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1.
PLoS One ; 19(6): e0304184, 2024.
Article in English | MEDLINE | ID: mdl-38875269

ABSTRACT

Vestibular schwannoma can cause vestibular dysfunction; however, conflicting evidence exists regarding whether this affects the incidence of fall-related injuries in this patient population. This matched cross-sectional and cohort study assess the risk of fall-related injuries in patients with vestibular schwannoma. The study included patients with vestibular schwannoma treated at a tertiary referral hospital in Sweden between 1988 and 2014. Information on fall-related injuries was obtained from the National Patient Register, and matched population comparisons were randomly selected in a 1:25 ratio. Fall-related injuries occurring pre- (within 5 years before the diagnosis of vestibular schwannoma) and post-diagnostically (up to 3 years after diagnosis or intervention) were registered. The association between vestibular schwannoma and fall-related injuries was estimated using logistic regression and Cox proportional hazards analyses. We identified 1153 patients with vestibular schwannoma (569 [49%] women and 584 [51%] men), and 28815 population comparisons. Among the patients, 9% and 7% had pre- and post-diagnostic fall-related injuries, respectively, and among the comparisons, 8% and 6% had pre- and post-diagnostic fall-related injuries, respectively. There was no increased risk of pre- (OR 1.14; CI 0.92-1.41) or post-diagnostic 1 year (HR 1.16; CI 0.87-1.54) or 3 years (HR 1.11; CI 0.89-1.29) fall-related injury among the total patient cohort. In age-stratified analyses, we found an increased risk of pre-diagnostic fall-related injury among patients aged 50-69 years (OR 1.42; CI 1.10-1.88). Patients who underwent middle fossa surgery, regardless of age, had an increased risk of post-surgery fall-related injury within 3 years of follow-up (HR 2.68; CI 1.06-6.81). We conclude that patients with vestibular schwannoma have a low risk of enduring fall-related injuries. Middle-aged patients with dizziness and fall-related injuries should be considered for a vestibular clinical evaluation. Our results highlight the importance of rehabilitation in avoiding future fall-related injuries among patients undergoing middle fossa surgery.


Subject(s)
Accidental Falls , Neuroma, Acoustic , Humans , Neuroma, Acoustic/epidemiology , Neuroma, Acoustic/complications , Female , Male , Middle Aged , Aged , Accidental Falls/statistics & numerical data , Sweden/epidemiology , Adult , Cross-Sectional Studies , Risk Factors , Cohort Studies
2.
Sci Rep ; 14(1): 14118, 2024 06 19.
Article in English | MEDLINE | ID: mdl-38898156

ABSTRACT

This study examined the association between hearing loss in sporadic vestibular schwannoma patients and the proteome of perilymph (PL), cerebrospinal fluid (CSF), and vestibular schwannoma. Intraoperative sampling of PL and of CSF, and biopsy of vestibular schwannoma tissue, was performed in 32, 32, and 20 patients with vestibular schwannoma, respectively. Perilymph and CSF in three patients with meningioma and normal hearing were also sampled. The proteomes were identified by liquid chromatography coupled to high-resolution tandem mass spectrometry. Preoperative hearing function of the patients was evaluated with pure tone audiometry, with mean values at frequencies of 500, 1000, 2000, and 4000 Hz (PTA4) in the tumor-affected ear used to delineate three hearing groups. Analysis of the PL samples revealed significant upregulation of complement factor H-related protein 2 (CFHR2) in patients with severe to profound hearing loss after false discovery rate correction. Pathway analysis of biofunctions revealed higher activation scores in the severe/profound hearing loss group of leukocyte migration, viral infection, and migration of cells in PL. Upregulation of CFHR2 and activation of these pathways indicate chronic inflammation in the cochlea of vestibular schwannoma patients with severe to profound hearing loss compared with patients with normal hearing or mild hearing loss.


Subject(s)
Hearing Loss , Neuroma, Acoustic , Perilymph , Proteome , Humans , Neuroma, Acoustic/cerebrospinal fluid , Neuroma, Acoustic/metabolism , Neuroma, Acoustic/pathology , Female , Male , Middle Aged , Perilymph/metabolism , Hearing Loss/cerebrospinal fluid , Adult , Aged , Cerebrospinal Fluid/metabolism , Audiometry, Pure-Tone
3.
Acta Otolaryngol ; 143(8): 662-668, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37665077

