CHLOROPLAST UNUSUAL POSITIONING 1 is a plant-specific actin polymerization factor regulating chloroplast movement.

Plants have unique responses to fluctuating light conditions. One such response involves chloroplast photorelocation movement, which optimizes photosynthesis under weak light by the accumulation of chloroplasts along the periclinal side of the cell, which prevents photodamage under strong light by avoiding chloroplast positioning toward the anticlinal side of the cell. This light-responsive chloroplast movement relies on the reorganization of chloroplast actin (cp-actin) filaments. Previous studies have suggested that CHLOROPLAST UNUSUAL POSITIONING 1 (CHUP1) is essential for chloroplast photorelocation movement as a regulator of cp-actin filaments. In this study, we conducted comprehensive analyses to understand CHUP1 function. Functional, fluorescently tagged CHUP1 colocalized with and was coordinately reorganized with cp-actin filaments on the chloroplast outer envelope during chloroplast movement in Arabidopsis thaliana. CHUP1 distribution was reversibly regulated in a blue light- and phototropin-dependent manner. X-ray crystallography revealed that the CHUP1-C-terminal domain shares structural homology with the formin homology 2 (FH2) domain, despite lacking sequence similarity. Furthermore, the CHUP1-C-terminal domain promoted actin polymerization in the presence of profilin in vitro. Taken together, our findings indicate that CHUP1 is a plant-specific actin polymerization factor that has convergently evolved to assemble cp-actin filaments and enables chloroplast photorelocation movement.

Mutation of the imprinted gene OsEMF2a induces autonomous endosperm development and delayed cellularization in rice.

In angiosperms, endosperm development comprises a series of developmental transitions controlled by genetic and epigenetic mechanisms that are initiated after double fertilization. Polycomb repressive complex 2 (PRC2) is a key component of these mechanisms that mediate histone H3 lysine 27 trimethylation (H3K27me3); the action of PRC2 is well described in Arabidopsis thaliana but remains uncertain in cereals. In this study, we demonstrate that mutation of the rice (Oryza sativa) gene EMBRYONIC FLOWER2a (OsEMF2a), encoding a zinc-finger containing component of PRC2, causes an autonomous endosperm phenotype involving proliferation of the central cell nuclei with separate cytoplasmic domains, even in the absence of fertilization. Detailed cytological and transcriptomic analyses revealed that the autonomous endosperm can produce storage compounds, starch granules, and protein bodies specific to the endosperm. These events have not been reported in Arabidopsis. After fertilization, we observed an abnormally delayed developmental transition in the endosperm. Transcriptome and H3K27me3 ChIP-seq analyses using endosperm from the emf2a mutant identified downstream targets of PRC2. These included >100 transcription factor genes such as type-I MADS-box genes, which are likely required for endosperm development. Our results demonstrate that OsEMF2a-containing PRC2 controls endosperm developmental programs before and after fertilization.

Presence of herpesviruses, parvoviruses, and polyomaviruses in sinonasal lymphoma.

PURPOSE: Sinonasal lymphoma (SL) is a rare lymphatic neoplasm of the nasal cavities, paranasal sinuses and nasopharynx. Whereas some risk factors for SL subtypes have been identified, their aetiology is unknown. Along with other predisposing factors, the viral association of lymphomas, such as Epstein-Barr virus (EBV) and Burkitt and Hodgkin lymphomas, is well-established. Modern molecular biology techniques have enabled the discovery of novel human viruses, exemplified by the protoparvovirus cutavirus (CuV), associated with cutaneous T-cell lymphoma. These findings, and the anatomical location of the sinonasal tract with its rich microbiome and infectious agents, justify in-depth studies among SL. METHODS: We analysed the presence of 20 viruses of Orthoherpesviridae, Parvoviridae, and Polyomaviridae by qPCR in 24 SL tumours. We performed RNAscope in situ hybridisation (RISH) to localize the viruses. Parvovirus-specific IgG was analysed by enzyme immunoassay and targeted next-generation sequencing (NGS) was applied to detect CuV in plasma. RESULTS: We detected viral DNA in 15/24 (63%) tumours; nine of EBV, six of human herpesvirus (HHV) -7, four each of HHV-6B and parvovirus B19, two of cytomegalovirus, and one each of CuV and Merkel-cell polyomavirus. We found tumours with up to four viruses per tumour, and localized CuV and EBV DNAs by RISH. Two of the ten plasma samples exhibited CuV IgG, and one plasma sample demonstrated CuV viremia by NGS. CONCLUSION: Viruses were frequent findings in SL. The EBV detection rate was high in diffuse large B-cell lymphoma, and co-detections with other viruses were prevalent.

