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Enblad, Per
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Publications (10 of 59) Show all publications
Wettervik, T. S., Lenell, S., Nyholm, L., Howells, T., Lewén, A. & Enblad, P. (2018). Decompressive craniectomy in traumatic brain injury: usage and clinical outcome in a single centre. Acta Neurochirurgica, 160(2), 229-237
Open this publication in new window or tab >>Decompressive craniectomy in traumatic brain injury: usage and clinical outcome in a single centre
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2018 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 160, no 2, p. 229-237Article in journal (Refereed) Published
Abstract [en]

Background: Two randomised controlled trials (RCTs) of decompressive craniectomy (DC) in traumatic brain injury (TBI) have shown poor outcome, but there are considerations of how these protocols relate to real practice. The aims of this study were to evaluate usage and outcome of DC and thiopental in a single centre.

Method: The study included all TBI patients treated at the neurointensive care unit, Akademiska sjukhuset, Uppsala, Sweden, between 2008 and 2014. Of 609 patients aged 16 years or older, 35 treated with DC and 23 treated with thiopental only were studied in particular. Background variables, intracranial pressure (ICP) measures and global outcome were analysed.

Results: Of 35 DC patients, 9 were treated stepwise with thiopental before DC, 9 were treated stepwise with no thiopental before DC and 17 were treated primarily with DC. Six patients received thiopental after DC. For 23 patients, no DC was needed after thiopental. Eighty-eight percent of our DC patients would have qualified for the DECRA study and 38% for the Rescue-ICP trial. Favourable outcome was 44% in patients treated with thiopental before DC, 56% in patients treated with DC without prior thiopental, 29% in patients treated primarily with DC and 52% in patients treated with thiopental with no DC.

Conclusions: The place for DC in TBI management must be evaluated better, and we believe it is important that future RCTs should have clearer and less permissive ICP criteria regarding when thiopental should be followed by DC and DC followed by thiopental.

Place, publisher, year, edition, pages
SPRINGER WIEN, 2018
Keywords
Traumatic brain injury, Neurointensive care, Standardised treatment protocol, Decompressive craniectomy, Thiopental
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-341558 (URN)10.1007/s00701-017-3418-3 (DOI)000419961200003 ()29234973 (PubMedID)
Available from: 2018-02-13 Created: 2018-02-13 Last updated: 2018-02-13Bibliographically approved
Borota, L., Mahmoud, E., Nyberg, C., Lewén, A., Enblad, P. & Ronne-Engström, E. (2018). Dual lumen balloon catheter - An effective substitute for two single lumen catheters in treatment of vascular targets with challenging anatomy.. Journal of clinical neuroscience, 51, 91-99, Article ID S0967-5868(17)31621-1.
Open this publication in new window or tab >>Dual lumen balloon catheter - An effective substitute for two single lumen catheters in treatment of vascular targets with challenging anatomy.
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2018 (English)In: Journal of clinical neuroscience, ISSN 0967-5868, E-ISSN 1532-2653, Vol. 51, p. 91-99, article id S0967-5868(17)31621-1Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to describe our experience in the treatment of various pathological conditions of the cranial and spinal blood vessels and hypervascularized lesions using dual lumen balloon catheters. Twenty-five patients were treated with endovascular techniques: two with vasospasm of cerebral blood vessels caused by subarachnoid hemorrhage, one with a hypervascularized metastasis in the vertebral body, two with spinal dural fistula, four with cerebral dural fistula, three with cerebral arteriovenous malformations, and 13 with aneurysms. The dual lumen balloon catheters were used for remodeling of the coil mesh, injection of various liquid embolic agents, particles and nimodipine, for the prevention of reflux and deployment of coils and stents. The diameter of catheterized blood vessels varied from 0.7 mm to 4 mm. Two complications occurred: perforation of an aneurysm in one case and gluing of the tip of balloon catheter by embolic material in another case. All other interventions were uneventful, and therapeutic goals were achieved in all cases except in the case with gluing of the tip of balloon catheter. The balloons effectively prevented reflux regardless of the type of the embolic material and diameter of blood vessel. The results of our study show that dual lumen balloon catheters allow complex interventions in the narrow cerebral and spinal blood vessels where the safe use of two single lumen catheters is either limited or impossible.