ABSTRACT

BACKGROUND: Cholesteatoma is a formation of epithelium mass in the middle ear. Surgery aims to prevent complications while maintain or improve hearing. AIMS/OBJECTIVES: To determine if waiting time until cholesteatoma surgery affects hearing outcome and patients' satisfaction. MATERIAL AND METHODS: A retrospective cohort study performed at the only Ear Nose Throat clinic in one county in Sweden. Sixty concomitant surgeries, both first time and revisions, were included. RESULTS: Of the 60 surgeries, 33 (55%) were performed within a 3-month period. The mean waiting time was 1.4 months. In the remaining 27 cases, the mean waiting time was 8.6 months. Both groups had preoperatively similar air conduction pure tone average (AC PTA4), 47.3 dB and 47.0 dB respectively. The mean AC PTA4 gain was greater in the group with waiting time ≤3 months (8.6 dB) compared to the >3 months group (1.2 dB, p = 0.040). The patients' satisfaction was lower in the latter group, but the difference was not statistically significant. CONCLUSIONS: This study indicates that longer waiting time to cholesteatoma surgery has a negative impact on postoperative hearing results but not on patients' satisfaction. SIGNIFICANCE: The outcome of this study suggests that waiting time to surgery can be a factor determining postoperative hearing results.


Subject(s)
Cholesteatoma , Patient Satisfaction , Humans , Retrospective Studies , Waiting Lists , Hearing
4.
Clin Otolaryngol ; 48(6): 895-901, 2023 11.
Article in English | MEDLINE | ID: mdl-37555629

ABSTRACT

OBJECTIVES: To investigate if prophylactic antibiotics (PA) in conjunction with myringoplasty of clean and uninfected ears entails a reduction of postoperative infections within 6 weeks after surgery, and whether it affects the healing rate of the tympanic membrane (TM) at follow-up, 6-24 months after surgery. DESIGN: A retrospective cohort study of prospectively collected data. SETTING: Data extracted from The Swedish Quality Register for Ear Surgery (SwedEar), the years 2013-2019. PARTICIPANTS: All patients in SwedEar with a registered clean conventional myringoplasty (tympanoplasty type I) including a follow-up visit. MAIN OUTCOME MEASURES: The effect of PA use on TM healing rate at follow-up and postoperative infection within 6 weeks of surgery. RESULTS: In the study group (n = 1665) 86.2% had a healed TM at follow-up. There was no significant difference between the groups that had PA administered (87.2%) or not (86.1%). A total of 8.0% had a postoperative infection within 6 weeks. Postoperative infection occurred in 10.2% of the group that received PA (n = 187) compared with 7.7% of the group that did not receive PA. However, this difference was not statistically significant. Postoperative infection within 6 weeks significantly lowered the frequency of healed TMs. CONCLUSION: PA administered during clean conventional myringoplasty does not improve the chance of having a healed TM at follow up, nor decrease the risk of having a postoperative infection within 6 weeks after surgery.


Subject(s)
Anti-Bacterial Agents , Myringoplasty , Surgical Wound Infection , Tympanic Membrane Perforation , Tympanic Membrane , Wound Healing , Humans , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis/statistics & numerical data , Cohort Studies , Myringoplasty/adverse effects , Myringoplasty/statistics & numerical data , Registries/statistics & numerical data , Retrospective Studies , Sweden/epidemiology , Treatment Outcome , Tympanic Membrane Perforation/drug therapy , Tympanic Membrane Perforation/epidemiology , Tympanic Membrane Perforation/surgery , Tympanic Membrane/drug effects , Tympanic Membrane/injuries , Tympanic Membrane/surgery , Follow-Up Studies , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiology , Surgical Wound Infection/prevention & control , Wound Healing/drug effects
5.
JAMA Otolaryngol Head Neck Surg ; 149(5): 390-396, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36929420

ABSTRACT

Importance: Cholesteatoma in the middle ear is not regarded as a hereditary disease, but case reports of familial clustering exist in the literature, as well as observed familial cases in the clinical work. However, the knowledge regarding cholesteatoma as a hereditary disease is lacking in the literature. Objective: To assess the risk of cholesteatoma in individuals with a first-degree relative surgically treated for the same disease. Design, Setting, and Participants: In this nested case-control study in the Swedish population between 1987 and 2018 of first-time cholesteatoma surgery identified from the Swedish National Patient Register, 2 controls per case were randomly selected from the population register through incidence density sampling, and all first-degree relatives for cases and controls were identified. Data were received in April 2022, and analyses were conducted between April and September 2022. Exposure: Cholesteatoma surgery in a first-degree relative. Main Outcomes and Measures: The main outcome was first-time cholesteatoma surgery. The association between having a first-degree relative with cholesteatoma and the risk of cholesteatoma surgery in the index persons was estimated by odds ratios (ORs) and 95% CIs through conditional logistic regression analysis. Results: Between 1987 and 2018, 10 618 individuals with a first-time cholesteatoma surgery (mean [SD] age at surgery, 35.6 [21.5] years; 6302 [59.4%] men) were identified in the Swedish National Patient Register. The risk of having a cholesteatoma surgery was almost 4 times higher in individuals having a first-degree relative surgically treated for the disease (OR, 3.9; 95% CI, 3.1-4.8), but few cases were exposed overall. Among the 10 105 cases with at least 1 control included in the main analysis, 227 (2.2%) had at least 1 first-degree relative treated for cholesteatoma, while the corresponding numbers for controls were 118 of 19 553 control patients (0.6%). The association was stronger for individuals under the age of 20 years at first surgery (OR, 5.2; 95% CI, 3.6-7.6) and for a surgery involving the atticus and/or mastoid region (OR, 4.8; 95% CI, 3.4-6.2). There was no difference in the prevalence of having a partner with cholesteatoma between cases and controls (10 cases [0.3%] and 16 controls [0.3%]; OR, 0.92; 95% CI, 0.41-2.05), which implies that increased awareness does not explain the association. Conclusions and Relevance: In this Swedish case-control study using nationwide register data with high coverage and completeness, the findings suggest that the risk of cholesteatoma in the middle ear is strongly associated with a family history of the condition. Family history was nevertheless quite rare and can therefore only explain a limited number of all cases; these families could be an important source for information regarding the genetic background for cholesteatoma disease.


