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The β-barrel assembly machinery (BAM complex) is essential for outer membrane protein (OMP) folding in Gram-negative bacteria, and represents a promising antimicrobial target. Several conformational states of BAM have been reported, but all have been obtained under conditions which lack the unique features and complexity of the outer membrane (OM). Here, we use Pulsed Electron-Electron Double Resonance (PELDOR, or DEER) spectroscopy distance measurements to interrogate the conformational ensemble of the BAM complex in E. coli cells. We show that BAM adopts a broad ensemble of conformations in the OM, while in the presence of the antibiotic darobactin B (DAR-B), BAM's conformational equilibrium shifts to a restricted ensemble consistent with the lateral closed state. Our in-cell PELDOR findings are supported by new cryoEM structures of BAM in the presence and absence of DAR-B. This work demonstrates the utility of PELDOR to map conformational changes in BAM within its native cellular environment., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Angewandte Chemie published by Wiley-VCH GmbH.)

The folding of β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria is catalysed by the β-barrel assembly machinery (BAM). How lateral opening in the β-barrel of the major subunit BamA assists in OMP folding, and the contribution of membrane disruption to BAM catalysis remain unresolved. Here, we use an anti-BamA monoclonal antibody fragment (Fab1) and two disulphide-crosslinked BAM variants (lid-locked (LL), and POTRA-5-locked (P5L)) to dissect these roles. Despite being lethal in vivo, we show that all complexes catalyse folding in vitro, albeit less efficiently than wild-type BAM. CryoEM reveals that while Fab1 and BAM-P5L trap an open-barrel state, BAM-LL contains a mixture of closed and contorted, partially-open structures. Finally, all three complexes globally destabilise the lipid bilayer, while BamA does not, revealing that the BAM lipoproteins are required for this function. Together the results provide insights into the role of BAM structure and lipid dynamics in OMP folding.

Objective: To evaluate the efficacy of the otoprotective transtympanic application of N-acetylcysteine in preventing chemotherapy-induced ototoxicity in patients subjected to platinum-based chemotherapy. Data sources: PubMed, Scopus, Web of Science, Cochrane Central, and ClinicalTrials.gov were searched for the following concepts: (("Acetylcysteine" [Mesh]) AND ("Ototoxicity" [Mesh]) AND ("Cisplatin" [Objective: To evaluate the efficacy of otoprotective transtympanic application of N-acetylcysteine in the prevention of chemotherapy-induced ototoxicity in patients subjected to platinum-based chemotherapy. [Mesh]). Study selection: Inclusion: randomized controlled trials, Exclusion: (1) case reports or case series; (2) thesis; (3) review articles; (4) conference abstracts; (5) animal studies; (6) non-english studies; (7) studies whose population was other than patients on platinum-based chemotherapy. Data extraction: changes in hearing thresholds measured by pure tone tympanometry, covering high and low frequencies: 250, 500, 1000, 2000, 4000, and 8000 Hz. We used RevMan (Review Manager) version 5.3 to conduct the meta-analysis and GRADE to assess the quality of the evidence. Data synthesis: The literature search yielded 277 unique articles. After reviewing six full-text articles, three RCTs provided data available for meta-analysis. A total of 88 cisplatin-based chemotherapy candidates were included for final analysis. Hearing thresholds showed a significant threshold difference between the ear treated with N-acetylcysteine and the control ear (ear not treated with N-acetylcysteine), especially at high frequencies as high as 8000 Hz (pooled effect size − 10.67, 95% CI [-12.33, -9.02], P < 0.00001). The data favored the Nac group in all frequencies as well, at 4000 Hz (pooled effect size − 2.13, 95% CI [-3.49, -0.77], P = 0.002), at 2000 Hz (pooled effect size − 1.38, 95% CI [-2.69, -0.06], P = 0.04), at 1000 Hz (pooled effect size − 1.58, 95% CI [-2.63, -0.53], P = 0.003), at 500 Hz (pooled effect size − 1.58, 95% CI [-2.62, -0.54], P = 0.003), and at the low frequency of 250 after solving the heterogeneity (pooled effect size − 0.96, 95% CI [-2.88, 0.95], P = 0.32). Conclusions: Current data justifies the transtympanic administration of N-acetylcysteine for otoprotection in chemotherapy patients, minimizing the enduring consequences of cisplatin-induced ototoxicity and auditory impairment. Given the results' emphasis on the Sarafraz et al. (2018) study, more randomized controlled trials are necessary with an expanded sample size and standardization of N-acetylcysteine concentration, study population, and assessed outcomes. [ABSTRACT FROM AUTHOR]

