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Objective: This study reported a family with most members affected by Czech dysplasia. We examined the patients' clinical, laboratory, and imaging characteristics and evaluated their functional capacity using the Stanford Health Assessment Questionnaire-Disability Index., Methods: The method used was case series description and literature review., Results: This study showed that the pathogenic variant c.823C>T in the COL2A1 gene, which is a characteristic of Czech dysplasia, was found in 12 Brazilian individuals. Half of the patients in this family met the criteria for rheumatoid arthritis (RA) based on the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria. Patients had arthritis in their hand joints, synovitis detected by ultrasound, and alterations in inflammatory tests. The Stanford Health Assessment Questionnaire-Disability Index assessment revealed that all patients exhibited moderate-to-severe functional disability. What distinguish Czech dysplasia from RA are an autosomal dominant inheritance pattern, platyspondyly, sensorineural hearing loss, and shortening of the metatarsal bones., Conclusions: It is important to consider Czech dysplasia as a potential differential diagnosis for RA. This autosomal dominant skeletal dysplasia is associated with normal height, short metatarsals, platyspondyly, hearing loss, enlarged epiphyses, and precocious osteoarthritis. Inflammatory findings such as arthritis, synovitis, and alteration of inflammatory markers may also be present in individuals with Czech dysplasia., (© Japan College of Rheumatology 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Obesity is characterized by low-grade inflammation, energy imbalance and impaired thermogenesis. The role of regulatory T cells (Treg) in inflammation-mediated maladaptive thermogenesis is not well established. Here, we find that the p38 pathway is a key regulator of T cell-mediated adipose tissue (AT) inflammation and browning. Mice with T cells specifically lacking the p38 activators MKK3/6 are protected against diet-induced obesity, leading to an improved metabolic profile, increased browning, and enhanced thermogenesis. We identify IL-35 as a driver of adipocyte thermogenic program through the ATF2/UCP1/FGF21 pathway. IL-35 limits CD8 + T cell infiltration and inflammation in AT. Interestingly, we find that IL-35 levels are reduced in visceral fat from obese patients. Mechanistically, we demonstrate that p38 controls the expression of IL-35 in human and mouse Treg cells through mTOR pathway activation. Our findings highlight p38 signaling as a molecular orchestrator of AT T cell accumulation and function., (© 2024. The Author(s).)

Objective: The main objective of the study was to determine if ultrasonographic measurement of mediastinal shift angle (MSA) can predict postnatal survival in fetuses with isolated left congenital diaphragmatic hernia (CDH). This relatively new technique may be used to enhance antenatal prediction of survival in fetuses with CDH., Methods: A retrospective cross-sectional study was conducted at the Philippine Children's Medical Center involving 16 cases with prenatally diagnosed isolated left CDH and 60 controls with normal fetuses. The cases with prenatally diagnosed isolated left CDH were allocated into two groups: Group A (survivors) and group B (non-survivors). For all fetuses (study and control groups), MSA was determined independently by two operators. The diagnostic capacity of MSA was assessed using the receiver operating characteristic curve., Results: The mean MSA for the control group was 17.18°. Among CDH cases, the mean MSA was 33.04° and 37.57° for survivors and non-survivors, respectively. Results showed that MSA significantly predicted the probability of neonatal survival status (OR = 0.46, P = 0.021). The best cutoff score of MSA based on the receiver operating characteristic curve was 33.80° with 87.50% sensitivity and specificity., Conclusion: MSA has the potential to enhance antenatal prediction of survival in fetuses with CDH and may serve as a guide in prenatal counseling and evaluation of the need for in-utero treatment or postnatal procedures., (© 2024 International Federation of Gynecology and Obstetrics.)

The Eastern Tropical and South-Eastern Pacific region is of global biodiversity importance. At COP26, the governments of Costa Rica, Panama, Colombia, and Ecuador committed to the expansion of existing MPAs to create a new Mega MPA, safeguarding the Eastern Tropical Pacific Marine Corridor. It offers a profound step forward in conservation efforts but is not specifically designed to protect against the more diffuse anthropogenic threats, such as plastic pollution. We combine published data with our own unpublished records to assess the abundance and distribution of plastic pollution in the region. Macro- and microplastic concentrations varied markedly and were not significantly different when comparing areas inside and outside existing MPA boundaries. These findings highlight the diffuse and complex nature of plastic pollution and its ubiquitous presence across MPA boundaries. Understanding the sources and drivers of plastic pollution in the region is key to developing effective solutions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Osteonecrosis of the femoral head (ONFH) is a devastating bone disease that is caused by a disruption of blood supply leading to necrotic cell death. Clinically, it was found that obesity has a high prevalence with ONFH. However, it remains unclear how obesity may directly affect tissue regeneration and bone healing in osteonecrosis (ON). The purpose of this study is to investigate the effects of obesity and weight loss (WL) on ON healing. In this study, we induced obesity and WL in an established surgery-induced ON mouse model via feeding a high-fat diet (HFD) and altering the diet respectively. All mice received a surgical induction of ON of distal femoral epiphysis at the age of 12 weeks. HFD was switched to normal diet (ND) after ON surgery to induce WL. Mouse body weight was recorded weekly. Mouse body composition was scanned by DEXA (Dual-energy X-ray absorptiometry) right after sacrifice at the age of 16 weeks. The distal femoral bone samples were fixed and embedded for histology such as H&E, immunohistochemistry, and TRAP staining. In this study, we found that HFD-induced obesity impaired revascularization and bone remodeling showing decreased vessel areas and reduced osteoblast and osteoclast numbers. WL could rescue obesity-induced bone healing defects. Our study is the first to test the direct effects of obesity and WL on ON bone healing. We believe our work may provide new concepts for osteonecrosis treatment in obese patients., (© 2023 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

The purpose of this study was to determine if short-term outcomes differed for pediatric patients with suspected musculoskeletal infection with or without a preoperative MRI. This was a multicenter, retrospective review of patients aged 0-16 years who presented with atraumatic extremity pain, underwent irrigation and debridement (I&D), and received at least one preoperative or postoperative MRI over a 10-year period. Primary outcomes were time to OR, total I&Ds, readmission rate, time from OR to discharge, and total number of MRIs. Secondary outcomes entailed the rate at which concurrent osteomyelitis was identified in patients with septic arthritis and the extent of the resulting surgical debridement. Of the 104 patients, 72.1% had a preoperative MRI. Patients with a preoperative MRI were significantly less likely to have surgery on the day of admission. No difference was found between groups regarding total I&Ds, readmission rate, time from OR to discharge, and total number of MRIs. Of the 57 patients diagnosed with septic arthritis, those with a preoperative MRI were significantly more likely to have concurrent osteomyelitis identified and to undergo bony debridement in addition to arthrotomy of the joint. In conclusion, patient outcomes are not adversely affected by obtaining a preoperative MRI despite the delay in time to OR. Although preoperative MRI can be beneficial in ruling out other pathologies and identifying the extent of concurrent osteomyelitis, the decision to obtain a preoperative MRI and timing of surgery should be left to the discretion of the treating surgeon.