Subject(s)
Cholesteatoma, Middle Ear , Cholesteatoma , Male , Humans , Young Adult , Adult , Female , Case-Control Studies , Cholesteatoma/epidemiology , Ear, Middle , Incidence , Sweden/epidemiology , Cholesteatoma, Middle Ear/epidemiology , Cholesteatoma, Middle Ear/genetics , Cholesteatoma, Middle Ear/surgery
6.
World Neurosurg ; 175: e344-e351, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36966914

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the association between intraoperative intrasellar pressure (ISP) and pre- and postoperative endocrine disturbances with focus on hyperprolactinemia and hypopituitarism in patients with pituitary tumors. METHODS: The study is a consecutive, retrospective study with ISP collected prospectively. One hundred patients operated with transsphenoidal surgery due to a pituitary tumor, who had their ISP measured intraoperatively, were included. Data on patient endocrine status preoperatively and from 3-month postoperative follow-up were collected from medical records. RESULTS: The risk of preoperative hyperprolactinemia in patients with nonprolactinoma pituitary tumors increased with ISP (unit odds ratio 1.067, n = 70) (P = 0.041). Preoperative hyperprolactinemia was normalized at 3 months after surgery. Mean ISP was higher in patients with preoperative thyroid-stimulating hormone (TSH) deficiency (25.3 ± 9.2 mmHg, n = 37) than in patients with intact thyroid axis (21.6 ± 7.2 mmHg, n = 50) (P = 0.041). No significant difference in ISP was found between patients with and without adrenocorticotropic hormone(ACTH) deficiency. No association was found between ISP and postoperative hypopituitarism at 3 months after surgery. CONCLUSIONS: In patients with pituitary tumors, preoperative hypothyroidism and hyperprolactinemia may be associated with higher ISP. This is in line with the theory of pituitary stalk compression, suggested to be mediated by an elevated ISP. ISP does not predict the risk of postoperative hypopituitarism 3 months after surgical treatment.


Subject(s)
Adenoma , Hyperprolactinemia , Hypopituitarism , Hypothyroidism , Pituitary Neoplasms , Humans , Pituitary Neoplasms/complications , Pituitary Neoplasms/surgery , Pituitary Neoplasms/pathology , Hyperprolactinemia/etiology , Retrospective Studies , Adenoma/surgery , Hypopituitarism/complications , Hypothyroidism/complications , Adrenocorticotropic Hormone
7.
RSC Med Chem ; 13(9): 1052-1057, 2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36324499

ABSTRACT

Fragment based drug discovery is a critical part of the lead generation toolbox and relies heavily on a readily available, high quality fragment library. Over years of use, the AstraZeneca fragment set had become partially depleted and instances of compound deterioration had been found. It was recognised that a redevelopment was required. This provided an opportunity to evolve our screening sets strategy, whilst ensuring that the quality of the fragment set met the robust requirements of fragment screening campaigns. In this communication we share the strategy employed, in particular highlighting two aspects of our approach that we believe others in the community would benefit from, namely that; (i) fragments were selected with input from Medicinal Chemists at an early stage, and (ii) the library was arranged in a layered format to ensure maximum flexibility on a per target basis.

8.
Ann N Y Acad Sci ; 1514(1): 132-141, 2022 08.
Article in English | MEDLINE | ID: mdl-35580981

ABSTRACT

Short bowel syndrome can occur after extensive intestinal resection, causing intestinal insufficiency or intestinal failure, which requires long-term parenteral nutrition. Glucagon-like peptide-2 (GLP-2) pharmacotherapy is now clinically used to reduce the disease burden of intestinal failure. However, many patients still cannot be weaned off from parenteral nutrition completely. The novel dual GLP-1 and GLP-2 receptor agonist dapiglutide has previously been shown to be highly effective in a preclinical murine short bowel model. Here, we studied the effects of dapiglutide on intestinal epithelial barrier function. In the jejunum, dapiglutide increased claudin-7 expression and tightened the paracellular tight junction leak pathway. At the same time, dapiglutide promoted paracellular tight junction cation size selectivity in the jejunum. This was paralleled by extension of the cation selective tight junction proteins claudin-2 and claudin-10b and preserved claudin-15 expression and localization along the crypt-villus axis in the jejunum. In the colon, no barrier effects from dapiglutide were observed. In the colon, dapiglutide attenuated the short bowel-associated, compensatorily increased epithelial sodium channel activity, likely secondary, by improved volume status. Future studies are needed to address the intestinal adaptation of the colon.