Integration of 3D-printed middle ear models and middle ear prostheses in otosurgical training.

BACKGROUND: In otosurgical training, cadaveric temporal bones are primarily used to provide a realistic tactile experience. However, using cadaveric temporal bones is challenging due to their limited availability, high cost, and potential for infection. Utilizing current three-dimensional (3D) technologies could overcome the limitations associated with cadaveric bones. This study focused on how a 3D-printed middle ear model can be used in otosurgical training. METHODS: A cadaveric temporal bone was imaged using microcomputed tomography (micro-CT) to generate a 3D model of the middle ear. The final model was printed from transparent photopolymers using a laser-based 3D printer (vat photopolymerization), yielding a 3D-printed phantom of the external ear canal and middle ear. The feasibility of this phantom for otosurgical training was evaluated through an ossiculoplasty simulation involving ten otosurgeons and ten otolaryngology-head and neck surgery (ORL-HNS) residents. The participants were tasked with drilling, scooping, and placing a 3D-printed partial ossicular replacement prosthesis (PORP). Following the simulation, a questionnaire was used to collect the participants' opinions and feedback. RESULTS: A transparent photopolymer was deemed suitable for both the middle ear phantom and PORP. The printing procedure was precise, and the anatomical landmarks were recognizable. Based on the evaluations, the phantom had realistic maneuverability, although the haptic feedback during drilling and scooping received some criticism from ORL-HNS residents. Both otosurgeons and ORL-HNS residents were optimistic about the application of these 3D-printed models as training tools. CONCLUSIONS: The 3D-printed middle ear phantom and PORP used in this study can be used for low-threshold training in the future. The integration of 3D-printed models in conventional otosurgical training holds significant promise.

Herpesviruses, polyomaviruses, parvoviruses, papillomaviruses, and anelloviruses in vestibular schwannoma.

Etiology of vestibular schwannoma (VS) is unknown. Viruses can infect and reside in neural tissues for decades, and new viruses with unknown tumorigenic potential have been discovered. The presence of herpesvirus, polyomavirus, parvovirus, and anellovirus DNA was analyzed by quantitative PCR in 46 formalin-fixed paraffin-embedded VS samples. Five samples were analyzed by targeted next-generation sequencing. Viral DNA was detected altogether in 24/46 (52%) tumor samples, mostly representing anelloviruses (46%). Our findings show frequent persistence of anelloviruses, considered normal virome, in VS. None of the other viruses showed an extensive presence, thereby suggesting insignificant role in VS.

Assessment of subjective image quality, contrast to noise ratio and modulation transfer function in the middle ear using a novel full body cone beam computed tomography device.

BACKGROUND: Multi slice computed tomography (MSCT) is the most common used method in middle ear imaging. However, MSCT lacks the ability to distinguish the ossicular chain microstructures in detail resulting in poorer diagnostic outcomes. Novel cone beam computed tomography (CBCT) devices' image resolution is, on the other hand, better than MSCT resolution. The aim of this study was to optimize imaging parameters of a novel full body CBCT device to obtain optimal contrast to noise ratio (CNR) with low effective dose, and to optimize its clinical usability. METHODS: Imaging of five anonymous excised human cadaver temporal bones, the acquisition of the effective doses and the CNR measurements were performed for images acquired on using Planmed XFI® full body CBCT device (Planmed Oy, Helsinki, Finland) with a voxel size of 75 µm. All images acquired from the specimens using 10 different imaging protocols varying from their tube current exposure time product (mAs) and tube voltage (kVp) were analyzed for eight anatomical landmarks and evaluated by three evaluators. RESULTS: With the exception of protocol with 90 kVp 100 mAs, all other protocols used are competent to image the finest structures. With a moderate effective dose (86.5 µSv), protocol with 90 kV 450 mAs was chosen the best protocol used in this study. A significant correlation between CNR and clinical image quality of the protocols was observed in linear regression model. Using the optimized imaging parameters, we were able to distinguish even the most delicate middle ear structures in 2D images and produce accurate 3D reconstructions. CONCLUSIONS: In this ex vivo experiment, the new Planmed XFI® full body CBCT device produced excellent 2D resolution and easily created 3D reconstructions in middle ear imaging with moderate effective doses. This device would be suitable for middle ear diagnostics and for e.g., preoperative planning. Furthermore, the results of this study can be used to optimize the effective dose by selecting appropriate exposure parameters depending on the diagnostic task.