Altered expression of peripheral myelin protein 22 (PMP22) results in demyelinating peripheral neuropathy. PMP22 exhibits a highly restricted tissue distribution with marked expression in the myelinating Schwann cells of peripheral nerves. Auditory and vestibular Schwann cells and the afferent neurons also express PMP22, suggesting a unique role in hearing and balancing. Indeed, neuropathic patients diagnosed with PMP22-linked hereditary neuropathies often present with auditory and balance deficits, an understudied clinical complication. To investigate the mechanism by which abnormal expression of PMP22 may cause auditory and vestibular deficits, we studied gene-targeted PMP22 -null mice. PMP22 -null mice exhibit an unsteady gait, have difficulty maintaining balance, and live for only ∼3-5 weeks relative to unaffected littermates. Histological analysis of the inner ear revealed reduced auditory and vestibular afferent nerve myelination and profound Na + channel redistribution without PMP22. Yet, Na + current density was unaltered, in stark contrast to increased K + current density. Atypical postsynaptic densities and a range of neuronal abnormalities in the organ of Corti were also identified. Analyses of auditory brainstem responses (ABRs) and vestibular sensory-evoked potential (VsEP) revealed that PMP22 -null mice had auditory and vestibular hypofunction. These results demonstrate that PMP22 is required for hearing and balance, and the protein is indispensable for the formation and maintenance of myelin in the peripheral arm of the eighth nerve. Our findings indicate that myelin abnormalities and altered signal propagation in the peripheral arm of the auditory nerve are likely causes of auditory deficits in patients with PMP22-linked neuropathies., (Copyright © 2024 Lee et al.)

Mesomelic skeletal dysplasia is a heterogeneous group of skeletal disorders that has grown since the molecular basis of these conditions is in the process of research and discovery. Here, we report a Brazilian family with eight affected members over three generations with a phenotype similar to mesomelic Kantaputra dysplasia. This family presents marked shortening of the upper limbs with hypotrophy of the lower limbs and clubfeet without synostosis. Array-based CNV analysis and exome sequencing of four family members failed to show any region or gene candidate. Interestingly, males were more severely affected than females in this family, suggesting that gender differences could play a role in the phenotypic expressivity of this condition., (© 2023 Wiley Periodicals LLC.)

The inner ear is the hub where hair cells (HCs) transduce sound, gravity, and head acceleration stimuli to the brain. Hearing and balance rely on mechanosensation, the fastest sensory signals transmitted to the brain. The mechanoelectrical transducer (MET) channel is the entryway for the sound-balance-brain interface, but the channel-complex composition is not entirely known. Here, we report that the mouse utilizes Piezo1 (Pz1) and Piezo2 (Pz2) isoforms as MET-complex components. The Pz channels, expressed in HC stereocilia, and cell lines are co-localized and co-assembled with MET complex partners. Mice expressing non-functional Pz1 and Pz2 at the ROSA26 locus have impaired auditory and vestibular traits that can only be explained if the Pzs are integral to the MET complex. We suggest that Pz subunits constitute part of the MET complex and that interactions with other MET complex components yield functional MET units to generate HC MET currents., (© 2024. The Author(s).)

Nowadays, bee products are commended by consumers for their medicinal and dietary properties. This study aimed to differentiate between monofloral bee pollens originating from Portugal using phenolic and volatile profiles and investigate their antioxidant and cytotoxic activity. Total phenolic and flavonoid compounds were recorded between 2.9-35.8 mg GAE/g and 0.7-4.8 mg QE/g, respectively. The LC/DAD/ESI-MS n analytical results allowed us to identify and quantify a total of 72 compounds, including phenolic and phenylamide compounds, whereas GC-MS results revealed the presence of 49 different compounds, mostly ketones, aldehydes, esters, hydrocarbons, and terpenes. The highest DPPH • radical scavenging activity, EC 50 : 0.07 mg/mL, was recorded in the sample dominated by Castanae sp. pollen, whereas the Rubus sp. (1.59 mM Trolox/mg) and Cistaceae sp. (0.09 mg GAE/g) pollen species exhibited the highest antioxidant activity in ABTS •+ and reducing power assays, respectively. Regarding the anti-carcinogenic activity, only Carduus sp. showed remarkable cytotoxic potential against MCF-7.

ALECT2 systemic amyloidosis is associated with deposition of the leukocyte cell-derived chemotaxin-2 (LECT2) protein in the form of fibrils. In ALECT2 amyloidosis, ALECT2 fibrils deposit in the glomerulus, resulting in renal failure. Patients lack effective treatment options outside of renal transplant or dialysis. The structure of globular LECT2 has been determined but structures of ALECT2 amyloid fibrils remain unknown. Using single-particle cryo-EM, we find that recombinant human LECT2 forms robust twisting fibrils with canonical amyloid features. ALECT2 fibrils contain two mating protofilaments spanning residues 55-75 of the LECT2 sequence. The geometry of the ALECT2 fibril displays features in line with other pathogenic amyloids. Its core is tightly packed and stabilized by both hydrophobic contacts and hydrogen-bonded uncharged polar residues. The robustness of ALECT2 fibril cores is illustrated by their resistance to denaturants and proteases. This ALECT2 fibril structure presents a potential new target for treatments against ALECT2 systemic amyloidosis., Competing Interests: Declaration of interests J.A.R. is an equity stakeholder of MedStruc Inc., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Electron diffraction (MicroED/3DED) can render the three-dimensional atomic structures of molecules from previously unamenable samples. The approach has been particularly transformative for peptidic structures, where MicroED has revealed novel structures of naturally occurring peptides, synthetic protein fragments, and peptide-based natural products. Despite its transformative potential, MicroED is beholden to the crystallographic phase problem, which challenges its de novo determination of structures. ARCIMBOLDO, an automated, fragment-based approach to structure determination, eliminates the need for atomic resolution, instead enforcing stereochemical constraints through libraries of small model fragments, and discerning congruent motifs in solution space to ensure validation. This approach expands the reach of MicroED to presently inaccessible peptide structures including fragments of human amyloids, and yeast and mammalian prions. For electron diffraction, fragment-based phasing portends a more general phasing solution with limited model bias for a wider set of chemical structures., Competing Interests: The authors declare the following competing financial interest(s): J.A.R. is an equity stake holder of Medstruc, Inc., (© 2023 The Authors. Published by American Chemical Society.)

