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Acini are essential for the secretory function of multiple exocrine organs. During acini formation, a cluster of epithelial end bud progenitors must undergo secretory program initiation, maturation and cell polarization to form a unit of single layered secretory cells enclosing a central lumen. Yet, how this complex process is regulated remains unknown. Using the developing salivary gland as a model, we reveal the EGF receptor ERBB3 as a master driver of acinus formation. We discovered ERBB3 to be enriched in end buds, and through conditional deletion of epithelial Erbb3, to be essential in multiple steps of secretory cell program initiation, cell maturation, expansion and polarization. Moreover, we demonstrate that addition of a single factor, ERBB3 ligand neuregulin-1, to isolated epithelia ex vivo is sufficient to recapitulate the complex outcomes of in vivo acinus formation in multiple exocrine organs. Finally, we reveal a new ERBB3-mTOR1/2 signaling link that governs the full formation of the secretory acinus.

Breast cancer is the most common type of cancer in the world. The aggressive and invasive nature of these tumors is explicable by the presence of cancer stem cells, which have self-renewal and initiation potentials that are analogous to the capabilities seen in normal mammary stem cells. The characterization of a protein’s role in a normal mammary gland, along with how this function is altered in cancerous tissue, enables enhanced understanding of the potential for specific novel drug targets. Transcription factor EB (TFEB) is currently known for its role as a master lysosomal regulator, and it has been shown to assist with cancerous progression through metabolic reprogramming. Yet, the key functions served by TFEB in mammary acini formation and its effects on mammary stem cells have never been determined. I have shown that the silencing of TFEB interrupts and disorganizes the development of mammary acini, unlike mere transcriptional inactivation. Furthermore, TFEB was not found to directly regulate the differentiation of mammary stem cells into a luminal lineage. Instead, TFEB appears to markedly contribute to the early proliferation of MCF10A cells, but additional investigation is necessary to characterize the mechanism. This work will guide future exploration into TFEB's potential as a drug target.

Background/aim The aim of this study was to investigate the administration of cinnamon extract that is known to be effective in decreasing the high blood glucose and the distribution of NGF and Trk-A receptor in pancreas with immunohistochemistry way. Materials and methods The experimental groups were defined as control, sham, cinnamon, diabetes, and diabetes-cinnamon. At the end of the experiment, the pancreatic tissue samples were obtained for the rats. The hematoxylin-eosin and triple staining were used to examine histology. The immunohistochemical methods were performed on the sections of pancreatic tissue. In all groups, the body weight and fasting blood glucose obtained from the male and female rats and the values were statistically evaluated. Results The NGF immunoreactivity was observed in acinus, excretory pars, excretorius ducts, and islets of Langerhans for the pancreatic tissues of female and male rats in all groups. The Trk-A immunoreactivity was observed in acinus and islets of Langerhans for the pancreatic tissues of female and male rats in the control, sham, and cinnamon groups. Conclusion As a result, it was determined that the cinnamon, which is effective on blood glucose levels, has a positive effect on the NGF production in pancreas.

This study analyzes the dimensional changes of the glands from prostate cancer by applying stereology to estimate the variations in volume, length, surface, and cellular densities of tumor acini. Normal and tumor acini were visualized using immunohistochemistry for cytokeratin18. On immunostained sections, parameters related to the dimensions and cell population of prostate acini were measured. The immunohistochemical expression of proliferative cell nuclear antigen was also measured to correlate the quantitative changes estimated with the proliferative activity of the epithelium. The average cell volume in normal and tumor epithelium was estimated using the method of the nucleator. The relative size of the acini was similar in the carcinoma compared with the normal prostate. Within the acini, the fraction of acinar volume occupied by the epithelium was significantly higher in cancer than in the nontumor prostate. Conversely, the glandular lumen of the cancer acini is lower than in the normal acini. The significant increase of acinar length density in the carcinoma indicates that the glandular tree's growth in the carcinoma is higher and with more branches than in the case of nonneoplastic glands. The basal surface density is higher in the carcinoma than in the controls. The number of epithelial cells per unit length of acini was significantly decreased in the neoplastic glands. This "dilution" of the cell population along the cancer acinus can be explained by the significant increase in the tumor cell's mean cell volume.

The spermatogenesis of adult snail Eobania vermiculata was investigated using transmission electron microscope (TEM) studies. The hermaphrodite gland (ovotestis) is composed of many lobes which have numerous acini. Each acinus was filled with many stages of spermatogenesis and one or more oocytes. The oocytes were usually separated from the rest of the acinus by follicle cells. Spermatogenesis is divided into 5 stages; spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, and spermatozoa. The gonadal somatic cells; Sertoli cells are divided into two types, cortical Sertoli cells, and luminal Sertoli cells.

Acinar cells are the principal secretory units of multiple exocrine organs. A single-cell, layered, lumenized acinus forms from a large cohort of epithelial progenitors that must initiate and coordinate three cellular programs of acinar specification, namely, lineage progression, secretion, and polarization. Despite this well-known outcome, the mechanism(s) that regulate these complex programs are unknown. Here, we demonstrate that neuronal-epithelial cross-talk drives acinar specification through neuregulin (NRG1)-ERBB3-mTORC2 signaling. Using single-cell and global RNA sequencing of developing murine salivary glands, we identified NRG1-ERBB3 to precisely overlap with acinar specification during gland development. Genetic deletion of Erbb3 prevented cell lineage progression and the establishment of lumenized, secretory acini. Conversely, NRG1 treatment of isolated epithelia was sufficient to recapitulate the development of secretory acini. Mechanistically, we found that NRG1-ERBB3 regulates each developmental program through an mTORC2 signaling pathway. Thus, we reveal that a neuronal-epithelial (NRG1/ERBB3/mTORC2) mechanism orchestrates the creation of functional acini.