Recent progress in the field of tactile coding suggests that discrimination of texture may involve the instantaneous kinematic analysis of frictional stick-slip movements. The idea has received support from analytical psychophysical experiments employing changes of pulsatile skin deflections in a well-adapted state, i.e. when changing repetitive pulsatile stimulation from one pulse shape to another. Here we investigated whether perception of pulse shapes is possible with single, isolated pulses. In other words, whether the well-described neuronal "onset-responses" in central parts of the tactile pathway, which differ largely from "adapted responses," carry information about pulse shape. We tested human participants on a pulse shape two-alternative forced-choice discrimination paradigm: in each trial, three pulsatile skin indentations were presented at an interval of 0.5 s. Either the first or the last pulse deviated in its shape, which the participants had to correctly identify. The task could not be solved by simply integrating tactile response across the three pulses. A majority of the participants (18 out of 30) yielded a performance of P(correct) > 0.75, indicating that isolated pulse shapes reach perception. The performance was enhanced by presenting the same shape changes in the context of a preadapting series of pulses. Participants confronted with the three-pulse test did not show a systematic preference for the kinematic parameter used to change the shape. We conclude that perceptual processes in principle have access to the kinematic shape of isolated pulsatile skin deflections. However, sensory adaption plays a crucial role in the quality and specificity of encoding kinematic pulse profiles. NEW & NOTEWORTHY: Can humans perceive the kinematic shape of very short tactile events? Textures impose such short events, frictional slips, which could be used for their discrimination. Using a pulse shape discrimination paradigm that enforces local analysis, we find that even the shape of isolated pulsatile skin deflections can be discriminated by humans. Providing an adaptive series of pulses, however, improves the performance, showing that the adaptive context plays an important role in instantaneous shape discrimination. [ABSTRACT FROM AUTHOR]

In plant-based medical systems, bitter tasting plants play a key role in managing dyspepsia. Yet when it comes to defining their mechanism of activity, herbalists and pharmacologists are split between two theories: one involves cephalic elicited vagal responses while the other comprises purely local responses. Recent studies indicate that bitters elicit a range of cephalic responses which alter postprandial gastric phase haemodynamics. Caffeine and regular coffee (Coffea arabica semen, L.) increase heart rate whereas gentian (Gentiana lutea radix, L.) and wormwood (Artemisia absinthium herba L.) increase tonus in the vascular resistance vessels. Following meals increased cardiac activity acts to support postprandial hyperaemia and maintain systemic blood pressure. The increased vascular tonus acts in parallel with the increased cardiac activity and in normal adults this additional pressor effect results in a reduced cardiac workload. The vascular response is a sympathetic reflex, evident after 5 minutes and dose dependent. Thus gentian and wormwood elicit cephalic responses which facilitate rather than stimulate digestive activity when postprandial hyperaemia is inadequate. Encapsulated caffeine elicits cardiovascular responses indicating that gastrointestinal bitter receptors are functionally active in humans. However, neither encapsulated gentian nor wormwood elicited cardiovascular responses during the gastric phase. These findings provide the platform for a new evidence-based paradigm.

Ethnopharmacological Relevance: Since Greco-Roman times bitter tastants have been used in Europe to treat digestive disorders, yet no pharmacological mechanism has been identified which can account for this practice. This study investigates whether the bitter tastants, gentian root (Gentian lutea L.) and wormwood herb (Artemisia absinthium L.), stimulate cephalic and/or gut receptors to alter postprandial haemodynamics during the gastric-phase of digestion., Materials and Methods: Normal participants ingested (1) 100 mL water plus capsules containing either cellulose (placebo-control) or 1000 mg of each tastant (n=14); or (2) 100mL of water flavoured with 500 or 1500 mg of each tastant (a) gentian (n=12) and (b) wormwood (n=12). A single beat-to-beat cardiovascular recording was obtained for the entire session. Pre/post-ingestion contrasts with the control were analysed for (1) the encapsulated tastants, in the "10 to 15" minute post-ingestion period, and (2) the flavoured water in the "5 to 10" minute post-ingestion period., Results: Water, the placebo-control, increased cardiac contraction force and blood pressure notwithstanding heart rate decreases. Encapsulated tastants did not further alter postprandial haemodynamics. In contrast gentian (500 and 1500 mg) and wormwood (1500 mg) flavoured water elicited increased peripheral vascular resistance and decreased cardiac output, primarily by reducing stroke volume rather than heart rate., Conclusions: Drinking 100mL water elicits a pressor effect during the gastric-phase of digestion due to increased cardiac contraction force. The addition of bitter tastants to water elicits an additional and parallel pressor effect due to increased peripheral vascular resistance; yet the extent of the post-prandial blood pressure increases are unchanged, presumably due to baroreflex buffering. The vascular response elicited by bitter tastants can be categorised as a sympathetically-mediated cephalic-phase response. A possible mechanism by which bitter tastants could positively influence digestion is altering gastric-phase postprandial haemodynamics and supporting postprandial hyperaemia., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Caffeine stimulates both oropharyngeal and gut bitter taste receptors (hTAS2Rs) and so has the potential to elicit reflex autonomic responses. Coffee containing 130 mg caffeine has been reported to increase heart rate for 30 min post-ingestion. Whereas added-caffeine, in doses of 25 to 200 mg, ingested with decaffeinated coffee/tea decreases heart rate 10 to 30 min post-ingestion. This study aimed to clarify caffeine's chemosensory impact. Double-espresso coffees were compared to a placebo-control capsule in a double-blind between-measures design. Coffees tested were regular coffee (130 mg caffeine) and decaffeinated coffee with added-caffeine (0, 67 and 134 mg). Cardiovascular measures from three post-ingestion phases: 1) 0 to 5; 2) 10 to 15; and 3) 25 to 30 min; were compared to pre-ingestion measures. Participants comprised 11 women in the control group and 10 women in the test group. Decaffeinated coffee elicited no changes. Decaffeinated coffee with 67 mg caffeine: decreased dp/dt in Phase 1. Decaffeinated coffee with 134 mg caffeine: increased heart rate in Phases 1 and 2; decreased spontaneous baroreflex sensitivity in Phase 1; and increased diastolic pressure in Phases 2 and 3. Regular coffee: increased heart rate in Phases 1 and 2; decreased dp/dt in all phases; and decreased systolic pressure in Phase 1. Caffeine is the substance in regular coffee which elicits chemosensory autonomic reflex responses, which involves heart activity and the baroreflex. Compared to the caffeine in regular coffee, added-caffeine elicits somewhat different chemosensory responses including a more pronounced pressor effect and resetting of the baroreflex. Caffeine in commonly consumed amounts, as well as modulating body processes by blocking adenosine receptors, can elicit reflex autonomic responses during the ingestion of caffeinated drinks. It is plausible that caffeine stimulates hTAS2Rs, during the ingestion of coffee, eliciting cephalic phase responses. These cephalic phase responses likely result from vagal withdrawal and it is uncertain whether they enhance digestion or not.