Tubomanometry correlations with patient characteristics and other diagnostic tests of Eustachian tube dysfunction: a cohort study of 432 ears.

OBJECTIVES: Currently, there is no consensus regarding the best protocol for diagnosing Eustachian tube dysfunction (ETD). We aimed to evaluate how patient characteristics affect tubomanometry (TMM) results. If an association between patient characteristics and TMM results exists, this should be considered in TMM interpretation. We also wanted to study if TMM correlates with other diagnostic tools of ETD. METHODS: A retrospective chart review was conducted on all patients with TMM results available from November 2011 to October 2020 at a tertiary referral center, including 432 ears from 219 patients. An association between diagnostic tests and patient characteristics was assessed using regression models. Spearman's rank correlation was used to analyze correlations between diagnostic tests. RESULTS: None of the studied patient characteristics (age, gender, body mass index, smoking, sinonasal disease) was associated with TMM results except for pollen allergy (OR 1.74, 95% CI 1.15-2.63, P = 0.009). TMM results correlated with Valsalva maneuver performance (P < 0.001, ρ = 0.31) and otomicroscopic signs of inadequate middle ear ventilation (P < 0.001, ρ = 0.28). The Eustachian tube dysfunction questionnaire-7 (ETDQ-7) score did not correlate with any diagnostic method. CONCLUSIONS: TMM results are unaffected by patient characteristics other than pollen allergy. Thus, TMM may be used in ETD diagnostics in a wide variety of patients with straightforward interpretation. TMM correlates with other diagnostic tests studied but not with ETDQ-7. ETDQ-7 does not seem to correlate with other diagnostic tests and appears nonspecific in ETD diagnostics.

The presence of herpesviruses in malignant but not in benign or recurrent pleomorphic adenomas.

BACKGROUND: The etiology of salivary gland tumors is mainly unknown. The anatomical location of the salivary glands, with the mucosal pathway to the oral cavity and its rich microbiome, raises the question of potential viral background. OBJECTIVE: This study focuses on the potential presence of herpes-, polyoma- and parvoviruses in pleomorphic adenoma (PA), recurrent pleomorphic adenoma (RPA) and carcinoma ex pleomorphic adenoma (CaxPA). METHODS: Thirty different viruses were analyzed by PCR-based assays in 68 formalin-fixed paraffin-embedded salivary gland tumors (25 PA, 31 RPA and 12 CaxPA). RESULTS: Virus DNA was detected altogether in 19/68 (28%) tumor samples. Human herpesviruses 6B and 7 (HHV-6B and HHV-7) and Epstein-Barr virus (EBV) were frequently and almost exclusively found in CaxPA (5/12, 7/12, and 3/12, respectively). Within the 7 CaxPA that were virus-positive, 3 samples contained 3, and 1 sample even 4, different viruses. Infrequent viral positivity was shown for parvovirus B19 and cutavirus, as well as Merkel cell and Malawi polyomaviruses. CONCLUSIONS: Our unexpected finding of herpesvirus DNA almost exclusively in CaxPA tissues deserves further in-depth studies.

Inner ear decompression sickness in Finland: a retrospective 20-year multicenter study.