Keywords
Balloon catheter, Dual lumen, Neurointervention
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-350827 (URN)10.1016/j.jocn.2018.01.070 (DOI)29483004 (PubMedID)
Available from: 2018-05-16 Created: 2018-05-16 Last updated: 2018-05-30Bibliographically approved
Howells, T., Smielewski, P., Donnelly, J., Czosnyka, M., Hutchinson, P. J. A., Menon, D. K., . . . Aries, M. J. H. (2018). Optimal Cerebral Perfusion Pressure in Centers With Different Treatment Protocols. Critical Care Medicine, 46(3), e235-e241
Open this publication in new window or tab >>Optimal Cerebral Perfusion Pressure in Centers With Different Treatment Protocols
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2018 (English)In: Critical Care Medicine, ISSN 0090-3493, E-ISSN 1530-0293, Vol. 46, no 3, p. e235-e241Article in journal (Refereed) Published
Abstract [en]

Objectives: The three centers in this study have different policies regarding cerebral perfusion pressure targets and use of vasopressors in traumatic brain injury patients. The aim was to determine if the different policies affected the estimation of cerebral perfusion pressure which optimizes the strength of cerebral autoregulation, termed "optimal cerebral perfusion pressure." Design: Retrospective analysis of prospectively collected data. Setting: Three neurocritical care units at university hospitals in Cambridge, United Kingdom, Groningen, the Netherlands, and Uppsala, Sweden. Patients: A total of 104 traumatic brain injury patients were included: 35 each from Cambridge and Groningen, and 34 from Uppsala. Interventions: None. Measurements and Main Results: In Groningen, the cerebral perfusion pressure target was greater than or equal to 50 and less than 70mm Hg, in Uppsala greater than or equal to 60, and in Cambridge greater than or equal to 60 or preferably greater than or equal to 70. Despite protocol differences, median cerebral perfusion pressure for each center was above 70mm Hg. Optimal cerebral perfusion pressure was calculated as previously published and implemented in the Intensive Care Monitoring+ software by the Cambridge group, now replicated in the Odin software in Uppsala. Periods with cerebral perfusion pressure above and below optimal cerebral perfusion pressure were analyzed, as were absolute difference between cerebral perfusion pressure and optimal cerebral perfusion pressure and percentage of monitoring time with a valid optimal cerebral perfusion pressure. Uppsala had the highest cerebral perfusion pressure/optimal cerebral perfusion pressure difference. Uppsala patients were older than the other centers, and age is positively correlated with cerebral perfusion pressure/optimal cerebral perfusion pressure difference. Optimal cerebral perfusion pressure was significantly lower in Groningen than in Cambridge. There were no significant differences in percentage of monitoring time with valid optimal cerebral perfusion pressure. Summary optimal cerebral perfusion pressure curves were generated for the combined patient data for each center. These summary curves could be generated for Groningen and Cambridge, but not Uppsala. The older age of the Uppsala patient cohort may explain the absence of a summary curve. Conclusions: Differences in optimal cerebral perfusion pressure calculation were found between centers due to demographics (age) and treatment (cerebral perfusion pressure targets). These factors should be considered in the design of trials to determine the efficacy of autoregulation-guided treatment.

Place, publisher, year, edition, pages
LIPPINCOTT WILLIAMS & WILKINS, 2018
Keywords
cerebral blood flow, cerebral perfusion pressure, intracranial pressure, traumatic brain injury, treatment protocols
National Category
Anesthesiology and Intensive Care
Identifiers
urn:nbn:se:uu:diva-350059 (URN)10.1097/CCM.0000000000002930 (DOI)000426301500007 ()29293154 (PubMedID)
Funder
EU, FP7, Seventh Framework Programme, 602150
Available from: 2018-05-04 Created: 2018-05-04 Last updated: 2018-05-04Bibliographically approved
Mogensen, S., Lubenow, N., Nilsson, P., Engquist, H., Knutson, F., Enblad, P., . . . Frykholm, P. (2017). An evaluation of the mixed pediatric unit for blood loss replacement in pediatric craniofacial surgery. Pediatric Anaesthesia, 27(7), 711-717
Open this publication in new window or tab >>An evaluation of the mixed pediatric unit for blood loss replacement in pediatric craniofacial surgery
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2017 (English)In: Pediatric Anaesthesia, ISSN 1155-5645, E-ISSN 1460-9592, Vol. 27, no 7, p. 711-717Article in journal (Refereed) Published
Abstract [en]