The quantity of blood arriving at the left side of the heart oscillates throughout the breathing cycle due to the mechanics of breathing. Neurally regulated fluctuations in the length of the heart period act to dampen oscillations of the left ventricular stroke volume entering the aorta. We have reported that stroke volume oscillations but not spectral frequency variability stroke volume measures can be used to estimate the breathing frequency. This study investigated with the same recordings whether heart period oscillations or spectral heart rate variability measures could function as estimators of breathing frequency. Continuous 270 s cardiovascular recordings were obtained from 22 healthy adult volunteers in the supine and upright postures. Breathing was recorded simultaneously. Breathing frequency and heart period oscillation frequency were calculated manually, while heart rate variability spectral maximums were obtained using heart rate variability software. These estimates were compared to the breathing frequency using the Bland-Altman agreement procedure. Estimates were required to be < ±10% (95% levels of agreement). The 95% levels of agreement measures for the heart period oscillation frequency (supine: -27.7 to 52.0%, upright: -37.8 to 45.9%) and the heart rate variability spectral maximum estimates (supine: -48.7 to 26.5% and -56.4 to 62.7%, upright: -37.8 to 39.3%) exceeded 10%. Multiple heart period oscillations were observed to occur during breathing cycles. Both respiratory and non-respiratory sinus arrhythmia was observed amongst healthy adults. This observation at least partly explains why heart period parameters and heart rate variability parameters are not reliable estimators of breathing frequency. In determining the validity of spectral heart rate variability measurements we suggest that it is the position of the spectral peaks and not the breathing frequency that should be the basis of decision making.

Unlabelled: The immediate and short-term chemosensory impacts of coffee and caffeine on cardiovascular activity., Introduction: Caffeine is detected by 5 of the 25 gustatory bitter taste receptors (hTAS2Rs) as well as by intestinal STC-1 cell lines. Thus there is a possibility that caffeine may elicit reflex autonomic responses via chemosensory stimulation., Methods: The cardiovascular impacts of double-espresso coffee, regular (130 mg caffeine) and decaffeinated, and encapsulated caffeine (134 mg) were compared with a placebo-control capsule. Measures of four post-ingestion phases were extracted from a continuous recording of cardiovascular parameters and contrasted with pre-ingestion measures. Participants (12 women) were seated in all but the last phase when they were standing., Results: Both coffees increased heart rate immediately after ingestion by decreasing both the diastolic interval and ejection time. The increases in heart rate following the ingestion of regular coffee extended for 30 min. Encapsulated caffeine decreased arterial compliance and increased diastolic pressure when present in the gut and later in the standing posture., Discussion: These divergent findings indicate that during ingestion the caffeine in coffee can elicit autonomic arousal via the chemosensory stimulation of the gustatory receptors which extends for at least 30 min. In contrast, encapsulated caffeine can stimulate gastrointestinal receptors and elicit vascular responses involving digestion., Conclusion: Research findings on caffeine are not directly applicable to coffee and vice versa. The increase of heart rate resulting from coffee drinking is a plausible pharmacological explanation for the observation that coffee increases risk for coronary heart disease in the hour after ingestion., (This journal is © The Royal Society of Chemistry 2011)

Caffeine users have been encouraged to consume caffeine regularly to maintain their caffeine tolerance and so avoid caffeine's acute pressor effects. In controlled conditions complete caffeine tolerance to intervention doses of 250 mg develops rapidly following several days of caffeine ingestion, nevertheless, complete tolerance is not evident for lower intervention doses. Similarly complete caffeine tolerance to 250 mg intervention doses has been demonstrated in habitual coffee and tea drinkers' but for lower intervention doses complete tolerance is not evident. This study investigated a group of habitual caffeine users following their self-determined consumption pattern involving two to six servings daily. Cardiovascular responses following the ingestion of low to moderate amounts caffeine (67, 133 and 200 mg) were compared with placebo in a double-blind, randomised design without caffeine abstinence. Pre-intervention and post-intervention (30 and 60 min) 90 s continuous cardiovascular recordings were obtained with the Finometer in both the supine and upright postures. Participants were 12 healthy habitual coffee and tea drinkers (10 female, mean age 36). Doses of 67 and 133 mg increased systolic pressure in both postures while in the upright posture diastolic pressure and aortic impedance increased while arterial compliance decreased. These vascular changes were larger upright than supine for 133 mg caffeine. Additionally 67 mg caffeine increased dp/dt and indexed peripheral resistance in the upright posture. For 200 mg caffeine there was complete caffeine tolerance. Cardiovascular responses to caffeine appear to be associated with the size of the intervention dose. Habitual tea and coffee drinking does not generate complete tolerance to caffeine as has been previously suggested. Both the type and the extent of caffeine induced cardiovascular changes were influenced by posture.