Introduction: Inner ear decompression sickness (IEDCS) is a condition from which only a minority of patients recover completely, the majority ending up with mild to moderate residual symptoms. IEDCS has been reported after deep technical dives using mixed breathing gases, and moderate recreational dives with compressed air as the breathing gas. Considering this and the high proportion of technical diving in Finland, a comparison between IEDCS cases resulting from technical and recreational dives is warranted. Methods: This is a retrospective examination of IEDCS patients treated at Hyperbaric Center Medioxygen or National Hyperbaric Centre of Turku University Hospital from 1999 to 2018. Patients were included if presenting with hearing loss, tinnitus, or vertigo and excluded if presenting only with symptoms of middle ear or cerebellar involvement. Patients were divided into technical and recreational divers, based on incident dive. Results: A total of 89 (15.6%) of all DCS patients presented with IEDCS, two-thirds treated during the latter decade. The most common predisposing factors were consecutive days of diving (47.2%), multiple dives per day (53.9%), and factors related to an increase in intrathoracic pressure (27.0%). The symptoms were cochlear in 19.1% and vestibular in 93.3% of cases, symptoms being more common and severe in technical divers. Complete recovery was achieved in 64.5% of technical and 71.4% of recreational divers. Conclusion: The incidence of IEDCS in Finland is increasing, most likely due to changing diving practices. A comprehensive examination should be carried out after an incident of IEDCS in all cases, irrespective of clinical recovery.

Management of jugular bulb injury during drilling of the internal auditory canal (ICA) for vestibular schwannoma surgery.

The retrosigmoid approach for vestibular schwannoma surgery has remained the standard approach by most neurosurgeons. Drilling the posterior wall of the internal auditory meatus (IAM) is an essential step in removing the intrameatal tumor. During IAM drilling, three anatomical structures can be encountered, including the posterior semicircular canal, vestibular aqueduct, and jugular bulb. Any of these can be injured during drilling, especially if the jugular bulb lies above the inferior edge of the IAM. Although IAM drilling is performed in most vestibular schwannoma surgeries, information on how to manage complications such as jugular bulb injury is lacking. Here we use an intraoperative video to demonstrate how to manage the inadvertent injury to the jugular bulb in order to avoid massive blood loss. We present a case of a 39-year-old woman with hearing loss, diagnosed with a cerebellopontine angle mass extending into the IAM. Surgery was required due to tumor progression. We used the retrosigmoid approach to access the tumor. During IAM drilling, the jugular bulb was injured. A thin layer of bone wax was applied under continuous suction. The margins of the wax were then gently compressed with a dissector; great care was taken to avoid pushing the wax into the jugular bulb. Excess bone wax was removed (video 1). A small diamond drill (2 mm) was used for further drilling. Our instructional video shows the surgical approach, microsurgical anatomy, and technical aspects of managing massive bleeding from jugular bulb injury. It should therefore be helpful for young neurosurgeons.

Measurement of enzymatic and motile activities of Arabidopsis myosins by using Arabidopsis actins.

There are two classes of myosin, XI and VIII, in higher plants. Myosin XI moves actin filaments at high speed and its enzyme activity is also very high. In contrast, myosin VIII moves actin filaments very slowly with very low enzyme activity. Because most of these enzymatic and motile activities were measured using animal skeletal muscle α-actin, but not plant actin, they would not accurately reflect the actual activities in plant cells. We thus measured enzymatic and motile activities of the motor domains of two Arabidopsis myosin XI isoforms (MYA2, XI-B), and one Arabidopsis myosin VIII isoform (ATM1), by using three Arabidopsis actin isoforms (ACT1, ACT2, and ACT7). The measured activities were different from those measured by using muscle actin. Moreover, Arabidopsis myosins showed different enzymatic and motile activities when using different Arabidopsis actin isoforms. Our results suggest that plant actin should be used for measuring enzymatic and motile activities of plant myosins and that different actin isoforms in plant cells might function as different tracks along which affinities and velocities of each myosin isoform are modulated.

Jugulotympanic paragangliomas in southern Finland: a 40-year experience suggests individualized surgical management.

Treatment of jugulotympanic paragangliomas (JTPGLs) remains challenging with no clear guidelines for management or follow-up. The aim of this retrospective case-note study was to assess long-term results of operatively and conservatively managed JTPGLs between years 1974-2013. A total of 36 patients with JTPGLs were identified. Clinical characteristics and management outcomes of patients were reviewed. Data were extracted on demographics, symptoms, timing of diagnosis, tumor location and size, embolization, and management, including pre- and post-operative imaging, analysis of operative techniques, and follow-up. Pulsatile tinnitus and hearing loss were the most common presenting symptoms. Thirty-four (94 %) patients were treated with primary surgical therapy and two (6 %) with radiotherapy. The surgical approaches included endaural approach for Fisch Class A tumors and a variety of approaches for Fisch Class B-D tumors with an increasing predilection for function-preserving surgery. Eight (24 %) patients received subtotal resection. Five (15 %) patients had a local recurrence within 10 years after primary surgery. Two (6 %) patients suffered a permanent cranial nerve (CN) deficit after primary surgery. We advocate radical surgery when tumor resection is possible without compromising CNs. Function-preserving surgery with at least a 10-year follow-up for Fisch Class B-D tumors should be considered if CNs are in danger.