Hodgkin lymphoma (HL) appears to originate from germinal centre B cells but lacks expression of most B cell markers. In contrast to non-Hodgkin B lymphomas, HL is not routinely diagnosed using flow cytometry techniques, and diagnosis is mainly based on immunohistochemical and cytomorphological pathology studies. Hodgkin and Reed-Sternberg cells are large and fragile, making them difficult to study by flow cytometry. The aim of this study was to characterise the CD71 expression pattern on CD4+ T cells from HL patients and to design a simple flow cytometry algorithm to complement the histopathological diagnosis of HL. The present study suggests the utility of a conventional staining protocol with a simple panel of seven markers (CD15, CD30, CD4, CD8, CD71, CD3, and CD45) and a well-defined analysis strategy. The proposed algorithm uses the CD71 ratio (calculated as the percentage of CD71+ CD4+ T cells divided by the percentage of CD71+ CD45+ CD3- lymphocytes), with a cut-off of 0.5 to establish diagnosis groups as suggestive (≥0.5) or not suggestive (<0.5) of HL. In HL, CD71 expression is higher on CD4+ T lymphocytes than on non-T lymphocytes. In addition, the CD4+ T cell population is increased in HL patients, with no change in amounts of CD8+ T cells. Application of the CD71 ratio algorithm yielded a sensitivity of 82% and specificity of 87%, with 84.61% of patients correctly diagnosed. Although histopathology remains the gold standard for definitive HL diagnosis, the proposed flow cytometry method provides a rapid method to guide the study that would allow a more robust and integrated diagnosis. Moreover, the procedure is easily applicable in most clinical laboratories as it does not require state-of-the-art cytometers and uses standard reagents., (Copyright © 2022 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.)

Introduction: Pathogenic variants in the SLC26A2/DTDST gene cause the following spectrum of phenotypes: achondrogenesis 1B (ACG1B), atelosteogenesis 2 (AO2), diastrophic dysplasia (DTD), and recessive-multiple epiphyseal dysplasia (rMED), the first 2 being lethal. Here, we report a cohort and a comprehensive literature review on a genotype-phenotype correlation of SLC26A2/DTDST -related disorders., Methods: The local patients were genotyped by Sanger sequencing or next-generation sequencing (NGS). We reviewed data from the literature regarding phenotype, zygosity, and genotype in parallel., Results: The local cohort enrolled 12 patients, including one with a Desbuquois-like phenotype. All but one showed biallelic mutations, however, only one allele mutated in a fetus presenting ACG1B was identified. The literature review identified 42 articles and the analyses of genotype and zygosity included the 12 local patients., Discussion: The R279W variant was the most prevalent among the local patients. It was in homozygosity (hmz) in 2 patients with rMED and in compound heterozygosity (chtz) in 9 patients. The genotype and zygosity review of all patients led to the following conclusions: DTD is the most common phenotype in Finland due to a Finnish mutation (c.727-1G>C). Outside of Finland, rMED is the most prevalent phenotype, usually associated with R279W in hmz. In contrast, DTD's genotype is usually in chtz. Despite a large number of variants (38), just 8 are recurrent (R279W, C653S, c.-26+2T>C, R178*, K575Sfs*10, V340del, G663R, T512K). The last 3 in hmz lead to lethal phenotypes. The Finnish mutation is found only in chtz outside of Finland, being associated with all 4 classical phenotypes. The p.R178* and p.K575Sfs*10 variants should be viewed as lethal mutations since both were mainly described with lethal phenotypes and were never reported in hmz. The existence of 9 patients with only one mutated allele suggests that other mutations in the other allele of these patients still need to be unveiled., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2022 by S. Karger AG, Basel.)

Background: Cytochrome P4502E1 (CYP2E1) metabolizes environmental toxins, however, compound metabolism can produce oxidative stress, causing in-cell toxicity and sometimes transformation., Aim: To evaluate CYP2E1 gene expression and its effects in antioxidant defenses, and cell toxicity in printing workers., Methods: The hierarchical method of health and chemical risk was used to evaluate chemical exposure in workplace. Blood samples and buccal epithelial cells were obtained from printing workers, and workers without any history of occupational exposure to chemicals (control group). Gene expression of CYP2E1, and antioxidant enzymes Superoxide dismutase (SOD) and Catalase (CAT) from leukocytes were evaluated. Hematic analysis and cell-free DNA from plasma were analyzed. Frequencies of cells with micronuclei (MN) and nuclear abnormalities from buccal epithelial cells were explored., Results: Evaluation of chemical exposure in working place demonstrated that ethyl alcohol, isopropyl alcohol, and isophorone represent 91% of the accumulated potential risk. CYP2E1 expression showed a 2.5-fold overexpression in the printing workers compared to the control group. SOD expression showed a 0.5-fold lower level in the printing workers than the control group, and CAT expression showed no differences between groups. Lower red blood cell and platelet values were detected in the printing workers than in the control group, and cell-free DNA plasma concentration was 3-fold higher in the printing workers than in the control group. The printing workers showed a higher frequency of cells with MN and nuclear anomalies than the control group., Conclusion: CYP2E1 overexpression triggers antioxidant defenses and toxic cell effects in printing workers.

