preventive effect of MDA7 on paclitaxel-induced neuropathy. METHODS: Peripheral mechanical allodynia was induced in rats or mice receiving intraperitoneal (i.p.) injection of paclitaxel at a dose of 1mg/kg daily for four consecutive days. MDA7 was administered at a dose of 15mg/kg 15min before paclitaxel and then continued daily for another 10days. Whole-genome gene expression profiling in the lumbar spinal cord of MDA7 and paclitaxel-treated rats was investigated using microarray analysis. The Ingenuity pathway analysis was performed to determine the potential relevant canonical pathways responsible for the effect of MDA7 on paclitaxel-induced peripheral neuropathy. RESULTS: We observed that the inflammatory molecular networks including tumor necrosis factor (TNF), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), transforming growth factor beta (TGFß), and mitogen-activated protein kinases (MAPK) signaling are most relevant to the preventive effect of MDA7 on paclitaxel-induced peripheral neuropathy. In addition, genes encoding molecules that are important in central sensitization such as glutamate transporters and N-methyl-d-aspartate receptor 2B (NMDAR2B), and neuro-immune-related genes such as neuronal nitric oxide synthase (nNOS1), chemokine CX3CL1 (a mediator for microglial activation), toll-like receptor 2 (TLR2), and leptin were differentially modulated by MDA7. CONCLUSION: The preventive effect of MDA7 on paclitaxel-induced peripheral allodynia in rats may be associated with genes involved in signal pathways in central sensitization, microglial activation, and neuroinflammation in the spinal cord.

Molecular cloning and expression analysis of the ethylene insensitive3 (EIN3) gene in cucumber (Cucumis sativus).

The plant gaseous hormone ethylene regulates many aspects of plant growth, development, and responses to the environment. Ethylene insensitive3 (EIN3) is a key transcription factor involved in the ethylene signal transduction pathway. To gain a better understanding of this particular pathway in cucumber, the full-length cDNA encoding EIN3 (designated as CsEIN3) was cloned from cucumber for the first time by rapid amplification of cDNA ends. The full length of CsEIN3 was 2560 bp, with an open reading frame of 1908 bp encoding 635 amino acids. Sequence alignment and phylogenetic analyses revealed that CsEIN3 has high homology with other plant EIN3/EIL proteins that were derived from a common ancestor during evolution, and CsEIN3 was grouped into a cluster along with melon. Homology modeling demonstrated that CsEIN3 has a highly similar structure to the specific DNA-binding domain contained in EIN3/EIL proteins. Based on quantitative reverse transcription-polymerase chain reaction analysis, we found that CsEIN3 was constitutively expressed in all organs examined, and was increased during flower development and maturation in both male and female flowers. Our results suggest that CsEIN3 is involved in processes of flower development. In conclusion, this study will provide the basis for further study on the role of EIN3 in relevant biological processes of cucumber and on the molecular mechanism of the cucumber ethylene signaling pathway.

The ENDOCARE questionnaire (ECQ): a valid and reliable instrument to measure the patient-centeredness of endometriosis care in Europe.

BACKGROUND: Endometriosis is prevalent and women need high-quality care, which should be patient-centered. This study aimed to develop a valid and reliable patient-centeredness questionnaire, based on a defined concept of patient-centered endometriosis care (PCEC). METHODS: A literature review, focus groups (FGs) with patients and an expert panel defined PCEC with 10 dimensions. The ENDOCARE questionnaire (ECQ) was developed. FGs resulted in 43 specific statements covering the 10 dimensions of PCEC, for which the ECQ measured 'importance' and 'performance'. Medical and demographic questions and an open question were added. The Dutch ECQ questionnaire was piloted and reciprocally translated into English and Italian. Patients with endometriosis from Belgium, The Netherlands, Italy and the UK were invited to complete the ECQ online. Item analysis, inter-item analysis and confirmatory and exploratory factor analyses (EFA) and reliability analysis were performed. The theory-driven dimensions were adapted. RESULTS: The ECQ was completed by 541 patients. Based on item analysis, five statements were deleted. Factor analysis was performed on 322 questionnaires (only from respondents with a partner). Insights from the data-driven EFA suggested adaptations of the theory-driven dimensions. The reliability statistics of 9/10 adapted theory-driven dimensions were satisfactory and the root mean square error of approximation was good. CONCLUSIONS: This study resulted in a valid and reliable instrument to measure PCEC. For data presentation, the adapted theory-driven dimensions of PCEC are preferred over the data-driven factors. The ECQ may serve to benchmark patient-centeredness, conduct cross-cultural European research and set targets for improvement.