Subject(s)
Glucagon-Like Peptide 1 , Short Bowel Syndrome , Animals , Claudins/metabolism , Glucagon-Like Peptide 1/metabolism , Glucagon-Like Peptide 2/metabolism , Glucagon-Like Peptide 2/pharmacology , Glucagon-Like Peptide-2 Receptor/metabolism , Humans , Intestinal Mucosa/metabolism , Mice , Short Bowel Syndrome/drug therapy , Short Bowel Syndrome/metabolism
9.
Front Mol Neurosci ; 15: 842132, 2022.
Article in English | MEDLINE | ID: mdl-35392272

ABSTRACT

Background: Furosemide is a loop diuretic used to treat edema; however, it also targets the Na-K-Cl cotransporter-1 (NKCC1) in the inner ear. In very high doses, furosemide abolishes the endocochlear potential (EP). The aim of the study was to gain a deeper understanding of the temporal course of the acute effects of furosemide in the inner ear, including the protein localization of Fetuin-A and PEDF in guinea pig cochleae. Material and Method: Adult guinea pigs were given an intravenous injection of furosemide in a dose of 100 mg per kg of body weight. The cochleae were studied using immunohistochemistry in controls and at four intervals: 3 min, 30 min, 60 min and 120 min. Also, cochleae of untreated guinea pigs were tested for Fetuin-A and PEDF mRNA using RNAscope® technology. Results: At 3 min, NKCC1 staining was abolished in the type II fibrocytes in the spiral ligament, followed by a recovery period of up to 120 min. In the stria vascularis, the lowest staining intensity of NKCC1 presented after 30 min. The spiral ganglion showed a stable staining intensity for the full 120 min. Fetuin-A protein and mRNA were detected in the spiral ganglion type I neurons, inner and outer hair cells, pillar cells, Deiters cells and the stria vascularis. Furosemide induced an increased staining intensity of Fetuin-A at 120 min. PEDF protein and mRNA were found in the spiral ganglia type I neurons, the stria vascularis, and in type I and type II fibrocytes of the spiral ligament. PEDF protein staining intensity was high in the pillar cells in the organ of Corti. Furosemide induced an increased staining intensity of PEDF in type I neurons and pillar cells after 120 min. Conclusion: The results indicate rapid furosemide-induced changes of NKCC1 in the type II fibrocytes. This could be part of the mechanism that causes reduction of the EP within minutes after high dose furosemide injection. Fetuin-A and PEDF are present in many cells of the cochlea and probably increase after furosemide exposure, possibly as an otoprotective response.

10.
BMC Neurol ; 22(1): 82, 2022 Mar 09.
Article in English | MEDLINE | ID: mdl-35264140

ABSTRACT

BACKGROUND: Only a few earlier publications on intrasellar pressure (ISP) have not been able to fully clarify any association between ISP and pituitary adenoma size and growth pattern. The aim of the study was to determine if intrasellar pressure (ISP) is elevated in patients with pituitary adenoma, and if the pressure is associated with tumour size and growth pattern. METHODS: The study included 100 patients operated for suspected pituitary adenoma, who have had their ISP measured intraoperatively. All adenomas were classified on the basis of Knosp and SIPAP, from which further classification of invasiveness was performed. MRT examinations were used to calculate the tumour volume and diameter in three axes. RESULTS: After exclusions, 93 cases were analysed. The mean ISP was 23.0 ± 8.4 mmHg. There were positive correlations between ISP and tumour volume and tumour diameters along all three axes. Coronal tumour diameter showed the strongest correlation with ISP elevation in a multivariate effect test. Adenomas classified as parasellar invasive (Knosp grade 3-4) showed higher mean ISP than adenomas considered as non-invasive (Knosp 0-2). CONCLUSIONS: ISP is affected by tumour anatomy and correlates positively with tumour volume. Tumour width, i.e. diameter in the coronal plane, appears to be the measure that most strongly affects the ISP. This is confirmed by the association between ISP elevation and parasellar growth.