Despite stringent selection criteria, hepatocellular carcinoma recurrence after liver transplantation (LT) still occurs in up to 20% of cases, mostly within the first 2-3 years. No adjuvant treatments to prevent such an occurrence have been developed so far. However, a balanced use of immunosuppression with minimal dose of calcineurin inhibitors and possible addition of mammalian target of rapamycin inhibitors is strongly advisable. Moreover, several pre- and post-transplant predictors of recurrence have been identified and may help determine the frequency and duration of post-transplant follow-up. When recurrence occurs, the outcomes are poor with a median survival of 12 mo according to most retrospective studies. The factor that most impacts survival after recurrence is timing (within 1-2 years from LT according to different authors). Several therapeutic options may be chosen in case of recurrence, according to timing and disease presentation. Surgical treatment seems to provide a survival benefit, especially in case of late recurrence, while the benefit of locoregional treatments has been suggested only in small retrospective studies. When systemic treatment is indicated, sorafenib has been proved safe and effective, while only few data are available for lenvatinib and regorafenib in second line. The use of immune checkpoint inhibitors is controversial in this setting, given the safety warnings for the risk of acute rejection., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Among the features of cisplatin chemotherapy-induced peripheral neuropathy are chronic pain and innocuous mechanical hypersensitivity. The complete etiology of the latter remains unknown. Here, we show that cisplatin targets a heterogeneous population of tyrosine hydroxylase-positive (TH + ) primary afferent dorsal root ganglion neurons (DRGNs) in mice, determined using single-cell transcriptome and electrophysiological analyses. TH + DRGNs regulate innocuous mechanical sensation through C-low threshold mechanoreceptors. A differential assessment of wild-type and vitamin E deficient TH + DRGNs revealed heterogeneity and specific functional phenotypes. The TH + DRGNs comprise; fast-adapting eliciting one action potential (AP; 1-AP), moderately-adapting (≥2-APs), in responses to square-pulse current injection, and spontaneously active (SA). Cisplatin increased the input resistance and AP frequency but reduced the temporal coding feature of 1-AP and ≥2-APs neurons. By contrast, cisplatin has no measurable effect on the SA neurons. Vitamin E reduced the cisplatin-mediated increased excitability but did not improve the TH + neuron temporal coding properties. Cisplatin mediates its effect by targeting outward K + current, likely carried through K2P18.1 (Kcnk18 ), discovered through the differential transcriptome studies and heterologous expression. Studies show a potential new cellular target for chemotherapy-induced peripheral neuropathy and implicate the possible neuroprotective effects of vitamin E in cisplatin chemotherapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Finno, Chen, Park, Lee, Perez-Flores, Choi and Yamoah.)

Mechanosensation - by which mechanical stimuli are converted into a neuronal signal - is the basis for the sensory systems of hearing, balance, and touch. Mechanosensation is unmatched in speed and its diverse range of sensitivities, reaching its highest temporal limits with the sense of hearing; however, hair cells (HCs) and the auditory nerve (AN) serve as obligatory bottlenecks for sounds to engage the brain. Like other sensory neurons, auditory neurons use the canonical pathway for neurotransmission and millisecond-duration action potentials (APs). How the auditory system utilizes the relatively slow transmission mechanisms to achieve ultrafast speed, and high audio-frequency hearing remains an enigma. Here, we address this paradox and report that the mouse, and chinchilla, AN are mechanically sensitive, and minute mechanical displacement profoundly affects its response properties. Sound-mimicking sinusoidal mechanical and electrical current stimuli affect phase-locked responses. In a phase-dependent manner, the two stimuli can also evoke suppressive responses. We propose that mechanical sensitivity interacts with synaptic responses to shape responses in the AN, including frequency tuning and temporal phase locking. Combining neurotransmission and mechanical sensation to control spike patterns gives the mammalian AN a secondary receptor role, an emerging theme in primary neuronal functions., Competing Interests: MP, EV, JL, HK, PJ, EY No competing interests declared, (© 2022, Perez-Flores et al.)

Cholangiocarcinoma is the second most common primary tumor of the liver. The incidence and mortality of its intrahepatic form has been increasing over the past 2 decades. Currently, the only available curative treatment for intrahepatic cholangiocarcinoma is surgical resection. There is still no prospective evidence to support neoadjuvant systemic treatments in resectable disease, while adjuvant chemotherapy with Capecitabine is currently the only recommended systemic treatment after liver resection based on the results of randomised trial. Despite the implementation of perioperative treatments and improvements in resective surgery, intrahepatic cholangiocarcinoma remains a disease characterized by high incidence of recurrence and poor long-term survival. Lymph node metastases can be found in 45-65% of patients and are one of the most impacting prognostic factors after surgical resection. Preoperative imaging is not always sufficient in assessing lymph node status, thus hepatic pedicle lymphadenectomy can be important to ensure precise staging in surgical patients. An increasing trend in performing lymph node dissection during liver resection for intrahepatic cholangiocarcinoma has been observed in the last 20 years, although its actual efficacy compared to the potential complications remains debated. The current evidence on the prognostic role of the lymph node status, its preoperative predictability, the basis for a correct hepatic pedicle lymphadenectomy and its prognostic role in the surgical treatment of intrahepatic cholangiocarcinoma are presented., Competing Interests: Declaration of competing interest Authors declare no conflict of interests for this article., (Copyright © 2021 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)

The COVID-19 pandemic brought about a global crisis affecting all sectors of society. Higher education is no exception. The closure of higher education institutions has dictated a sudden and unexpected transition from face-to-face to remote teaching to mitigate the spread of the SARS-CoV-2. This paper draws upon a wider piece of research which aimed to understand how higher education students adapted to the closure of their institution and how they looked at their experience of online teaching and learning. In total, 2718 students from different Portuguese higher education institutions participated in the study. Findings showed that both personal and contextual factors explained students' positive or negative adaptation to online teaching and learning as a result of the closure of higher education institutions. Institutional and pedagogical responses, individual self-regulatory and socio-emotional competencies and adequate resources were factors that led to either a more positive or negative student experience of online teaching and learning in times of COVID-19., (© The Author(s), under exclusive licence to Springer Nature B.V. 2021.)