Background: Surgical correction for craniosynostosis is often associated with significant perioperative hemorrhage. We implemented a transfusion strategy with a strict protocol including transfusion triggers, frequent assessment of coagulation tests, and the use of a novel transfusion unit, the mixed pediatric unit. Aim: The aim of the study was to evaluate if the applied transfusion strategy could reduce total blood loss and number of blood donors. Methods: Children <1 year old admitted for craniosynostosis surgery were included for the study. On the day before surgery, an adult red blood cell unit was mixed with plasma and split into two mixed pediatric units-one intended for intraoperative use and the other saved for the postoperative period. A series of blood samples were obtained for standard coagulation parameters as well as thromboelastography to evaluate potential coagulopathy. Estimated blood loss, the number of additional standard packed red cell units opened in the first 24 h after surgery, the volume of fluid administered, and the total transfusion volumes were compared to a historical control group with similar age and characteristics. Results: Nineteen infants were included in the study group, and were compared to 21 historical controls. There was a significant reduction of intraoperative transfusion volume. Twelve patients were transfused postoperatively, but in 8 of these additional exposure to packed red cell donor blood was avoided by using the saved mixed pediatric unit. In the historical controls, a total of 10 packed red cell units were used in nine patients postoperatively. No additional transfusions of plasma, platelets, fibrinogen, or tranexamic acid were needed in either group, and the coagulation parameters including thromboelastography remained within their respective normal ranges in the study group. Conclusion: For craniofacial surgery in infants, moderate perioperative blood loss and avoidance of coagulopathy is possible when a multifactorial approach is implemented. In this setting, intraoperative, but not total perioperative blood loss was reduced with the studied protocol. The study indicates that there may be a role for mixed pediatric units to reduce exposure to multiple donors although the reduction in total donor exposure was not significant.

Keywords
craniosynostosis, blood loss, surgical, postoperative hemorrhage, blood transfusion, blood coagulation tests, thromboelastography, infants
National Category
Anesthesiology and Intensive Care Pediatrics
Identifiers
urn:nbn:se:uu:diva-330012 (URN)10.1111/pan.13140 (DOI)000405081500007 ()28436074 (PubMedID)
Available from: 2017-10-11 Created: 2017-10-11 Last updated: 2017-10-11Bibliographically approved
Abu Hamdeh, S., Marklund, N., Lannsjö, M., Howells, T., Raininko, R., Wikström, J. & Enblad, P. (2017). Extended anatomical grading in diffuse axonal injury using MRI: Hemorrhagic lesions in the substantia nigra and mesencephalic tegmentum indicate poor long-term outcome. Journal of Neurotrauma, 5(34), 341-352
Open this publication in new window or tab >>Extended anatomical grading in diffuse axonal injury using MRI: Hemorrhagic lesions in the substantia nigra and mesencephalic tegmentum indicate poor long-term outcome
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2017 (English)In: Journal of Neurotrauma, ISSN 0897-7151, E-ISSN 1557-9042, Vol. 5, no 34, p. 341-352Article in journal (Refereed) Published
Abstract [en]