Subject(s)
Adenoma , Pituitary Neoplasms , Adenoma/surgery , Humans , Pituitary Neoplasms/complications , Pituitary Neoplasms/surgery
11.
JPEN J Parenter Enteral Nutr ; 46(5): 1107-1118, 2022 07.
Article in English | MEDLINE | ID: mdl-34705281

ABSTRACT

BACKGROUND: Extensive intestinal resection may lead to short bowel (SB) syndrome, resulting in intestinal insufficiency or intestinal failure (IF). Intestinal insufficiency and IF involve deficiency of the proglucagon-derived hormones glucagon-like peptide-1 (GLP-1) and GLP-2. Two major problems of SB are epithelial surface loss and accelerated transit. Standard treatment now targets intestinal adaptation with a GLP-2 analogue to enlarge absorptive surface area. It is possible that additional benefit can be gained from a combination of GLP-1 and GLP-2 activity, with the aim to enlarge intestinal surface area and slow intestinal transit. METHODS: The GLP-1- and GLP-2-specific effects of the novel dual GLP-1 receptor (GLP-1R) and GLP-2 receptor (GLP-2R) agonist dapiglutide (rINN) were characterized in rodents. Furthermore, in a murine SB model of intestinal insufficiency with 40% ileocecal resection, the influence of dapiglutide on intestinal growth, body weight, food intake, volume status, and stool water content was tested against vehicle and sham-operated male mice. RESULTS: Dapiglutide significantly improves oral glucose tolerance, reduces intestinal transit time, and promotes intestinal growth. In the SB mouse model, dapiglutide promotes body weight recovery, despite unchanged intake of liquid diet. Dapiglutide promotes significant intestinal growth, as indicated by significantly increased villus height as well as intestinal length. Furthermore, dapiglutide reduces stool water losses, resulting in reduced plasma aldosterone. CONCLUSION: Dapiglutide possesses specific and potent GLP-1R and GLP-2R agonist effects in rodents. In the murine SB model, combined unimolecular GLP-1R and GLP-2R stimulation with dapiglutide potently attenuates intestinal insufficiency and potentially also IF.


Subject(s)
Glucagon-Like Peptide 1 , Short Bowel Syndrome , Animals , Body Weight/physiology , Disease Models, Animal , Glucagon-Like Peptide 2/pharmacology , Glucagon-Like Peptide-2 Receptor , Male , Mice , Short Bowel Syndrome/drug therapy , Water
12.
Sci Rep ; 11(1): 11850, 2021 06 04.
Article in English | MEDLINE | ID: mdl-34088924

ABSTRACT

The endolymphatic sac (ES) is the third part of the inner ear, along with the cochlea and vestibular apparatus. A refined sampling technique was developed to analyse the proteomics of ES endolymph. With a tailored solid phase micro-extraction probe, five ES endolymph samples were collected, and six sac tissue biopsies were obtained in patients undergoing trans-labyrinthine surgery for sporadic vestibular schwannoma. The samples were analysed using nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS) to identify the total number of proteins. Pathway identification regarding molecular function and protein class was presented. A total of 1656 non-redundant proteins were identified, with 1211 proteins detected in the ES endolymph. A total of 110 proteins were unique to the ES endolymph. The results from the study both validate a strategy for in vivo and in situ human sampling during surgery and may also form a platform for further investigations to better understand the function of this intriguing part of the inner ear.


Subject(s)
Endolymph/metabolism , Endolymphatic Sac/metabolism , Neuroma, Acoustic/metabolism , Proteome/metabolism , Adult , Aged , Animals , Biopsy , Chromatography, Liquid , Cochlea , Ear, Inner/physiology , Female , Humans , Male , Mass Spectrometry , Middle Aged , Tandem Mass Spectrometry , Vestibule, Labyrinth , X-Ray Microtomography , Young Adult
13.
ACS Chem Biol ; 15(11): 2885-2895, 2020 11 20.
Article in English | MEDLINE | ID: mdl-33164499

ABSTRACT

The alarming growth of antibiotic resistance that is currently ongoing is a serious threat to human health. One of the most promising novel antibiotic targets is MraY (phospho-MurNAc-pentapeptide-transferase), an essential enzyme in bacterial cell wall synthesis. Through recent advances in biochemical research, there is now structural information available for MraY, and for its human homologue GPT (GlcNAc-1-P-transferase), that opens up exciting possibilities for structure-based drug design. The antibiotic compound tunicamycin is a natural product inhibitor of MraY that is also toxic to eukaryotes through its binding to GPT. In this work, we have used tunicamycin and modified versions of tunicamycin as tool compounds to explore the active site of MraY and to gain further insight into what determines inhibitor potency. We have investigated tunicamycin variants where the following motifs have been modified: the length and branching of the tunicamycin fatty acyl chain, the saturation of the fatty acyl chain, the 6″-hydroxyl group of the GlcNAc ring, and the ring structure of the uracil motif. The compounds are analyzed in terms of how potently they bind to MraY, inhibit the activity of the enzyme, and affect the protein thermal stability. Finally, we rationalize these results in the context of the protein structures of MraY and GPT.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/chemistry , Catalytic Domain/drug effects , Transferases/antagonists & inhibitors , Transferases/chemistry , Tunicamycin/pharmacology , Bacterial Infections/drug therapy , Bacterial Proteins/metabolism , Clostridium/enzymology , Clostridium Infections/drug therapy , Guanosine Triphosphate/metabolism , Humans , Molecular Docking Simulation , Transferases/metabolism , Transferases (Other Substituted Phosphate Groups)
14.
J Biol Chem ; 295(15): 5136-5151, 2020 04 10.
Article in English | MEDLINE | ID: mdl-32132173