Ethanol-induced delta-opioid receptor modulation of glutamate synaptic transmission and conditioned place preference in central amygdala.

Alcoholism involves compulsive behaviors of alcohol drinking, which is thought to be related at least initially to the rewarding effect of alcohol. It has been shown that mu-opioid receptors play an essential role in drug reward and dependence for many drugs of abuse including alcohol, but the function of delta-opioid receptors (DOR) in drug reward remains largely unknown at present. Previous animal studies using systemic approaches with DOR antagonists or DOR knockout animals have yielded inconsistent results, showing a decrease, an increase or no change in alcohol consumption and behaviors of alcohol reward after DOR inhibition or deletion. In the present study, we used ethanol-conditioned rats to investigate adaptive DOR function in neurons of the central nucleus of the amygdala (CeA), a key brain site for alcohol reward and addiction. We found that functional DOR was absent in glutamate synapses of CeA neurons from control rats, but it emerged and inhibited glutamate synaptic currents in CeA neurons from rats displaying ethanol-induced behavior of conditioned place preference (CPP). Analysis of paired-pulse ratios and miniature glutamate synaptic currents revealed that the recruited DOR was present on glutamatergic presynaptic terminals. Similar induction of functional DOR was also found on GABA synapses. Furthermore, microinjection of a DOR antagonist into the CeA reversed ethanol-induced CPP behavior in rats in vivo. These results suggest that repeated alcohol exposure recruits new functional DOR on CeA glutamate and GABA synapses, which may be involved in the expression or maintenance of ethanol-induced CPP behavior.

Roles of alpha1- and alpha2-adrenoceptors in the nucleus raphe magnus in opioid analgesia and opioid abstinence-induced hyperalgesia.

Noradrenaline and alpha-adrenoceptors have been implicated in the modulation of pain in various behavioral conditions. Noradrenergic neurons and synaptic inputs are present in neuronal circuits critical for pain modulation, but their actions on neurons in those circuits and consequently the mechanisms underlying noradrenergic modulation of pain remain unclear. In this study, both recordings in vitro and behavioral analyses in vivo were used to examine cellular and behavioral actions mediated by alpha1- and alpha2-adrenoceptors on neurons in the nucleus raphe magnus. We found that alpha1- and alpha2-receptors were colocalized in the majority of a class of neurons (primary cells) that inhibit spinal pain transmission and are excited during opioid analgesia. Activation of the alpha1-receptor depolarized whereas alpha2-receptor activation hyperpolarized these neurons through a decrease and an increase, respectively, in potassium conductance. Blockade of the excitatory alpha1-receptor or activation of the inhibitory alpha2-receptor significantly attenuated the analgesia induced by local opioid application, suggesting that alpha1-receptor-mediated synaptic inputs in these primary cells contribute to their excitation during opioid analgesia. In the other cell class (secondary cells) that is thought to facilitate spinal nociception and is inhibited by analgesic opioids, only alpha1-receptors were present. Blocking the alpha1-receptor in these cells significantly reduced the hyperalgesia (increased pain) induced by opioid abstinence. Thus, state-dependent activation of alpha1-mediated synaptic inputs onto functionally distinct populations of medullary pain-modulating neurons contributes to opioid-induced analgesia and opioid withdrawal-induced hyperalgesia.

Nitric oxide inhibits GABA-evoked current in dorsal root ganglion neuron via PKG-dependent pathway.

gamma-Aminobutyric acid (GABA) is considered a major inhibitory neurotransmitter in the generation of presynaptic inhibition at central terminals of primary afferent fiber (PAF), while it has also been established that nitric oxide (NO) may sensitize the terminals of nocisponsive PAFs and enhance neuropeptide release, possibly via mechanisms involving the activation of a cyclic guanidine monophosphate (cGMP)-dependent PKG. The present work was undertaken to explore the modulatory effect of sodium nitroprusside (SNP), a donor of NO, on GABA-evoked current of isolated adult rat dorsal root ganglion (DRG) neurons and the intracellular mechanism involved, by means of whole-cell patch clamp recording. The results showed that 1 mM SNP reversibly inhibited the inward current evoked by 0.1 mM GABA (-1.05 +/- 0.17nA vs. -0.63 +/- 0.11nA, n = 22, p < 0.01 or 0.1 mM muscimol a specific GABA(A) receptor agonist (-1.70 +/- 0.39 nA vs. -1.01 +/- 0.24 nA, n = 6, p < 0.05), which could be cancelled by simultaneous application of 1 mM methylene blue, an inhibitor of PKG. After preapplication of SNP with increasing concentrations 0.03, 0.1, 0.3, 1, and 3 mM), SNP inhibited both 0.1 mM GABA-evoked current (IC(50) = 0.2423 mM, n = 5) and 0.1 mM muscimol-evoked current (IC(50) = 0.3255 mM, n = 3) in DRG neurons in a dose-dependent manner. Therefore, it was suggested that PKG-dependent pathway may be involved in the NO-induced inhibition of GABA(A) receptor-mediated inward current in rat DRG neurons, which may be involved in the presynaptic disinhibition of nociceptive information induced by NO under certain conditions.