Clinical outcome after traumatic diffuse axonal injury (DAI) is difficult to predict. In this study, three magnetic resonance imaging (MRI) sequences were used to quantify the anatomical distribution of lesions, to grade DAI according to the Adams grading system, and to evaluate the value of lesion localization in combination with clinical prognostic factors to improve outcome prediction. Thirty patients (mean 31.2 years ±14.3 standard deviation) with severe DAI (Glasgow Motor Score [GMS] <6) examined with MRI within 1 week post-injury were included. Diffusion-weighted (DW), T2*-weighted gradient echo and susceptibility-weighted (SWI) sequences were used. Extended Glasgow outcome score was assessed after 6 months. Number of DW lesions in the thalamus, basal ganglia, and internal capsule and number of SWI lesions in the mesencephalon correlated significantly with outcome in univariate analysis. Age, GMS at admission, GMS at discharge, and low proportion of good monitoring time with cerebral perfusion pressure <60 mm Hg correlated significantly with outcome in univariate analysis. Multivariate analysis revealed an independent relation with poor outcome for age (p = 0.005) and lesions in the mesencephalic region corresponding to substantia nigra and tegmentum on SWI (p  = 0.008). We conclude that higher age and lesions in substantia nigra and mesencephalic tegmentum indicate poor long-term outcome in DAI. We propose an extended MRI classification system based on four stages (stage I—hemispheric lesions, stage II—corpus callosum lesions, stage III—brainstem lesions, and stage IV—substantia nigra or mesencephalic tegmentum lesions); all are subdivided by age (≥/<30 years).

Keywords
adult brain injury, axonal injury, head trauma, MRI, susceptibility weighted imaging
National Category
Clinical Medicine Neurology
Identifiers
urn:nbn:se:uu:diva-309038 (URN)10.1089/neu.2016.4426 (DOI)000391754800009 ()27356857 (PubMedID)
Available from: 2016-12-01 Created: 2016-12-01 Last updated: 2018-02-19Bibliographically approved
Johnson, U., Engquist, H., Lewén, A., Howells, T., Nilsson, P., Ronne-Engström, E., . . . Enblad, P. (2017). Increased risk of critical CBF levels in SAH patients with actual CPP below calculated optimal CPP. Acta Neurochirurgica, 159(6), 1065-1071
Open this publication in new window or tab >>Increased risk of critical CBF levels in SAH patients with actual CPP below calculated optimal CPP
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2017 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 159, no 6, p. 1065-1071Article in journal (Refereed) Published
Abstract [en]

Background Cerebral pressure autoregulation can be quantified with the pressure reactivity index (PRx), based on the correlation between blood pressure and intracranial pressure. Using PRx optimal cerebral perfusion pressure (CPPopt) can be calculated, i.e., the level of CPP where autoregulation functions best. The relation between cerebral blood flow (CBF) and CPPopt has not been examined. The objective was to assess to which extent CPPopt can be calculated in SAH patients and to investigate CPPopt in relation to CBF.

Methods Retrospective study of prospectively collected data. CBF was measured bedside with Xenon-enhanced CT (Xe-CT). The difference between actual CPP and CPPopt was calculated (CPPa dagger). Correlations between CPPa dagger and CBF parameters were calculated with Spearman's rank order correlation coefficient (rho). Separate calculations were done using all patients (day 0-14 after onset) as well as in two subgroups (day 0-3 and day 4-14).

Results Eighty-two patients with 145 Xe-CT scans were studied. Automated calculation of CPPopt was possible in adjunct to 60% of the Xe-CT scans. Actual CPP < CPPopt was associated with higher numbers of low-flow regions (CBF < 10 ml/100 g/min) in both the early phase (day 0-3, n = 39, Spearman's rho = -0.38, p = 0.02) and late acute phase of the disease (day 4-14, n = 35, Spearman's rho = -0.39, p = 0.02). CPP level per se was not associated with CBF.

Conclusions Calculation of CPPopt is possible in a majority of patients with severe SAH. Actual CPP below CPPopt is associated with low CBF.