ABSTRACT

Increased plasma concentrations of lipoprotein(a) (Lp(a)) are associated with an increased risk for cardiovascular disease. Lp(a) is composed of apolipoprotein(a) (apo(a)) covalently bound to apolipoprotein B of low-density lipoprotein (LDL). Many of apo(a)'s potential pathological properties, such as inhibition of plasmin generation, have been attributed to its main structural domains, the kringles, and have been proposed to be mediated by their lysine-binding sites. However, available small-molecule inhibitors, such as lysine analogs, bind unselectively to kringle domains and are therefore unsuitable for functional characterization of specific kringle domains. Here, we discovered small molecules that specifically bind to the apo(a) kringle domains KIV-7, KIV-10, and KV. Chemical synthesis yielded compound AZ-05, which bound to KIV-10 with a Kd of 0.8 µm and exhibited more than 100-fold selectivity for KIV-10, compared with the other kringle domains tested, including plasminogen kringle 1. To better understand and further improve ligand selectivity, we determined the crystal structures of KIV-7, KIV-10, and KV in complex with small-molecule ligands at 1.6-2.1 Å resolutions. Furthermore, we used these small molecules as chemical probes to characterize the roles of the different apo(a) kringle domains in in vitro assays. These assays revealed the assembly of Lp(a) from apo(a) and LDL, as well as potential pathophysiological mechanisms of Lp(a), including (i) binding to fibrin, (ii) stimulation of smooth-muscle cell proliferation, and (iii) stimulation of LDL uptake into differentiated monocytes. Our results indicate that a small-molecule inhibitor targeting the lysine-binding site of KIV-10 can combat the pathophysiological effects of Lp(a).


Subject(s)
Apolipoproteins A/antagonists & inhibitors , Apolipoproteins A/metabolism , Fibrin/metabolism , Kringles/drug effects , Small Molecule Libraries/pharmacology , Amino Acid Sequence , High-Throughput Screening Assays , Humans , Ligands , Models, Molecular , Protein Binding , Protein Domains , Sequence Homology
15.
Clin Otolaryngol ; 45(3): 357-363, 2020 05.
Article in English | MEDLINE | ID: mdl-31971348

ABSTRACT

OBJECTIVES: To present hearing results after successful primary myringoplasty surgeries registered in the Swedish Quality Registry for Myringoplasty and to evaluate the chance of hearing improvement and the risk of hearing loss. DESIGN: A retrospective nationwide cohort study based on prospectively collected registry data between 2002 and 2012. SETTINGS: Registry data from secondary and tertiary hospitals performing myringoplasty. PARTICIPANTS: Patients with healed tympanic membrane after primary myringoplasty surgery performed from 2002 to 2012 in Sweden. MAIN OUTCOME MEASURES: Postoperative hearing results, hearing gain and air-bone gap (ABG). RESULTS: In 2226 myringoplasties, air conduction audiograms were recorded, and the average preoperative pure tone average (PTA4 ) of the group was 28.5 dB, which improved postoperatively to 19.6 dB with an average of 8.8 dB improvement. Bone conduction was measured for 1476 procedures. Closure of the ABG to 10 dB or less was achieved in 51% of the ears and to less than 20 dB in 89% of the ears. Sixty-one percent of patients with preoperatively deteriorated hearing experienced improved hearing, but 3% of all patients experienced deteriorated hearing. After the surgery, 93% of the patients were satisfied. CONCLUSIONS: Hearing results after successful myringoplasty surgery are often favourable, but although the tympanic membrane is healed, hearing improvement is not guaranteed, and hearing deterioration can also occur.


Subject(s)
Hearing/physiology , Myringoplasty , Tympanic Membrane Perforation/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Auditory Threshold/physiology , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Patient Satisfaction , Recovery of Function , Registries , Retrospective Studies , Sweden , Treatment Outcome , Tympanic Membrane Perforation/complications , Tympanic Membrane Perforation/physiopathology , Young Adult
16.
ChemMedChem ; 15(3): 324-337, 2020 02 05.
Article in English | MEDLINE | ID: mdl-31808981