Objective: The Finometer records the beat-to-beat finger pulse contour and has been recommended for research studies assessing short-term changes of blood pressure and its variability. Variability measured in the frequency domain using spectral analysis requires the impact of breathing be restricted to high frequency spectra (>0.15 Hz) so that the data from participants need to be excluded when the breathing impact occurs in the low frequency spectra (0.04-0.15 Hz). This study tested whether breathing frequency can be estimated from standard Finometer recordings using either stroke volume oscillation frequency or spectral stroke volume variability maximum scores., Methods: Twenty-two healthy volunteers were tested for 270 s in the supine and upright positions. Finometer recorded the finger pulse contour and a respiratory transducer recorded breathing. Stoke volume oscillation frequency was calculated manually whereas the stroke volume spectral maximums were obtained using the software Cardiovascular Parameter Analysis. These estimates were compared with the breathing frequency using the Bland-Altman procedures., Results: Stroke volume oscillation frequency estimated breathing frequency to less than +/-10% and 95% levels of agreement in both supine (-7.7 to 7.0%) and upright (-6.7 to 5.4%) postures. Stroke volume variability maximum scores did not accurately estimate breathing frequency., Conclusion: Breathing frequency can be accurately derived from standard Finometer recordings using stroke volume oscillations for healthy individuals in both supine and upright postures. The Finometer can function as a standalone instrument in blood pressure variability studies and does not require support equipment to determine the breathing frequency.

Background: The clinical applicability of the Revised European-American Lymphoma (R.E.A.L.) Classification has been demonstrated in several retrospective studies. The present, ongoing study was initiated to evaluate the clinical and pathological utility of the R.E.A.L. Classification compared with the Working Formulation (WF) in a prospective fashion, in an unselected patient population treated at a single institution., Patients and Methods: Prospective data were collected on 596 biopsies from 557 patients referred with an initial diagnosis of lymphoma. After initial histologic review, 465 biopsies from 441 patients were confirmed as non-Hodgkin's lyphoma (NHL), 412 of which could be classified in R.E.A.L. and WF., Results: According to WF criteria, 25% were low grade, 58% intermediate grade and 2% high grade, 14% could not be allocated to a WF subtype. According to R.E.A.L., 46% were diffuse large B cell, 19% follicle centre lymphoma, 6% marginal zone, 6% small lymphocytic, 4% mantle cell, and 3% T-cell anaplastic large cell. For those with B-cell NHL, 7% were unclassifiable in WF compared with 1% in R.E.A.L. Corresponding figures for T-cell NHL were 68% and 3%, respectively., Conclusions: Preliminary results confirm the clinical utility of the R.E.A.L. Classification in a single institution setting, demonstrating that cases were more readily sub-typed in R.E.A.L. compared with WF. Frequencies are comparable with I.L.S.G. data. Further follow up with large patient numbers is on-going to analyse survival data with reference to clinical prognostic factors.

Background: Amyloidosis is a rare complication of non-Hodgkin's lymphoma. Most of the reported patients have had systemic amyloidosis and have died as a result of complications of this disease., Materials and Methods: The clinical cases of two patients with lymphoplasmacytic non-Hodgkin's lymphoma who presented with lymphadenopathy due to localised amyloid deposition are reviewed. Immunohistochemical studies were performed on the amyloid deposits and adjacent lymphoma., Results: The amyloid deposits in both patients were derived from monoclonal light chains of the same isotype as those expressed by the lymphoma cells and were localised to areas adjacent to the lymphoma despite the presence of circulating light chains. Both patients had an indolent clinical course and treatment appeared to have little influence on the amyloid deposition., Conclusions: Non-Hodgkin's lymphoma may be associated with localised amyloidosis secondary to local production and deposition of amyloid from monoclonal light chains synthesised by the lymphoma cells. This is a rare cause of lymphadenopathy which does not respond to treatment of the underlying lymphoma.

Background: This study was designed to evaluate the efficacy and toxicity of a 12-week alternating weekly chemotherapy regimen for advanced Hodgkin's disease. Consolidative irradiation of residual masses was used in selected cases., Patients and Methods: Eighty-three patients with newly diagnosed advanced Hodgkin's disease (bulky stage IIA, stage IIB-IVB) or with progressive disease after extended field radiotherapy for early stage disease were included in this study. The patients were treated for 12 weeks with PACE BOM comprising oral prednisolone together with intravenous doxorubicin, cyclophosphamide and etoposide alternating weekly with intravenous bleomycin, vincristine and methotrexate. Limited field adjuvant radiotherapy was also given to 21 patients with localised persistent radiological abnormalities visible on chest X-ray after chemotherapy. The study end points were overall survival, failure free survival (FFS) and toxicity, particularly with respect to reproductive function., Results: With a median post treatment follow up of 52 months the actuarial 5-year overall survival is 90% (confidence interval 81%-95%) and FFS is 64% (52%-74%). This treatment was well tolerated and fertility was maintained in a high proportion of young adults., Conclusions: The brief duration PACE BOM regimen with or without radiotherapy appears to be comparable in efficacy to other doxorubicin containing regimens, with a favourable toxicity profile. Randomised clinical trials are now needed to evaluate the role of this and comparable initial treatment approaches to advanced Hodgkin's disease.