Most patients with cystic fibrosis (CF) develop multisystemic clinical manifestations, the minority having mild or atypical symptoms. We describe an adolescent with chronic cough and purulent rhinorrhoea since the first year of life, with diagnoses of asthma, allergic rhinitis and chronic rhinosinusitis. Under therapy with long-acting bronchodilators, antihistamines, inhaled corticosteroids, antileukotrienes and several courses of empirical oral antibiotic therapy, there was no clinical improvement. There was no reference to gastrointestinal symptoms. Due to clinical worsening, extended investigations were initiated, which revealed Pseudomonas aeruginosa in sputum culture, sweat test with a positive result and heterozygosity for F508del and R334W mutations in genetic study which allowed to confirm the diagnosis of CF. In this case, heterozygosity with a class IV mutation can explain the atypical clinical presentation. It is very important to consider this diagnosis when chronic symptoms persist, despite optimised therapy for other respiratory pathologies and in case of isolation of atypical bacterial agents., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Objectives: The ESSPRI is a validated tool for measuring pain, fatigue and dryness in primary Sjögren's syndrome (pSS). We evaluated its association with disease and non-disease related variables, and its variation though the follow-up., Methods: We included 130 pSS patients who were interviewed to register demographics, schooling, smoking, menopause, body mass index (BMI), disease duration, use of hormonal replacement, associated sicca drugs, prednisone, immunosuppressors/antimalarials, comorbidities such as diabetes mellitus, hypothyroidism, depression, fibromyalgia and scored the Charlson comorbidity index. We assessed the non-stimulated whole salivary flow (NSWSF), Schirmer-I test, ESSDAI and ESSPRI scores. In a subset of patients, we scored a second ESSPRI., Results: Most patients were women, mean age 57 years and median disease duration 9.3 years. The median ESSPRI score was 6 (fatigue 6, pain 4, dryness 8). Eighty patients (61.5%) had an ESSPRI ≥5 points and were characterized by a higher prevalence of depression (OR 3.7, 95% 1.2-11.3) and lower NSWSF (OR 0.59, 95% CI 0.36-0.97). Among 62 patients with a second ESSPRI (median time 25 months), 44 (70%) experienced a decrement/increment ≥1 in the ESSPRI (16 were decrement). We did not find any of the studied variables associated with this variation, also including change in prednisone or immunosuppressors., Conclusions: An ESSPRI ≥5 (unsatisfactory symptom state) was associated with low NSWSF and depression. Most of the patients experienced a clinically significant ESSPRI variation (increment or decrement), nevertheless, we were not able to identify any variable associated with this change. Further studies would be helpful to understand the underlying causes.

Prestin (Slc26a5) is a motor protein previously considered to be expressed exclusively in outer hair cells (OHCs) of the inner ear. However, we recently identified the functional expression of prestin in the heart. Nonlinear capacitance (NLC) measurement in OHCs is used to evaluate the signature function of prestin, which exhibits membrane potential-dependent conformational changes. Here, we describe detailed recording techniques and quantification methods for NLC to evaluate the prestin function in mouse ventricular myocytes. For complete details on the use and execution of this protocol, please refer to Zhang et al. (2021)., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)

The center stage of neuro-imaging is currently occupied by studies of functional correlations between brain regions. These correlations define the brain functional networks, which are the most frequently used framework to represent and interpret a variety of experimental findings. In the previous study, we first demonstrated that the relatively stronger blood oxygenated level dependent (BOLD) activations contain most of the information relevant to understand functional connectivity, and subsequent work confirmed that a large compression of the original signals can be obtained without significant loss of information. In this study, we revisit the correlation properties of these epochs to define a measure of nonlinear dynamic directed functional connectivity ( nldFC ) across regions of interest. We show that the proposed metric provides at once, without extensive numerical complications, directed information of the functional correlations, as well as a measure of temporal lags across regions, overall offering a different and complementary perspective in the analysis of brain co-activation patterns. In this study, we provide further details for the computations of these measures and for a proof of concept based on replicating existing results from an Autistic Syndrome database, and discuss the main features and advantages of the proposed strategy for the study of brain functional correlations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cifre, Miller Flores, Penalba, Ochab and Chialvo.)

Background: Leiomyosarcomas (LMS) of the inferior vena cava (IVC) originate in the retrohepatic (RHVC) portion in 15% of cases.1 Due to complex anatomy and need to preserve venous outflow from the infra-diaphragmatic viscera, the operation may require total vascular exclusion, veno-venous bypass and hypothermic liver resections.2,3 In this video, virtual planning of the operation allowed a parenchyma-sparing radical resection in a patient with limited liver reserve., Methods: A 12-cm LMS of RHVC invading the entire segment 1 (i.e., Spiegel's lobe, paracaval portion, and caudate process) was diagnosed in a man with metabolic steato-hepatitis (BMI: 34). He had no response to previous chemotherapy. Major hepatectomy was excluded considering the high risk of postoperative liver failure. 3D-reconstruction of regional anatomy allowed planning of a parenchymal-sparing, en bloc resection of tumor, RHVC, and caudate lobe while avoiding hilar and suprahepatic venous clamping., Results: The operation strategy relied on the en bloc separation of caudate lobe, RHVC, and tumor from the hepatic veins confluence and the posterior segments after complete mobilization of the liver. Vessel loop-assisted hanging maneuver, encircling tumor, and RHVC with superimposed 3D-reconstructions guided the parenchymal transection, while preserving the middle hepatic vein outflow. RHVC was replaced with prosthetic material., Conclusions: Complex resection of primary tumor of the IVC en bloc with caudate lobe and RHVC can be attempted in chronic liver diseases at-risk of postoperative failure. Preservations of transhepatic flow and liver function depends on tumor size and preservation of noninvaded hepatic-veins confluence. Preoperative virtual 3D reconstruction is crucial in surgical planning., (© 2021. The Author(s).)

Molecular diagnosis is important to provide accurate genetic counseling of skeletal dysplasias (SD). Although next-generation sequencing (NGS) techniques are currently the preferred methods for analyzing these conditions, some of the published results have not shown a detection rate as high as it would be expected. The present study aimed to assess the diagnostic yield of targeted NGS combined with Sanger sequencing (SS) for low-coverage exons of genes of interest and exome sequencing (ES) in a series of patients with rare SD and use two patients as an example of our strategy. This study used two different in-house panels. Of 93 variants found in 88/114 (77%) patients, 57 are novel. The pathogenic variants found in the following genes: B3GALT6, PCYT1A, INPPL1, LIFR, of four patients were only detected by SS. In conclusion, the high diagnostic yield reached in the present study can be attributed to both a good selection of patients and the utilization of the SS for the insufficiently covered regions. Additionally, the two case reports-a patient with acrodysostosis related to PRKAR1A and another with ciliopathy associated with KIAA0753, add new and relevant clinical information to the current knowledge., (© 2021 Wiley Periodicals LLC.)