Keywords
cerebral blood flow, autoregulation, CPP, subarachnoid haemorrhage
National Category
Clinical Medicine
Research subject
Neurosurgery
Identifiers
urn:nbn:se:uu:diva-294191 (URN)10.1007/s00701-017-3139-7 (DOI)000401117700016 ()28361248 (PubMedID)
Available from: 2016-09-21 Created: 2016-05-18 Last updated: 2017-06-13Bibliographically approved
Vlachogiannis, P., Hillered, L., Khalil, F., Enblad, P. & Ronne, E. (2017). Interleukin-6 levels in cerebrospinal fluid and plasma in patients with severe spontaneous subarachnoid hemorrhage. Paper presented at 28th International Symposium on Cerebral Blood Flow, Metabolism and Function / 13th International Conference on Quantification of Brain Function with PET, APR 01-04, 2017, Int Soc Cerebral Blood Flow & Metab, Berlin, GERMANY. Journal of Cerebral Blood Flow and Metabolism, 37, 496-496
Open this publication in new window or tab >>Interleukin-6 levels in cerebrospinal fluid and plasma in patients with severe spontaneous subarachnoid hemorrhage
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2017 (English)In: Journal of Cerebral Blood Flow and Metabolism, ISSN 0271-678X, E-ISSN 1559-7016, Vol. 37, p. 496-496Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Sage Publications, 2017
National Category
Endocrinology and Diabetes Hematology Neurology
Identifiers
urn:nbn:se:uu:diva-331037 (URN)000400157400728 ()
Conference
28th International Symposium on Cerebral Blood Flow, Metabolism and Function / 13th International Conference on Quantification of Brain Function with PET, APR 01-04, 2017, Int Soc Cerebral Blood Flow & Metab, Berlin, GERMANY
Note

Supplement: 1, Meeting Abstract: PS06-089

Available from: 2017-10-11 Created: 2017-10-11 Last updated: 2017-10-11
Ljunghill Hedberg, A., Pauksens, K., Enblad, P., Söderberg, J., Johansson, B., Kayhty, H. & Sjölin, J. (2017). Pneumococcal polysaccharide vaccination administered early after neurotrauma or neurosurgery. Vaccine, 35(6), 909-915
Open this publication in new window or tab >>Pneumococcal polysaccharide vaccination administered early after neurotrauma or neurosurgery
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2017 (English)In: Vaccine, ISSN 0264-410X, E-ISSN 1873-2518, Vol. 35, no 6, p. 909-915Article in journal (Refereed) Published
Abstract [en]

Objectives: Pneumococcal vaccination is recommended to lower the risk of posttraumatic meningitis, and early vaccination may be of importance. After both trauma and central nervous system injury, immune suppression may occur, which could affect T-cell function and the response to T-cell dependent vaccines. We therefore aimed to investigate the response to early vaccination with a T-cell independent pneumococcal polysaccharide vaccine (PPSV). Methods: Thirty-three patients with basilar skull fracture and 23 patients undergoing transsphenoidal pituitary gland surgery were vaccinated with PPSV within 10 days after neurotrauma or neurosurgery. Twenty-nine neurosurgical patients vaccinated >= 3 weeks after neurotrauma or neurosurgery served as controls. Serotype-specific anti-polysaccharide binding IgG antibody levels to serotypes 4, 6B, 9V, 14, 18C, 19F and 23F were determined by enzyme immunoassay. Results: The vaccination was safe and a highly significant antibody response was found against all serotypes in all groups (p < 0.001 for each of the serotypes). There were no differences between groups or in the group by time interaction in any of the serotypes. After early and late vaccination, protective levels were found in >80% for serotypes 9V, 14, 18C, 19F and 23F and in 70% and 50% for serotypes 6B and 4, respectively. Conclusion: Patients vaccinated with PPSV within 10 days after neurotrauma or neurosurgery respond similarly to those vaccinated after >= 3 weeks, indicating that PPSV can be administered early after neurotrauma or neurosurgery.

Place, publisher, year, edition, pages
ELSEVIER SCI LTD, 2017
Keywords
Pneumococcal polysaccharide vaccine, Neurotrauma, Neurosurgery
National Category
Infectious Medicine Immunology in the medical area
Identifiers
urn:nbn:se:uu:diva-319568 (URN)10.1016/j.vaccine.2016.12.065 (DOI)000394196000010 ()28069358 (PubMedID)
Available from: 2017-04-06 Created: 2017-04-06 Last updated: 2018-01-13Bibliographically approved
Nyholm, L., Howells, T. & Enblad, P. (2017). Predictive Factors That May Contribute to Secondary Insults With Nursing Interventions in Adults With Traumatic Brain Injury. Journal of Neuroscience Nursing, 49(1), 49-55
Open this publication in new window or tab >>Predictive Factors That May Contribute to Secondary Insults With Nursing Interventions in Adults With Traumatic Brain Injury
2017 (English)In: Journal of Neuroscience Nursing, ISSN 0888-0395, E-ISSN 1945-2810, Vol. 49, no 1, p. 49-55Article in journal (Refereed) Published
Abstract [en]