ABSTRACT

Crystallography provides structural information crucial for fragment optimization, however several criteria must be met to screen directly on protein crystals as soakable, well-diffracting specimen must be available. We screened a 96-fragment library against the tRNA-modifying enzyme TGT using crystallography. Eight hits, some with surprising binding poses, were detected. However, the amount of data collection, reduction and refinement is assumed substantial. Therefore, having a reliable cascade of fast and cost-efficient methods available for pre-screening before embarking to elaborate crystallographic screening appears beneficial. This allows filtering of compounds to the most promising hits, available to rapidly progress from hit-to-lead. But how to ensure that this workflow is reliable? To answer this question, we also applied SPR and NMR to the same screening sample to study whether identical hits are retrieved. Upon hit-list comparisons, crystallography shows with NMR and SPR, only one overlapping hit and all three methods shared no common hits. This questions a cascade-type screening protocol at least in the current example. Compared to crystallography, SPR and NMR detected higher percentages of non-active-site binders suggesting the importance of running reporter ligand-based competitive screens in SPR and NMR, a requirement not needed in crystallography. Although not specific, NMR proved a more sensitive method relative to SPR and crystallography, as it picked up the highest numbers of binders.


Subject(s)
Enzyme Inhibitors/pharmacology , Pentosyltransferases/antagonists & inhibitors , Small Molecule Libraries/pharmacology , Crystallography, X-Ray , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Enzyme Inhibitors/chemistry , Models, Molecular , Molecular Structure , Pentosyltransferases/isolation & purification , Pentosyltransferases/metabolism , Small Molecule Libraries/chemistry , Structure-Activity Relationship , Zymomonas/enzymology
17.
Laryngoscope ; 129(1): 209-215, 2019 01.
Article in English | MEDLINE | ID: mdl-30284250

ABSTRACT

OBJECTIVES/HYPOTHESIS: Postoperative tinnitus and taste disturbances after myringoplasty are more common than previously reported. STUDY DESIGN: This study was a retrospective analysis of prospectively collected data from the Swedish National Quality Registry for Myringoplasty. METHODS: The analysis was performed on extracted data from all counties in Sweden collected from database A from 2002 to 2012 and database B from 2013 to 2016. Tinnitus and taste disturbance complications 1 year after myringoplasty were analyzed in relation to gender, age, procedure, and success rate. In database A, physicians reported tinnitus and taste disturbances. In database B, patients reported the complications. RESULTS: A major difference was found when the complications were reported by physicians compared to when the complications were reported by patients. In database A, tinnitus was reported in 1.2% of the patients and taste disturbances in 0.5%. In database B, the frequencies were 12.3% and 11.2%, respectively. Tinnitus and taste disturbances were more frequent after conventional myringoplasty compared to those after fat grafting and were more frequent after primary compared to those after revision surgery when reported by physicians. Patients, however, reported the same frequency of tinnitus after fat graft myringoplasty compared to that after conventional myringoplasty (12.0% vs. 12.6%) and fewer taste disturbances after revision surgery. In follow-up assessments, complications persisted after surgery over a long time period. CONCLUSION: Tinnitus and taste disturbances are more common after myringoplasty when patients report their symptoms than when physicians report the symptoms. LEVEL OF EVIDENCE: 2b Laryngoscope, 129:209-215, 2019.


Subject(s)
Myringoplasty/adverse effects , Postoperative Complications , Taste Disorders/etiology , Tinnitus/etiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Databases, Factual , Female , Humans , Male , Middle Aged , Myringoplasty/methods , Outcome Assessment, Health Care/methods , Patient Reported Outcome Measures , Physicians , Registries , Reoperation/adverse effects , Retrospective Studies , Sex Factors , Sweden , Young Adult
18.
Arch Oral Biol ; 97: 109-115, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30384151

ABSTRACT

OBJECTIVES: This study tested the hypothesis that modulation of jaw sensorimotor control by intraoral dental appliance can reduce postural sway during quiet standing and hence improve standing balance, in patients with whiplash associated disorders (WAD) and non-trauma neck pain. DESIGN: Postural sway during quiet standing with feet together was examined in 54 WAD patients (40 females) and 10 non-trauma patients (8 females) using wireless 3D movement recording technique. Recordings were performed alternating without and with intraoral dental appliance, and with closed eyes and open eyes, respectively. In this protocol the participants served as their own controls. A reference group of 30 healthy subjects (17 females) was also recorded. Each recording lasted 120 s, followed by 3-5 min of rest. Speed, acceleration and perimeter of postural sway area were documented. RESULTS: In the patients, but not in the healthy group, the intraoral dental appliance instantly and significantly reduced standing postural sway in recordings with closed and open eyes. CONCLUSIONS: The prompt reduction in standing postural sway from intervention by intraoral dental appliance i.e. improved standing balance, suggests a potent effect on the postural control system by modulation of the jaw sensorimotor system, probably involving reflex transmission. The result opens for new insight into mechanisms behind postural control and the pathophysiology of balance disorders, and adds to the knowledge on plasticity of the nervous system. It may help developing new procedures for assessment and management of impaired balance in WAD and non-trauma neck pain patients.