Distinct Biochemical Properties of Arabidopsis thaliana Actin Isoforms.

Plants and animals express multiple actin isoforms in a manner that is dependent on tissues, organs and the stage of development. Previous genetic analyses suggested that individual actin isoforms have specific roles in cells, but there is little biochemical evidence to support this hypothesis. In this study, we purified four recombinant Arabidopsis actin isoforms, two major vegetative actin isoforms, ACT2 and ACT7, and two major reproductive isoforms, ACT1 and ACT11, and characterized them biochemically. Phalloidin bound normally to the filaments of the two reproductive actins as well as to the filaments of skeletal muscle actin. However, phalloidin bound only weakly to ACT7 filaments and hardly at all to ACT2 filaments, despite the conserved sequence of the phalloidin-binding site. Polymerization and phosphate release rates among these four actin isoforms were also significantly different. Moreover, interactions with profilin (PRF) were also different among the four Arabidopsis actin isoforms. PRF1 and PRF2 inhibited the polymerization of ACT1, ACT11 and ACT7, while ACT2 was only weakly affected. Plant actin isoforms have different biochemical properties. This result supports the idea that actin isoforms play specific roles to achieve multiple cell functions.

Transient, afferent input-dependent, postnatal niche for neural progenitor cells in the cochlear nucleus.

In the cochlear nucleus (CN), the first central relay of the auditory pathway, the survival of neurons during the first weeks after birth depends on afferent innervation from the cochlea. Although input-dependent neuron survival has been extensively studied in the CN, neurogenesis has not been evaluated as a possible mechanism of postnatal plasticity. Here we show that new neurons are born in the CN during the critical period of postnatal plasticity. Coincidently, we found a population of neural progenitor cells that are controlled by a complex interplay of Wnt, Notch, and TGFß/BMP signaling, in which low levels of TGFß/BMP signaling are permissive for progenitor proliferation that is promoted by Wnt and Notch activation. We further show that cells with activated Wnt signaling reside in the CN and that these cells have high propensity for neurosphere formation. Cochlear ablation resulted in diminishment of progenitors and Wnt/ß-catenin-active cells, suggesting that the neonatal CN maintains an afferent innervation-dependent population of progenitor cells that display active canonical Wnt signaling.

Depressed Spousal Caregivers Have Psychological Stress Unrelated to the Progression of Alzheimer Disease: A 3-Year Follow-Up Report, Kuopio ALSOVA Study.

OBJECTIVE: To explore family caregiver (FC) long-term psychological distress after Alzheimer disease (AD) diagnosis in a family member. METHODS: FC (n = 236) and patients with AD were prospectively followed up to 36 months after AD diagnosis. FC psychological distress was evaluated using the General Health Questionnaire (GHQ). Furthermore, caregiver depressive symptoms and sense of coherence, along with AD patient measurements, were measured at baseline and annually. Generalized estimating equation models were applied to study associations of these baseline factors to caregiver GHQ. RESULTS: After 36 months of follow-up, spousal caregivers (SCs) GHQ was significantly higher (P < .001) than in the nonspousal caregivers (NSCs). The difference in GHQ scores was associated by depressive symptoms (P < .001) at baseline, and the depressed SCs have more severe distress than NSCs over the observation period. CONCLUSION: During longitudinal caregiving, spousal and depressed caregivers of patients with AD report higher and increasing psychological stress than nonspousal and nondepressed caregivers. Spousal relationship, caregivers' depressive symptoms, and the severity of patients' neuropsychological symptoms at the time of AD diagnosis predict the trajectory of psychological distress. The current study highlights the need for evaluating AD caregiver mental health and level of coping.

Experience of head and neck extracranial schwannomas in a whole population-based single-center patient series.