Sympathectomy induces novel purinergic sensitivity in sciatic afferents.

AIM: To test the hypothesis that sympathectomy could induce novel purinergic sensitivity in sciatic afferents. METHODS: Teased-fiber recordings were made from 32 spontaneously active A afferents from the sciatic nerves in surgically sympathectomized rats and 30 spontaneously active A afferents from the sciatic nerves in intact rats. Adenosine 5'-triphosphate (ATP) was injected via a cannula in jugular vein. RESULTS: Twenty eight percent of the spontaneously active afferent fibers from sciatic nerves in the sympathectomized rats responded to ATP, either with an increase or with a decrease in spontaneous firing. However, none of the fibers from the sciatic nerves in the intact rats was activated by ATP. CONCLUSION: Sympathectomy induces novel purinergic sensitivity in A afferents from sciatic nerve.

Effect of D-tagatose on liver weight and glycogen content of rats.

D-tagatose is an incompletely absorbed ketohexose (stereoisomer of D-fructose) which has potential as an energy-reduced alternative sweetener. In an earlier 90-day toxicity study, rats fed diets with 10, 15 and 20% D-tagatose exhibited increased liver weights, but no histopathological alterations. To determine whether there might be any toxicological relevance to this effect, three studies were conducted in male, adult Sprague-Dawley rats. In the first study, four groups received Purina diet (group A), Purina diet with 20% D-tagatose (group B), SDS diet (group C), or SDS diet with 20% D-tagatose (group D). For groups A and B, the 28-day treatment period was followed by a 14-day recovery period (Purina diet). Food remained available to all animals until the time of sacrifice. Groups of 10 rats were killed on days 14 (groups A and B), 28 (groups A-D), and 42 (groups A and B). Body weights, as well as weights of wet and lyophilized livers, were determined. The lyophilized livers collected on day 28 from groups A and B were analyzed for protein, total lipid, glycogen, DNA, and residual moisture. By day 14, relative wet liver weights had increased by 23% in group B. On day 28, the increase was 38% in group B and 44% in group D. At the end of the recovery period, the increase had diminished to 14% in group B. On day 28, liver glycogen content (in %) was significantly increased, and liver protein, lipid, and DNA contents were significantly decreased in group B compared to group A. Total amounts per liver of protein, total lipid, glycogen, and DNA were significantly increased. In the second study, four groups of 20 rats each received SDS diet with 0, 5, 10, and 20% D-tagatose for 29-31 days. The food was available until the time of sacrifice. At termination, plasma was obtained from 10 rats/group for clinicochemical analyses. Five rats/group were subjected to whole-body perfusion, followed by processing of livers for qualitative and quantitative electron microscopic examination. Livers of 6 rats/group were analyzed for acyl-CoA oxidase and laurate 12-hydroxylase (cytochrome P450 4A1) activity, DNA synthesis (Ki-67 index), and number of nuclei per unit area of tissue. Liver weights were significantly increased in linear relation to the D-tagatose intake. Plasma transaminases (but not glutamyl transferase and alkaline phosphatase) were increased in the high-dose group. Except for glycogen accumulation, no ultrastructural changes were seen on electron microscopic examination of livers of the control and high-dose groups. Morphometric analysis confirmed the increase of glycogen and the absence of alterations of endoplasmatic reticulum, mitochondria, and Golgi apparatus. The Ki-67 index did not differ between the groups. A dose-related decrease of the number of nuclei per unit area signified some hepatocellular hypertrophy. Acyl-CoA oxidase and CYP4A1 activity were significantly increased in the mid- and high-dose groups, but these increases were small and not accompanied by electron-microscopic evidence of peroxisome proliferation. In the third study, four groups received SDS diet (groups A and C) or SDS diet with 5% D-tagatose (groups B and D). All animals were killed on day 28. Groups A and B were fasted for 24 h before sacrifice; groups C and D had food available until sacrifice. Liver weights and liver composition were measured as in Study 1. Relative wet and dry liver weights were increased in response to the treatment in rats killed under the fed condition, but not in rats killed under the fasted condition. The livers of the treated rats (group D) had an increased glycogen content in comparison to the controls (group C). Taken together, these results demonstrate that D-tagatose at dietary levels of 5-20% increases liver glycogen deposition and relative liver weights in nonfasting rats. In fasted rats the 5% dose level is the no-effect level. (ABSTRACT TRUNCATED)