Subject(s)
Neck Pain/physiopathology , Occlusal Splints , Postural Balance/physiology , Standing Position , Whiplash Injuries/physiopathology , Adult , Female , Humans , Male
19.
PLoS One ; 13(6): e0198442, 2018.
Article in English | MEDLINE | ID: mdl-29856847

ABSTRACT

BACKGROUND: Due to the surrounding bone, the human inner ear is relatively inaccessible and difficult to reach for cellular and molecular analyses. However, these types of investigations are needed to better understand the etiology, pathophysiology and progression of several inner ear disorders. Moreover, the fluid from the inner ear cannot be sampled for micro-chemical analyses from healthy individuals in vivo. Therefore, in the present paper, we studied patients with vestibular schwannoma (VS) undergoing trans-labyrinthine surgery (TLS). Our primary aim was to identify perilymph proteins in patients with VS on an individual level. Our second aim was to investigate the proteins identified at a functional level and our final aim was to search for biological markers for tumor-associated hearing loss and tumor diameter. METHODS AND FINDINGS: Sixteen patients underwent TLS for sporadic VS. Perilymph was aspirated through the round window before opening the labyrinth. One sample was contaminated and excluded resulting in 15 usable samples. Perilymph samples were analyzed with an online tandem LTQ-Orbitrap mass spectrometer. Data were analyzed with MaxQuant software to identify the total number of proteins and to quantify proteins in individual samples. Protein function was analyzed using the PANTHER Overrepresentation tool. Associations between perilymph protein content, clinical parameters, tumor-associated hearing loss and tumor diameter were assessed using Random Forest and Boruta. In total, 314 proteins were identified; 60 in all 15 patients and 130 proteins only once in 15 patients. Ninety-one proteins were detected in at least 12 out of 15 patients. Random Forest followed by Boruta analysis confirmed that alpha-2-HS-glycoprotein (P02765) was an independent variable for tumor-associated hearing loss. In addition, functional analysis showed that numerous processes were significantly increased in the perilymph. The top three enriched biological processes were: 1) secondary metabolic processes; 2) complement activation and 3) cell recognition. CONCLUSIONS: The proteome of perilymph in patients with vestibular schwannoma has an inter-individual stable section. However, even in a cohort with homogenous disease, the variation between individuals represented the majority of the detected proteins. Alpha-2-HS-glycoprotein, P02765, was shown to be an independent variable for tumor-associated hearing loss, a finding that needs to be verified in other studies. In pathway analysis perilymph had highly enriched functions, particularly in terms of increased immune and metabolic processes.


Subject(s)
Biomarkers/metabolism , Hearing Loss/diagnosis , Neurilemmoma/pathology , Perilymph/metabolism , Proteome/metabolism , Chromatography, High Pressure Liquid , Female , Hearing Loss/complications , Hearing Loss/metabolism , Humans , Linear Models , Male , Neurilemmoma/complications , Neurilemmoma/metabolism , Proteome/analysis , Tandem Mass Spectrometry , alpha-2-HS-Glycoprotein/analysis
20.
Cochlear Implants Int ; 19(6): 324-329, 2018 11.
Article in English | MEDLINE | ID: mdl-29877144

ABSTRACT

OBJECTIVES: Dehiscence between the cochlear otic capsule and the facial nerve canal is a rare and relatively newly described pathology. In cochlear implantation (CI), this dehiscence may lead to adverse electric facial nerve stimulation (FNS) already at low levels, rendering its use impossible. Here, we describe an assessment technique to foresee this complication. METHODS: Pre- and postoperative computed tomography (CT) scans and intraoperative electrically evoked auditory brainstem response (e-ABR) measurements were analyzed in two patients with cochlear-facial dehiscence (CFD). RESULTS: Because of the relatively low resolution, the confirmation of CFD with a clinical CT was difficult. The e-ABR displayed a large potential with 6 and 7.5 ms latency, respectively, which did not occur otherwise. DISCUSSION: Potential strategies to resolve and manage FNS are described. CONCLUSION: Prediction of FNS by assessing the distance between the labyrinthine portion of the facial nerve and the cochlea is difficult using conventional CT scans. A large evoked late myogenic potential at low stimulation levels during intraoperative e-ABR measurement may foresee FNS at CI activation.


Subject(s)
Cochlear Implantation/adverse effects , Cochlear Implants/adverse effects , Electric Stimulation/adverse effects , Evoked Potentials, Auditory, Brain Stem/physiology , Hearing Loss, Sensorineural/physiopathology , Aged , Cochlea/diagnostic imaging , Cochlea/physiopathology , Facial Nerve/diagnostic imaging , Facial Nerve/physiopathology , Hearing Loss, Sensorineural/diagnostic imaging , Hearing Loss, Sensorineural/surgery , Humans , Intraoperative Neurophysiological Monitoring/methods , Male , Tomography, X-Ray Computed
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