Background: Nursing interventions pose risks and benefits to patients with traumatic brain injury at a neurointensive care unit. Objectives: The aim of this study was to investigate the risk of inducing high intracranial pressure (ICP) related to interventions and whether intracranial compliance, baseline ICP, or autoregulation could be used as predictors. Methods: The study had a quantitative, prospective, observational design. Twenty-eight patients with TBI were included, and 67 interventions were observed. The definition of a secondary ICP insult was ICP of 20 mm Hg or greater for 5 minutes or more within a continuous 10-minute period. Results: Secondary ICP insults related to nursing interventions occurred in 6 patients (21%) and 8 occasions (12%). Patients with baseline ICP of 15 mm Hg or greater had 4.7 times higher risk of developing an insult. The predictor with the best combination of sensitivity and specificity was baseline ICP. Conclusions: Baseline ICP of 15 mm Hg or greater was the most important factor to determine the risk of secondary ICP insult related to nursing intervention.

Keywords
neurointensive care, nursing implications, nursing interventions, secondary insults
National Category
Neurology Nursing
Identifiers
urn:nbn:se:uu:diva-316018 (URN)10.1097/JNN.0000000000000260 (DOI)000392410200012 ()28060220 (PubMedID)
Funder
Swedish Research Council
Available from: 2017-02-24 Created: 2017-02-24 Last updated: 2017-11-29Bibliographically approved
Rostami, E., Engquist, H., Howells, T., Ronne-Engström, E., Nilsson, P., Hillered, L. T., . . . Enblad, P. (2017). The Correlation between Cerebral Blood Flow Measured by Bedside Xenon-CT and Brain Chemistry Monitored by Microdialysis in the Acute Phase following Subarachnoid Hemorrhage. Frontiers in Neurology, 8, Article ID 369.
Open this publication in new window or tab >>The Correlation between Cerebral Blood Flow Measured by Bedside Xenon-CT and Brain Chemistry Monitored by Microdialysis in the Acute Phase following Subarachnoid Hemorrhage
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2017 (English)In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 8, article id 369Article in journal (Refereed) Published
Abstract [en]

Cerebral microdialysis (MD) may be used in patients suffering from subarachnoid hemorrhage (SAH) to detect focal cerebral ischemia. The cerebral MD catheter is usually placed in the right frontal lobe and monitors the area surrounding the catheter. This generates the concern that a fall in cerebral blood flow (CBF) and ischemic events distant to the catheter may not be detected. We aimed to investigate if there is a difference in the association between the MD parameters and CBF measured around the MD catheter compared to global cortical CBF and to CBF in the vascular territories following SAH in the early acute phase. MD catheter was placed in the right frontal lobe of 30 SAH patients, and interstitial glucose, lactate, pyruvate, glycerol, and lactate/pyruvate ratio were measured hourly. CBF measurements were performed during day 0-3 after SAH. Global cortical CBF correlated strongly with CBF around the microdialysis catheter (CBF-MD) (r = 0.911, p ≤ 0.001). This was also the case for the anterior, middle, and posterior vascular territories in the right hemisphere. A significant negative correlation was seen between lactate and CBF-MD (r = -0.468, p = 0.009). The same relationship was observed between lactate and CBF in anterior vascular territory but not in the middle and posterior vascular territories. In conclusion, global CBF 0-3 days after severe SAH correlated strongly with CBF-MD. High lactate level was associated with low global CBF and low regional CBF in the right anterior vascular territory, when the MD catheter was placed in the right frontal lobe.

Keywords
Xenon-CT, cerebral blood flow, lactate, microdialysis, subarachnoid hemorrhage
National Category
Neurosciences
Identifiers
urn:nbn:se:uu:diva-330939 (URN)10.3389/fneur.2017.00369 (DOI)000407574600001 ()28824527 (PubMedID)
Available from: 2017-10-07 Created: 2017-10-07 Last updated: 2018-01-13Bibliographically approved
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