All patients presenting with metastatic teratoma should be regarded as potentially curable and this case demonstrates the multiple treatment modalities which are often needed in the management of such patients. Increasing experience with cisplatin based combination chemotherapy has led to the development of prognostic factors which are used to determine the intensity of treatment given to individual patients. Surgical intervention plays a very important role in the management of residual disease at the completion of chemotherapy. Recognition of the growing teratoma syndrome and the importance of early surgical excision is illustrated by this case. Isolated CNS relapse may occur because the CNS may act as a sanctuary site in patients receiving systemic chemotherapy, but does not preclude long term disease free survival.

"Homing" of hematopoietic progenitor cells to the bone marrow occurs during the clinical practice of bone marrow transplantation. Its mechanism is unknown, although adhesive interactions between hematopoietic cells and sinusoidal endothelium in the bone marrow may be implicated. Studies of human bone marrow endothelial cells have previously been limited by the lack of markers for these cells. In this report, we describe positive staining of bone marrow endothelial cells from human bone marrow trephine biopsies with antibody to factor VIII-related antigen (FVIIIR-Ag) (Dako, High Wycombe, UK), the plant lectin Ulex europaeus agglutinin-I (UEA-I), and two mouse monoclonal antibodies, BMA120 and QBEND/10. In addition, alkaline phosphatase could be demonstrated in the majority of marrow endothelial cells using a novel enzyme histochemical technique. These studies defined the marker profile of human marrow endothelium. The results of this study will facilitate the isolation and culture of human marrow endothelial cells for in vitro studies of their roles in hematopoietic stem cell homing.

Background: Patients with advanced Hodgkin's disease failing to achieve complete remission with chemotherapy or developing disease progression within 1 year have a poor prognosis with salvage chemotherapy., Patients and Methods: Twenty-five patients fulfilling the above criteria after failing treatment with ChlVPP (chlorambucil, vinblastine, procarbazine and prednisolone) or its variant were treated with a new salvage regimen CAPE/PALE (cyclophosphamide, adriamycin, prednisolone, etoposide and lomustine), given for 6 courses at three weekly intervals., Results: Thirteen of the 25 patients (52%) achieved complete remission. After a minimum follow-up period of 38 months five of these patients remained free from disease progression. This regimen was very well tolerated., Conclusions: CAPE/PALE produces results comparable to other salvage regimens in Hodgkin's disease. New strategies are however required for this patient group.

27 patients with relapsed/refractory non-Hodgkin lymphoma (NHL) received combination chemotherapy with prednisolone, cytosine arabinoside, lomustine (CCNU), etoposide and thioguanine (PACET). 25 patients are evaluable for response. 7 (26%) obtained a complete response and one (4%) a partial response. The median survival for the entire group was 6 months. 2 patients are currently alive without disease, 1 of whom has received further therapy. The regimen was intensely myelosuppressive, but was well tolerated. The complete response rate and median survival figures are comparable to previous studies of salvage therapy confirming the poor prognosis for relapsed NHL and emphasising the need for prospective randomised studies.

Twelve adult patients with non-leukaemic lymphoblastic lymphoma were treated with combination chemotherapy and central nervous system prophylaxis according to the protocol developed at Stanford University. Despite strict adherence to the Stanford protocol, 4 of 12 patients relapsed in the CNS, all with meningeal disease. Only four of the 12 patients are in continuing complete remission 6 to 88 months from the completion of induction therapy. These results are inferior to those previously reported for this regimen, and fail to confirm the high rate of control of CNS disease.

High response and overall survival rates have been reported for second- and third-generation combination chemotherapy regimens used in the treatment of advanced intermediate- and high-grade non-Hodgkin's lymphoma (NHL). Results with methotrexate with leucovorin, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B) chemotherapy have been particularly impressive, although this regimen produces considerable toxicity. We have devised a similar regimen, which differs from previously reported weekly regimens in that it includes etoposide given at 14-day intervals. The doses of methotrexate and prednisolone were lower in our regimen than those used in MACOP-B. Alternating cycles of cyclophosphamide, doxorubicin, and etoposide (week 1) and methotrexate, bleomycin, and vincristine (week 2) were given for a total of 12 weeks, with continuous oral prednisolone and prophylactic antibiotics. We report here the first 61 patients entered onto this study. The overall response rate is 84% (57% complete remission [CR], 27% partial remission [PR]). With a median follow-up of 32 months for surviving patients, the actuarial overall survival at 3 years is 47%, and the failure-free survival is 45%. The dose-limiting toxicity of this regimen was mucositis. Five deaths occurred during chemotherapy, two of which were due to sepsis. The dose intensities of cyclophosphamide and doxorubicin in this regimen are considerably lower than those in MACOP-B. However, because of the inclusion of etoposide, the projected average relative dose intensity for our regimen is higher than that for MACOP-B. Our regimen has produced inferior results to those reported for MACOP-B. This may be because the addition of etoposide has failed to compensate for the lower doses of doxorubicin and cyclophosphamide. Alternatively, it may reflect differences in the presenting features of the patient populations.

Mediastinal involvement from Hodgkin's disease is common. Significant symptoms resulting from disease at this site are less common and only rarely does severe airway obstruction occur. The authors report six cases of Hodgkin's disease in which life-threatening airway obstruction was a major feature of the clinical presentation and early clinical course. The literature describing this complication is reviewed. General anesthesia with endobronchial intubation should be avoided if at all possible in patients with airway obstruction and alternative methods of diagnosis and management are discussed.