Pathogenic clade B New World mammarenaviruses (NWM) can cause Argentine, Venezuelan, Brazilian, and Bolivian hemorrhagic fevers. Sequence variability among NWM glycoproteins (GP) poses a challenge to the development of broadly neutralizing therapeutics against the entire clade of viruses. However, blockade of their shared binding site on the apical domain of human transferrin receptor 1 (hTfR1/CD71) presents an opportunity for the development of effective and broadly neutralizing therapeutics. Here, we demonstrate that the murine monoclonal antibody OKT9, which targets the apical domain of hTfR1, can sterically block cellular entry by viral particles presenting clade B NWM glycoproteins (GP1-GP2). OKT9 blockade is also effective against viral particles pseudotyped with glycoproteins of a recently identified pathogenic Sabia-like virus. With nanomolar affinity for hTfR1, the OKT9 antigen binding fragment (OKT9-Fab) sterically blocks clade B NWM-GP1s and reduces infectivity of an attenuated strain of Junin virus. Binding of OKT9 to the hTfR1 ectodomain in its soluble, dimeric state produces stable assemblies that are observable by negative-stain electron microscopy. A model of the OKT9-sTfR1 complex, informed by the known crystallographic structure of sTfR1 and a newly determined structure of the OKT9 antigen binding fragment (Fab), suggests that OKT9 and the Machupo virus GP1 share a binding site on the hTfR1 apical domain. The structural basis for this interaction presents a framework for the design and development of high-affinity, broadly acting agents targeting clade B NWMs. IMPORTANCE Pathogenic clade B NWMs cause grave infectious diseases, the South American hemorrhagic fevers. Their etiological agents are Junin (JUNV), Guanarito (GTOV), Sabiá (SABV), Machupo (MACV), Chapare (CHAV), and a new Sabiá-like (SABV-L) virus recently identified in Brazil. These are priority A pathogens due to their high infectivity and mortality, their potential for person-to-person transmission, and the limited availability of effective therapeutics and vaccines to curb their effects. While low homology between surface glycoproteins of NWMs foils efforts to develop broadly neutralizing therapies targeting NWMs, this work provides structural evidence that OKT9, a monoclonal antibody targeting a single NWM glycoprotein binding site on hTfR1, can efficiently prevent their entry into cells.

Background: Bile leaks occurring after complex liver resection and lasting >1 week (grade B) usually are managed by means of invasive cholangiography either endoscopic or percutaneous, with a substantial risk of procedure-related complications. The aim of this study was to investigate the ability of gadoxetic acid disodium-enhanced magnetic resonance cholangiography to detect postoperative biliary leaks and avoid invasive cholangiography in case of peripheral location of the fistula., Methods: Patients with grade B biliary leak after complex liver resection from January 2018 to March 2020 underwent magnetic resonance cholangiography to guide the management of the leak (study group). The primary endpoint was the ability of magnetic resonance cholangiography to reduce the need for invasive cholangiography with respect to similar posthepatectomy leaks collected in the previous 2 years and approached with upfront invasive cholangiography (controls). A series of in-hospital outcomes also were compared., Results: Out of 533 liver resections, 11 study patients versus 11 control patients with grade B leaks were compared. Magnetic resonance cholangiography achieved 100% accuracy in detection and location of the leak. Five out of 6 peripheral leaks healed without invasive cholangiography. Overall, 50% reduction in the use of invasive cholangiography was observed in the study versus control patients. Median healing time and hospital stay were 38 and 40 days in patients undergoing invasive cholangiography versus 10 and 11 days in patients treated conservatively (P = .007 and 0.012, respectively). Infection rate and other complications rate were 82% vs 20% (P = .01) and 35% vs 40% (P = .5), respectively., Conclusion: Magnetic resonance cholangiography is a safe, precise, noninvasive tool to detect posthepatectomy bile leaks that can help clinicians in decision-making on conservative versus invasive treatment of fistulas., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The mTORC1 node plays a major role in autophagy modulation. We report a role of the ubiquitous Gαq subunit, a known transducer of plasma membrane G protein-coupled receptors signaling, as a core modulator of mTORC1 and autophagy. Cells lacking Gαq/11 display higher basal autophagy, enhanced autophagy induction upon different types of nutrient stress along with a decreased mTORC1 activation status. They are also unable to reactivate mTORC1 and thus inactivate ongoing autophagy upon nutrient recovery. Conversely, stimulation of Gαq/11 promotes sustained mTORC1 pathway activation and reversion of autophagy promoted by serum or amino acids removal. Gαq is present in autophagic compartments and lysosomes and is part of the mTORC1 multi-molecular complex, contributing to its assembly and activation via its nutrient status-sensitive interaction with p62, which displays features of a Gαq effector. Gαq emerges as a central regulator of the autophagy machinery required to maintain cellular homeostasis upon nutrient fluctuations., (© 2021. The Author(s).)

Cardiac cells generate and amplify force in the context of cardiac load, yet the membranous sheath enclosing the muscle fibers-the sarcolemma-does not experience displacement. That the sarcolemma sustains beat-to-beat pressure changes without experiencing significant distortion is a muscle-contraction paradox. Here, we report that an elastic element-the motor protein prestin (Slc26a5)-serves to amplify actin-myosin force generation in mouse and human cardiac myocytes, accounting partly for the nonlinear capacitance of cardiomyocytes. The functional significance of prestin is underpinned by significant alterations of cardiac contractility in Prestin-knockout mice. Prestin was previously considered exclusive to the inner ear's outer hair cells; however, our results show that prestin serves a broader cellular motor function., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Within the past decades, major progress has been accomplished in isolating germ/stem/pluripotent cells, in refining culture medium and conditions and in establishing 3-dimensional culture systems, towards developing organoids for organs involved in reproduction in mice and to some extent in humans. Haploid male germ cells were generated in vitro from primordial germ cells. So were oocytes, with additional support from ovarian cells and subsequent follicle culture. Going on with the female reproductive tract, spherical oviduct organoids were obtained from adult stem/progenitor cells. Multicellular endometrial structures mimicking functional uterine glands were derived from endometrial cells. Trophoblastic stem cells were induced to form 3-dimensional syncytial-like structures and exhibited invasive properties, a crucial point for placentation. Finally, considering the embryo itself, pluripotent embryonic cells together with additional extra-embryonic cells, could self-organize into a blastoid, and eventually into a post-implantation-like embryo. Most of these accomplishments have yet to be reached in farm animals, but much effort is devoted towards this goal. Here, we review the progress and discuss the specific challenges of developing organoids for the study of reproductive biology in these species. We consider the use of such organoids in basic research to delineate the physiological mechanisms involved at each step of the reproductive process, or to understand how they are altered by environmental factors relevant to animal breeding. We evaluate their potential in reproduction of animals with a high genetic value, from a breeding point of view or in the context of preserving local breeds with limited headcounts.