Due to their rarity most of the literature concerning head and neck extracranial schwannomas consists of case reports and small patient series. The aim of the study was to describe population-based incidence, presenting signs and symptoms, management and outcome of head and neck extracranial schwannomas in a larger patient group. All the head and neck extracranial schwannoma patients managed during 1987-2008 at the Helsinki University Central Hospital with a referral area of 1.5 million inhabitants were searched. Altogether 47 patients were identified and subjected to retrospective chart review. Population-based incidence of head and neck extracranial schwannomas was 0.14/100,000/year. Eighty-eight percent of the patients had symptoms, which had lasted on average for 11.5 months prior to diagnosis. Presenting signs and symptoms were diverse depending on the affected nerve. Ninety-four percent of the patients were treated surgically. Sixty-four percent of the operations were macroscopically radical. The tumor capsule was intentionally left in place in 9 %. Surgery-related complications were detected in only 7 % of the patients, but 1 month postoperatively 52 % of them had symptoms, majority relating to different nerve deficits. Treatment of extracranial head and neck schwannomas remains challenging. The tumor is benign, and it grows slowly in a vast majority of cases, but its symptoms are highly variable. Correct timing of surgery is essential, as also patients who are preoperatively asymptomatic may suffer severe postoperative morbidity. Preoperative patient counseling needs to address the risks of neurological sequelae.

[Tympanic membrane perforation ]. / Tärykalvoreikä.

Tympanic membrane perforation may be caused by, e.g., trauma or acute or chronic middle ear infection. Perforation causes conductive hearing loss. Since it predisposes to infections, it is important to keep the ear dry. In most cases traumatic perforations heal spontaneously. Perforations caused by acute middle ear infections are treated with antibiotics. Chronic perforation due to chronic middle ear infection or cholesteatoma will usually not heal without surgery. Most perforation cases can be taken care of in primary care. ENT consultation is needed when alarming signs, such as continuous pain, vertigo or facial paralysis exist, or if the perforation persists.

[Acute mastoiditis in children]. / Lasten akuutti mastoidiitti.

Acute mastoiditis in children develops when acute otitis media (AOM) spreads into the mastoid air cells inside the temporal bone. The diagnosis is based on clinical findings of AOM with simultaneous signs of infection in the mastoid area. The most common pathogen causing acute mastoiditis in children is Streptococcus pneumoniae. Intravenous antimicrobial medication, tympanostomy and microbial sample are the cornerstones of the treatment. If a complication of mastoiditis is suspected, imaging studies are needed, preferably with magnetic resonance imaging. The most common complication of acute mastoiditis is a subperiosteal abscess.

Balloon Eustachian Tuboplasty-A Feasible Double-Blinded Sham Surgery Randomized Clinical Trial Protocol to Study Efficacy.

INTRODUCTION: Balloon Eustachian tuboplasty (BET) is used to treat obstructive Eustachian tube dysfunction (OETD) and recurrent otitis media with effusion (OME). However, there are no indisputable evidence of its efficacy. Here, we present a multicenter, double-blinded, randomized, placebo-controlled trial (MDRCT) design to evaluate the efficacy of BET, and the results of a pilot trial with 3- and 12-months' follow-up. MATERIAL AND METHODS: This was a prospective MDRCT. For a pilot study, OETD (n = 10) and OME (n = 5) patients were recruited and followed. Detailed inclusion and exclusion criteria were used. Participants were randomized at beginning of the operation to active or sham surgery. All procedures were performed under local anesthesia. Controls were performed in double-blinded manner (both patient and physician), at 3 and 12 months after the procedure. RESULTS: Altogether, 20 ears were treated and followed for 12 months, including 14 active BETs and 6 sham surgeries. Both the active and sham surgery were performed under local anesthesia without problems or deviations from the protocol. There were no differences in the preoperative symptoms (ETDQ-7) or objective measures (tympanometry, Valsalva and Toynbee maneuvers, tubomanometry, Eustachian tube score) between active and sham surgery arms. During follow-up, we noticed largely similar reduction in subjective symptoms and improvement in Eustachian tube score both in active and sham surgery arms. CONCLUSIONS: The pilot study demonstrates that our MDRCT protocol is feasible, and that blinded RCTs are dearly needed to objectively measure the efficacy of BET. LEVEL OF EVIDENCE: 2 Laryngoscope, 134:1874-1881, 2024.