Since 1989, a Certification in Medical Oncology is offered to ESMO members on the basis of their professional curriculum vitae and of their scores in a multiple choice examination. The first session took place in London, U.K., in September 1989, during ECCO 5. One hundred and twenty-five ESMO members were evaluated by means of 60 multiple choice questions covering various aspects of medical oncology, such as tumor diagnosis, prognosis and treatment, drug pharmacology and toxicity, histology and cytology, epidemiology, carcinogenesis and tumor biology. The mean percent of correct answers was 77.4. The best results were obtained with questions dealing with chemotherapy. Scores of 40% or less were obtained in 8 questions, including 2 questions on AIDS related tumors. A similar examination is available in 1990 and will be prepared yearly in the future. It is hoped that this European ESMO Certification will contribute to lessen the professional discrepancies between oncologists of European countries and improve the level of oncological training in Europe.

1. The role of the microgeometry of planar surfaces in the detection of sliding of the surfaces on human and monkey fingerpads was investigated. By the use of a servo-controlled tactile stimulator to press and stroke glass plates on passive fingerpads of human subjects, the ability of humans to discriminate the direction of skin stretch caused by friction and to detect the sliding motion (slip) of the plates with or without micrometer-sized surface features was determined. To identify the associated peripheral neural codes, evoked responses to the same stimuli were recorded from single, low-threshold mechanoreceptive afferent fibers innervating the fingerpads of anesthetized macaque monkeys. 2. Humans could not detect the slip of a smooth glass plate on the fingerpad. However, the direction of skin stretch was perceived based on the information conveyed by the slowly adapting afferents that respond differentially to the stretch directions. Whereas the direction of skin stretch signaled the direction of impending slip, the perception of relative motion between the plate and the finger required the existence of detectable surface features. 3. Barely detectable micrometer-sized protrusions on smooth surfaces led to the detection of slip of these surfaces, because of the exclusive activation of rapidly adapting fibers of either the Meissner (RA) or the Pacinian (PC) type to specific geometries of the microfeatures. The motion of a smooth plate with a very small single raised dot (4 microns high, 550 microns diam) caused the sequential activation of neighboring RAs along the dot path, thus providing a reliable spatiotemporal code. The stroking of the plate with a fine homogeneous texture composed of a matrix of dots (1 microns high, 50 microns diam, and spaced at 100 microns center-to-center) induced vibrations in the fingerpad that activated only the PCs and resulted in an intensive code. 4. The results show that surprisingly small features on smooth surfaces are detected by humans and lead to the detection of slip of these surfaces, with the geometry of the microfeatures governing the associated neural codes. When the surface features are of sizes greater than the response thresholds of all the receptors, redundant spatiotemporal and intensive information is available for the detection of slip.

Retrospective studies have recently demonstrated a significant correlation between dose intensity of chemotherapy and response rates and survival in various diseases including epithelial ovarian carcinoma. As part of a proposed randomised trial to assess the effect of dose intensity on outcome in ovarian carcinoma, a pilot study has been undertaken to determine the toxicity and efficacy of the high intensity therapy. Nineteen patients with advanced ovarian carcinoma received initial treatment with cisplatin 120 mg m-2 i.v. day 1, and cyclophosphamide 1,000 mg-2 i.v. day 1, given at 21-day intervals for six cycles. The average relative dose intensity of this therapy is 1.14 when compared with the CHAP regimen. Severe toxicity was experienced by most patients. The median received average relative dose intensity was 0.90, with only one patient receiving treatment to the proposed intensity. Randomised studies of the effect of dose intensity in ovarian carcinoma are essential, but an initial step must be to assess whether the proposed high dose treatment can be delivered.

Protein nanopores are emerging as versatile single-molecule sensors with broad applications in DNA and protein sequencing. However, their narrow size restricts the range of detectable analytes, necessitating the development of advanced nanopores to broaden their applications in biotechnology. This review highlights a natural hetero-oligomeric porin, Nocardia farcinica porin AB (NfpAB), based on the Gram-positive mycolata, Nocardia farcinica. The pore comprises two subunits, NfpA and NfpB, that combine to form a stable structure with a unique pore geometry, asymmetrical shape, and charge distribution. Single-channel electrical recordings demonstrate that NfpAB forms stable, high-conductance channels suitable for sensing charged molecules, particularly cationic polypeptides and cyclic sugars. This pore offers advantages such as enhanced control over molecular interactions due to densely crowded charged residues, thus allowing the quantification of voltage-dependent translocation kinetics. Notably, NfpAB contains intrinsic cysteines in the pore lumen, providing an accessible site for thiol-based reactions and attachment of molecular adapters. We propose that such hetero-oligomeric pores will be effective for several applications in nanopore technology for biomolecular detection and sequencing., Competing Interests: Declarations. Conflict of interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