Skeletal dysplasias (SD) are disturbances in growth due to defects intrinsic to the bone and/or cartilage, usually affecting multiple bones and having a progressive character. In this article, we review the state of clinical and research SD resources available in Latin America, including three specific countries (Brazil, Argentina, and Chile), that have established multidisciplinary clinics for the care of these patients. From the epidemiological point of view, the SD prevalence of 3.2 per 10,000 births from nine South American countries included in the ECLAMC network represents the most accurate estimate not just in Latin America, but worldwide. In Brazil, there are currently five groups focused on SD. The data from one of these groups including the website www.ocd.med.br, created to assist in the diagnosis of SD, are highlighted showing that telemedicine for this purpose represents a good strategy for the region. The experience of more than 30 years of the SD multidisciplinary clinic in an Argentinian Hospital is presented, evidencing a solid experience mainly in the follow-up of the most frequent SD, especially those belonging the FGFR3 group and OI. In Chile, a group with 20 years of experience presents its work with geneticists and pediatricians, focusing on diagnostic purposes and clinical management. Altogether, although SD health-care and research activities in Latin America are in their early stages, the experience in these three countries seems promising and stimulating for the region as a whole., (© 2020 Wiley Periodicals LLC.)

The novel COVID-19, detected in Wuhan, China, has reached almost every city across the globe, and researchers from many countries have used several epidemiologic models to describe the epidemic trends. In this context, it is also important to know the geographic extent of the infected population. Following this approach, a Gumpertz model was adapted with official data from the state of Hidalgo, Mexico, in order to estimate the people infected during this COVID-19 pandemic. We found, based on the adjusted data, the highest value in infected people according to official and theoretical data. Furthermore, using a geographical analysis based on geostatistical measures related to density of demographic and economic data, traffic level and geolocation, raster files were generated to estimate probability of coronavirus cases occurrence using the areas where the contagion may occur. We also distributed the maximum contagion obtained by the epidemic model, using these raster files, and a regression model to weight factors according their importance. Based on this estimated distribution, we found that most of the infected people were located in the southern border, a trend related to the economic strip in the southern part of Hidalgo State, associated with its vicinity to the Megacity of Mexico.

Organelle crosstalk is vital for cellular functions. The propinquity of mitochondria, ER, and plasma membrane promote regulation of multiple functions, which include intracellular Ca 2+ flux, and cellular biogenesis. Although the purposes of apposing mitochondria and ER have been described, an understanding of altered organelle connectomics related to disease states is emerging. Since inner ear outer hair cell (OHC) degeneration is a common trait of age-related hearing loss, the objective of this study was to investigate whether the structural and functional coupling of mitochondria with subsurface cisternae (SSC) was affected by aging. We applied functional and structural probes to equal numbers of male and female mice with a hearing phenotype akin to human aging. We discovered the polarization of cristae and crista junctions in mitochondria tethered to the SSC in OHCs. Aging was associated with SSC stress and decoupling of mitochondria with the SSC, mitochondrial fission/fusion imbalance, a remarkable reduction in mitochondrial and cytoplasmic Ca 2+ levels, reduced K + -induced Ca 2+ uptake, and marked plasticity of cristae membranes. A model of structure-based ATP production predicts profound energy stress in older OHCs. This report provides data suggesting that altered membrane organelle connectomics may result in progressive hearing loss., Competing Interests: The authors declare no competing financial interests., (Copyright © 2020 the authors.)

The synthesis of graphene nanoribbons (GNRs) that contain site-specifically substituted backbone heteroatoms is one of the essential goals that must be achieved in order to control the electronic properties of these next generation organic materials. We have exploited our recently reported solid-state topochemical polymerization/cyclization-aromatization strategy to convert the simple 1,4-bis(3-pyridyl)butadiynes 3a,b into the fjord-edge nitrogen-doped graphene nanoribbon structures 1a,b (fjord-edge N 2 [8]GNRs). Structural assignments are confirmed by CP/MAS 13 C NMR, Raman, and XPS spectroscopy. The fjord-edge N 2 [8]GNRs 1a,b are promising precursors for the novel backbone nitrogen-substituted N 2 [8] A GNRs 2a,b . Geometry and band calculations on N 2 [8] A GNR 2c indicate that this class of nanoribbons should have unusual bonding topology and metallicity.

The skin is the largest organ in the human body, providing a barrier to the external environment. It is composed of three layers: epidermis, dermis and hypodermis. The most external epidermis is exposed to stress factors that may lead to skin conditions such as photo-aging and skin cancer. Some treatments for skin disease utilize the incorporation of drugs or bioactive compounds into nanocarriers known as liposomes. Liposomes are membranes whose sizes range from nano to micrometers and are composed mostly of phospholipids and cholesterol, forming similar structures to cell membranes. Thus, skin treatments with liposomes have lower toxicity in comparison to traditional treatment routes such as parenteral and oral. Furthermore, addition of edge activators to the liposomes decreases the rigidity of the bilayer structure making it deformable, thereby improving skin permeability. Liposomes are composed of an aqueous core and a lipidic bilayer, which confers their amphiphilic property. Thus, they can carry hydrophobic and hydrophilic compounds, even simultaneously. Current applications of these nanocarriers are mainly in the cosmetic and pharmaceutic industries. Nevertheless, new research has revealed promising results regarding the effectiveness of liposomes for transporting bioactive compounds through the skin. Liposomes have been well studied; however, additional research is needed on the efficacy of liposomes loaded with bioactive peptides for skin delivery. The objective of this review is to provide an up-to-date description of existing techniques for the development of liposomes and their use as transporters of bioactive compounds in skin conditions such as melanoma and skin inflammation. Furthermore, to gain an understanding of the behavior of liposomes during the process of skin delivery of bioactive compounds into skin cells., Competing Interests: The authors report no conflicts of interest for this work., (© 2020 Castañeda-Reyes et al.)