[Effect of chronic hypoxia on the calcium and potassium current of myocytes of the right ventricle in guinea pig].

To explore the effect of chronic hypoxia on calcium and potassium currents of the right ventricle myocytes in the guinea pig, the cell membrane capacities, calcium and delayed rectifier potassium current were recorded using the whole-cell patch clamp technique from single right ventricle myocytes in guinea pigs under chronic hypoxia. The result demonstrated that the cell membrane capacities of the hypoxic group were larger than those of the control; between test potential of -20 mV to +20 mV, the calcium current density of the myocytes of the chronic hypoxic group was less than that of the control; the amplitude of IK of the myocytes of the chronic hypoxia group were less than that of the control group between test potential of +20 mV to +60 mV, and the IK density of the hypoxic group was also less than that of the control group between -20 mV to +60 mV. Consequently, it is suggested that chronic hypoxia may cause an increase of the membrane capacity, a decrease of the calcium current density of ventricle myocytes and a delay of the rectifier potassium current amplitude and density. All these observations provide information for the ionic basis of the attenuated contraction of cardiac muscles and prolonged action potential duration of hypoxic guinea pigs.

Disposition of 14C-erythritol in germfree and conventional rats.

The metabolism and disposition of U-14C-erythritol was examined in four groups of three male and three female, nonfasted rats each. The rats of groups A and D were germfree; the rats of groups B and C were kept under conventional conditions. The rats of group B received an erythritol-supplemented diet for 3 weeks prior to the experiment (adapted rats). The rats of groups A, C, and D were kept on an ordinary diet which was sterile for groups A and D (not adapted rats). On the day of the experiment, each rat was dosed with U-14C-erythritol by gavage (5 microCi/kg body wt; sp act 50 microCi/g erythritol). The radiochemical purity of the erythritol was 96.43% for groups A-C. Group D, which was attached to the study after evaluation of the results of groups A-C, received a more purified erythritol with a radiochemical purity of 99.46% because the data of group A pointed to a possible interference by a 14C-labeled impurity in the commercial 14C-erythritol. After dosing, respiratory CO2 and urine were collected from each rat at regular intervals for 24 hr. At termination, feces were also collected. The animals were killed and intestinal contents, organs, tissues, and the remaining carcass processed for determination of 14C-14C was excreted rapidly in the urine of all groups (range of groups A-D: 47.3-60.6% of the administered dose within the first 4 hr). Total 24-hr urinary excretion varied between 67.0% (group B) and 81.4% (group D). HPLC analysis of the urine showed that more than 96% of the eluted radiolabel represented erythritol. Conventional, adapted rats expired more 14CO2 than conventional, unadapted rats [10.9% (B) vs 6.7% (C)]. Germfree rats expired much less 14CO2 [0.8% (A) and 0.3% (D)]. In germfree rats, 14CO2 expiration started shortly after dosing, reaching half of the 24-hr excretion after about 2.5 hr. In conventional rats 14CO2 expiration started with a delay of about 2 hr reaching half the 24-hr excretion after 4-6 hr. The excretion of 14C with feces was similar in all groups (8.3% on average of all rats). Slightly more 14C was retained in the intestinal contents of germfree than conventional rats (1.9 vs 0.5%). The body retention was higher in conventional than in germfree rats (3.4 vs 2.0%). In group D, body retention was lowest (1.6%). The total recovery of 14C was similar in all groups (95.6%, average of all rats). It is concluded that ingested erythritol is efficiently absorbed mainly from the small intestine, is not metabolized to a relevant extent in the body, and is excreted unchanged in the urine. The fraction of erythritol not absorbed is fermented by the gut microflora to intermediate products which are largely absorbed and metabolized. The data support a proposed physiological energy value for erythritol of about 0.5 kcal/g.