High-pressure and ultra-high-pressure metamorphic terrains display an internal architecture consisting of a pile (or stack) of several coherent tectonic thrust sheets or units. Their identification is fundamental for understanding the scale and mechanisms active during subduction and exhumation of these crustal slices. This study investigates the geometry of the northern Dora-Maira Massif and the kinematics of the major tectonic boundaries, combining field and geochronological data. The tectonic stack of the northern Dora-Maira Massif comprises the following units. The lowermost unit (the Pinerolo Unit) is mainly characterized by Upper Carboniferous fluvio-lacustrine (meta-)sediments. The Pinerolo unit is overthrust by a pre-Carboniferous basement. The latter is subdivided in two tectonic units (the Chasteiran and Muret Units) with different Alpine metamorphism (ultra-high-pressure and high-pressure, respectively). The pre-Carboniferous basement of the Muret Unit is thicker than previously thought for two main reasons. Firstly, some paragneisses, traditionally assumed to be Carboniferous and/or Permian in age, display detrital zircon ages indicating a main source at about 600 Ma. Secondly, three samples of the Granero Orthogneiss, previously assumed to be a Permian intrusive body, have provided zircon U–Pb ages of 447 ± 1 Ma, 456 ± 2 Ma and 440 ± 2 Ma, indicating a late Ordovician or early Silurian age for the protoliths. The uppermost unit (the Serre Unit) comprises porphyritic (meta-) volcanic and volcaniclastic rocks dated to the Permian (271 ± 2 Ma), on top of which remnants of the Mesozoic cover is preserved. Detailed mapping of an area about 140 km2 shows that (i) the ultra-high pressure Chasteiran Unit is localized at the boundary between the Pinerolo and Muret Units, (ii) the Granero Orthogneiss may be considered as the mylonitic sole of the Muret Unit, characterized by a top-to-W sense of shear, and (iii) the contact between the Muret and Serre Units displays ductile-to brittle structures (La Fracho Shear Zone), indicating a top-to-the-NW displacement of the hangingwall with respect to the footwall. A final episode of brittle faulting, cutting across the nappe stack (the Trossieri Fault), indicates an extensional stage in the core of the Alpine belt, as previously documented in more external zones. This work provides a necessary and robust basis before an accurate discussion of processes acting during continental subduction of the Dora-Maira Massif may be understood. [ABSTRACT FROM AUTHOR]

Diderm bacteria employ β‐barrel outer membrane proteins (OMPs) as their first line of communication with their environment. These OMPs are assembled efficiently in the asymmetric outer membrane by the β‐Barrel Assembly Machinery (BAM). The multi‐subunit BAM complex comprises the transmembrane OMP BamA as its functional subunit, with associated lipoproteins (e.g., BamB/C/D/E/F, RmpM) varying across phyla and performing different regulatory roles. The ability of BAM complex to recognize and fold OM β‐barrels of diverse sizes, and reproducibly execute their membrane insertion, is independent of electrochemical energy. Recent atomic structures, which captured BAM–substrate complexes, show the assembly function of BamA can be tailored, with different substrate types exhibiting different folding mechanisms. Here, we highlight common and unique features of its interactome. We discuss how this conserved protein complex has evolved the ability to effectively achieve the directed assembly of diverse OMPs of wide‐ranging sizes (8–36 β‐stranded monomers). Additionally, we discuss how darobactin—the first natural membrane protein inhibitor of Gram‐negative bacteria identified in over five decades—selectively targets and specifically inhibits BamA. We conclude by deliberating how a detailed deduction of BAM complex—associated regulation of OMP biogenesis and OM remodeling will open avenues for the identification and development of effective next‐generation therapeutics against Gram‐negative pathogens. [ABSTRACT FROM AUTHOR]

Case histories from 20 patients undergoing postchemotherapy "second look" laparotomy for metastatic epithelial cell carcinoma of the ovary were reviewed in an attempt to evaluate the usefulness of this procedure and its likely impact on patient survival. The patient population comprised 18 patients treated with a combination of cisplatin, adriamycin and cyclophosphamide (PACe) and 2 patients treated with chlorambucil. The findings at second look were often predictable, and related to the adequacy of initial surgery. Complete tumour regression identified a group of patients with a relatively good prognosis. However in most patients residual tumour was found which rarely proved resectable. Second line chemotherapy was poorly tolerated, and appeared to have little impact on the disease particularly after combination chemotherapy had been used initially. There was little evidence that second look surgery itself positively contributed to survival. This procedure and its timing should be regarded as experimental and a suitable subject for randomised clinical trials.

Bone marrow infiltrates taken from 11 patients with peripheral T cell lymphoma were immunophenotyped as T cell lymphoma using monoclonal antibodies on frozen bone marrow trephine biopsy specimens. In nine these were taken at diagnosis and in two after failure of treatment to eradicate lymphoma in the marrow. Patterns of infiltration were as follows: diffuse (n = 4), interstitial (n = 1), nodular (n = 1), focal (n = 5). All cases were CD3 positive and 10 were CD2 positive; five lacked expression of either CD5 or CD7, or both markers. In nine the determination of T cell phenotype depended on analysis of the frozen bone marrow trephine biopsy specimen as there was no other biopsy tissue available for study. In the other two cases there was agreement between the immunophenotypes seen in lymph node and bone marrow infiltrates.

Antibody to tubulin in man has been studied using a specific radioimmunoassay, affinity chromatography radioimmunoassay but markedly increased levels were noted in patients with infectious mononucleosis where the antibody was predominantly IgM in type. This finding was confirmed on fluorescence microscopy. Affinity chromatography purified antibody produced characteristic microtubular staining of fixed 3T3 cells, but in addition, produced weak staining of cryostat sections of rat tissue, similar in distribution to that of smooth muscle antibody. Our studies indicate that the IgM smooth muscle antibody found in infectious mononucleosis by IF techniques is at least in part due to an antitubulin antibody.

Two cases of Hodgkin's disease are described who relapsed 22 and 19 years after regional radiation therapy. One of the patients also developed a carcinoma of the large bowel soon after first relapse. The importance of long follow-up and documentation of cause of death in Hodgkin's disease is stressed.