Bioglass nanoparticles (n-BGs, 54SiO 2 :40CaO:6P 2 O 5 mol %) with about 27 nm diameter were synthesized by the sol-gel method and incorporated into a poly(lactic acid) (PLA) matrix by the melting process in order to obtain nanocomposites with filler contents of 5, 10, and 25 wt %. Our results showed that during the cooling scan, the crystallization temperature (T c ) of the PLA/n-BG nanocomposites decreased 13°C as compared to neat PLA. The presence of nanoparticles also decreased the thermal stability of the PLA matrix, as nanocomposites presented up to about 20°C lower degradation temperatures in a nitrogen atmosphere. The presence of n-BG increased the stiffness of the polymer matrix, and for instance the composite with 25 wt % of filler presented about 52.6% higher Young's modulus than neat PLA. n-BG incorporation into PLA increased also the hydrolytic degradation of the polymer over time. When the PLA composites were immersed in simulated body fluid, an apatite layer was formed on their surface, as verified by Fourier transform infrared, X-Ray Diffraction (XRD), and scanning electron microscopy-EDS, showing that the presence of n-BG induced bioactivity on the PLA matrix. Moreover, the viability of cervical uterine adenocarcinoma cells was higher on PLA/n-BG nanocomposite with 25 wt % of filler. The presence of n-BG barely gave an antibacterial effect on the polymer matrix, despite the well-known biocidal properties of these nanoparticles. Our results show that the presence of n-BGs is a proper route for improving the bioactivity of PLA with potential application in tissue engineering., (© 2020 Wiley Periodicals, Inc.)

Background: Indications for liver transplantation for hepatocellular carcinoma are evolving and so-called expanded criteria remain debated. Locoregional therapies are able to downstage hepatocellular carcinoma from beyond to within the Milan criteria. We aimed to investigate the efficacy of liver transplantation after successful hepatocellular carcinoma downstaging., Methods: We did an open-label, multicentre, randomised, controlled trial designed in two phases, 2b and 3, at nine Italian tertiary care and transplantation centres. Patients aged 18-65 years with hepatocellular carcinoma beyond the Milan criteria, absence of macrovascular invasion or extrahepatic spread, 5-year estimated post-transplantation survival of at least 50%, and good liver function (Child-Pugh A-B7) were recruited and underwent tumour downstaging with locoregional, surgical, or systemic therapies according to multidisciplinary decision. After an observation period of 3 months, during which sorafenib was allowed, patients with partial or complete responses according to modified Response Evaluation Criteria in Solid Tumors were randomly assigned (1:1) by an interactive web-response system to liver transplantation or non-transplantation therapies (control group). A block randomisation (block size of 2), stratified by centre and compliance to sorafenib treatment, was applied. Liver transplantation was done with whole or split organs procured from brain-dead donors. The control group received sequences of locoregional and systemic treatment at the time of demonstrated tumour progression. The primary outcomes were 5-year tumour event-free survival for phase 2b and overall survival for phase 3. Analyses were by intention to treat. Organ allocation policy changed during the course of the study and restricted patient accrual to 4 years. This trial is registered with ClinicalTrials.gov, NCT01387503., Findings: Between March 1, 2011, and March 31, 2015, 74 patients were enrolled. Median duration of downstaging was 6 months (IQR 4-11). 29 patients dropped out before randomisation and 45 were randomly assigned: 23 to the transplantation group versus 22 to the control group. At data cutoff on July 31, 2019, median follow-up was 71 months (IQR 60-85). 5-year tumour event-free survival was 76·8% (95% CI 60·8-96·9) in the transplantation group versus 18·3% (7·1-47·0) in the control group (hazard ratio [HR] 0·20, 95% CI 0·07-0·57; p=0·003). 5-year overall survival was 77·5% (95% CI 61·9-97·1) in the transplantation group versus 31·2% (16·6-58·5) in the control group (HR 0·32, 95% CI 0·11-0·92; p=0·035). The most common registered grade 3-4 serious adverse events were hepatitis C virus recurrence (three [13%] of 23 patients) and acute transplant rejection (two [9%]) in the transplantation group, and post-embolisation syndrome (two [9%] of 22 patients) in the control group. Treatment-related deaths occurred in four patients: two (8%) of 23 patients in the transplantation group (myocardial infarction and multi-organ failure) versus two (9%) of 22 patients in the control group (liver decompensation)., Interpretation: Although results must be interpreted with caution owing to the early closing of the trial, after effective and sustained downstaging of eligible hepatocellular carcinomas beyond the Milan criteria, liver transplantation improved tumour event-free survival and overall survival compared with non-transplantation therapies Post-downstaging tumour response could contribute to the expansion of hepatocellular carcinoma transplantation criteria., Funding: Italian Ministry of Health., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The mammalian cochlea relies on active electromotility of outer hair cells (OHCs) to resolve sound frequencies. OHCs use ionic channels and somatic electromotility to achieve the process. It is unclear, though, how the kinetics of voltage-gated ionic channels operate to overcome extrinsic viscous drag on OHCs at high frequency. Here, we report ultrafast electromechanical gating of clustered K v 7.4 in OHCs. Increases in kinetics and sensitivity resulting from cooperativity among clustered-K v 7.4 were revealed, using optogenetics strategies. Upon clustering, the half-activation voltage shifted negative, and the speed of activation increased relative to solitary channels. Clustering also rendered K v 7.4 channels mechanically sensitive, confirmed in consolidated K v 7.4 channels at the base of OHCs. K v 7.4 clusters provide OHCs with ultrafast electromechanical channel gating, varying in magnitude and speed along the cochlea axis. Ultrafast K v 7.4 gating provides OHCs with a feedback mechanism that enables the cochlea to overcome viscous drag and resolve sounds at auditory frequencies., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)