Cells with the capacity for clonogenic growth in vitro can be isolated from primary human colorectal carcinomas. In this study colonies were grown, composed of cells which expressed epithelial membrane antigen and CEA, confirming their neoplastic character. Adequate growth for assessing the cytotoxicity of drugs for use in clinical chemotherapy regimes was obtained from 64% of the specimens. Colony forming efficiency of the tumour cells was not related to clinical stage or pathological grade of the parent tumour. The S-Phase fraction of the tumour was established in vitro using pulse thymidine labelling. The thymidine labelling index for Dukes' stage A and B tumours was significantly higher (median 15.7%, range 10.1-23.6%) than for Dukes' stages C and D (median 11.7%, range 0.1-13.6%). Colony forming efficiency in vitro was independent of the thymidine labelling index of the tumour. These findings are discussed with reference to the known heterogeneity of colorectal adenocarcinomas.

Eighty-one patients with germ cell tumors or ovarian carcinoma were treated over a 4-year period with cisplatin-containing combination chemotherapy. Eight patients (9.8%) experienced epileptic seizures during or within 3 months of this chemotherapy. While a definite causal relationship between the seizures and cisplatin could not be established, we have rarely seen such episodes in relationship to other cytotoxic drugs. A number of possible contributing factors were apparent, including hyponatremia and pretreatment impairment of renal function.

Eight British adults with tumours histologically and cytochemically identical to African Burkitt's lymphoma are described. In each case there was an acute clinical onset and similar tumour distribution, with involvement of the intra-abdominal organs, bone marrow and central nervous system. Jaw tumours were only present in 3 cases, and were never gross. Four patients presented as acute leukaemia. Combination chemotherapy and cranial irradiation were used to eradicate disease, but complete remissions were obtained in only 3 patients, and survival of over 1 year in only 2. The remainder died with disease present, less than 5 months from diagnosis.

Between January 1977 and January 1988, 19 patients with non-Hodgkin's lymphoma (NHL) involving the ileocaecal region were cared for by the CRC Wessex Medical Oncology Unit. Fifteen of these patients had primary ileocaecal NHL (stages IE or IIE) and four had secondary involvement of this region (stage IV). The commonest clinical presentation was with abdominal pain and a palpable mass in the right iliac fossa. Bulky (greater than 10 cm) disease was a particularly common feature, and complete surgical removal was possible in only seven patients. All patients had intermediate (18) or high grade (one) NHL using the Working Formulation. The commonest histological subtype was diffuse large cell. Seventeen patients received postoperative therapy, comprising local radiotherapy in one and combination chemotherapy in the remaining 16. Eleven of the 19 patients remain disease-free 6-60 months from diagnosis. Because of the high incidence of bulky disease at this site, postoperative therapy may be indicated, even for patients with apparently completely excised stage I disease.

This article documents the clinical course of nine patients diagnosed as having malignant histiocytosis of the intestine (MHI). Five patients had a history of gluten-sensitive enteropathy. This tumor commonly affects the small bowel in a widespread, patchy fashion causing ulceration, stricture formation, and perforation. Metastases to mesenteric nodes, liver, and the bone marrow were common. Although the diagnosis of MHI was often made at laparotomy, surgical resection, even when extensive, was not curative in any case. All nine patients were treated with a variety of chemotherapeutic regimes. This tumor proved chemosensitive, although response was usually brief and difficult to accurately evaluate. Chemotherapy was poorly tolerated because these patients were malnourished. In two cases small bowel perforation occurred, and in one gastrointestinal bleeding occurred after chemotherapy. Eight patients have died of disease from 0 to 16 months after the diagnosis was made, and a single patient is apparently cured 5+ years after completing chemotherapy. Malignant histiocytosis of the intestine has a characteristic clinical course. It is hoped that increased clinical awareness and early diagnosis will improve the outcome.

Eighty-six consecutive untreated adults with acute myelogenous leukemia were treated with a combination of Adriamycin, vincristine, prednisolone, Cytosine Arabinoside, and BCG. Complete remission was achieved in 39 (45%) patients; these patients were then allocated on an alternate basis to receive BCG and monthly chemotherapy with or without weekly irradiated allogeneic blast cells. The median duration of remission was eight months and was the same for both groups. The median survival of those achieving complete remission was 19 months compared with two months for those not achieving complete remission. Nine patients are still alive without relapse and five of these patients have been disease free for more than three years.

Three patients with acute lymphoblastic leukaemia are reported in whom Hodgkin's disease developed during chemotherapy-maintained remission. This association has been reported only once before. The pathogenesis of the Hodgkin's disease in these patients is discussed, including the possible role of anti-leukaemic therapy.

The clinical efficacy of antiemetic drugs was tested in cancer patients who were given a placebo and two antiemetic drugs alone and in combination according to random sequences. The method of investigation allowed assessment of the antiemetic effect and side effects of each drug or combination of drugs using a minimum number of patients. The trial design takes into account carry-over effects and biased selection and is potentially useful in the study of drug side effects. Fifteen patients received cyclizine, metoclopramide, cyclizine and metoclopramide, or placebo in a random sequence without evidence that the drugs tested were better than the placebo. A combination of Nabilone and metoclopramide was used in an unrandomized pilot study (prior to the withdrawal of Nabilone from clinical use); these patients recorded better scores for nausea and vomiting and patient acceptability than those in the randomized study. Present antiemetics remain inadequate and although cannabinol derivatives show an improved antiemetic effect, they cause moderate side effects themselves.