Purpose. Identification of the possibilities of contrast enhancement computed tomography in evaluated the number of the acinar structures in the pancreatic parenchyma at the preoperative stage to predict the development pancreatic fistula.Material and methods. In 2016–2019, 196 pancreatoduodenectomy were performed. 86 patients were retrospectively selected. Patients were divided into 2 groups: group 1 included 16 observations with the development of clinically significant pancreatic fistula, in 2 – 70 cases without complications. According to preoperative contrast enhancement computed tomography, structure of the pancreas, pancreatic parenchyma thickness, pancreatic duct diameter, the density of the pancreas in the native phase, relative parenchyma enhancement ratio, washout coefficient, pancreas stump volume were evaluated. According histological, the number of acinar and fat cells in the section of the removed pancreas was evaluated.Results. “Soft” structure of the pancreas (r = 0.374, p = 0.000), pancreatic parenchyma thickness (r = 0.549, p = 0.000), the density of the pancreas in the native phase of the scan (r = 0.568, p = 0.000), the values relative parenchyma enhancement ratio (r = 0.63, p = 0.000), pancreas stump volume (r = 0.508, p = 0.000) positively correlated with clinically significant pancreatic fistula and the number of acinar cells. Pancreatic duct diameter (r = −0.339, p = 0.001) negatively correlated with clinically significant pancreatic fistula and the number of acinar cells. Pancreatic fistula risk is 3.09 times higher with the number of acini more than 72.5%, sensitivity 75%, specificity 75.71%. Pancreatic fistula risk is 1.8 times higher with the density of the pancreas in the native phase over 35.5 HU sensitivity 62%, specificity 65%. Pancreatic fistula risk is 2.76 times higher with values parenchyma accumulation coefficient more than 1, sensitivity 75%, specificity 73%.Conclusions. Contrast enhancement computed tomography allows evaluating acinar index in the preoperative period to pick out the high-risk patient group to development of pancreatic fistula.

The purpose of the work is to study the features of histomorphometric changes in the pancreas of rats under conditions of hyperosmolar dehydration.Material and methods. The experiment was conducted on 40 adult white malerats. The control series of animals was 10 rats, the experimental series was divided depending on the degree of dehydration into 3 groups of 10 rats each.Results. Under conditions of hyperosmolar dehydration, we found the following statistically significant changes. An increase in acinus area was observed with mild dehydration and amounted to 39.9%; pancreatic islets – with moderate and severe degrees of 51,6 % and 45.9 %. The area of exocrine pancreatocytes decreased with moderate and severe degrees by 29,6 % and 35,9 %, with an increase in the area of their nuclei by 46,2 % under conditions of severe dehydration.Conclusions. Changes in the parenchyma of the pancreas and microvasculature progress in direct proportion to the increase in the severity of dehydration.

Background Desert rodent, Gerbillus tarabuli, is a seed-eating animal and do not require drinking water. It depends upon metabolic water. Understanding the functional characteristics of ocular glands which produce a watery lacrimal fluid is of interest. In the present study, we described the macroscopic anatomy and microscopic structure of the paraorbital glands in tarabul’s gerbil. Results There are up to four distinct orbital glands: lacrimal (LG), Harderian (HG), Meibomian (MG), and conjunctival mucous glands. Each eye has three eyelids, the main upper and lower lids and a third lid hidden between them in the inner corner of the eye. The LG is bipartite, situated on the dorsolateral aspect of the eyeball. The HG is large and localized deep in the orbit. The MG is found in the dense connective tissue plate. Upon light microscopic examination, the LG is an acinar gland; its secretory cells have mucous and serous granular cytoplasm. The endpieces of HG consist of tubuloalveoli, with two cellular types: prismatic vacuolated cells and pyramidal basophilic cells. The MG acini are closely arranged one after another. Each acinus contains a basal layer of myoepithelial cells and a mass of rounded, vacuolated cells. The nictitating membrane is formed by a semilunar fold of conjunctiva, supported by a hyaline cartilage. Numerous goblet cell clusters are detected in the covering conjunctiva particularly in the bulbar conjunctiva. Mucin glycoproteins appear to be abundant in the precorneal tear film, probably acting against desiccation stress. Conclusions Based on the data from this study, it could be concluded that the orbital glands of gerbil are well-developed, similar to other mammals.

The salivary and coxal glands in unfed larvae of the fresh-water mite Limnesia maculata (Müller, 1776) (Acariformes, Limnesiidae) were studied using light and electron microscopy. Three pairs of the salivary and one pair of the coxal glands constitute the prosomal gland complex. The salivary glands pertain to simple alveolar glands consisting of the single acinus with prismatic cells arranged around the intra-alveolar lumen. Owing to their spatial distribution, the salivary glands may be termed as medial, ventral and lateral. While the ventral and lateral glands are arranged symmetrically, the medial glands are disposed one after another at the frontal wall of the synganglion (brain). The medial and the ventral glands possess mostly electron-dense secretory granules supposedly of protein nature. The lateral glands show variable organization mainly having electron-lucent vacuoles. No well pronounced rough endoplasmic reticulum and Golgi bodies were discernible in the salivary glands. The coxal glands are well developed and composed of (i) the main portion (the so-called labyrinth) including at least two tightly opposed loops and extending backward along the brain, and (ii) the very short anterior portion/end piece transforming anteriorly into the terminal sac/bladder. The cells of the main portion are provided with apical microvilli, whereas the basal infolding/basal labyrinth is lacking. The cells of the anterior portion do not show the apical microvilli and the basal infoldings. The terminal sac is lined by a cuticle and has an ectodermal origin. The ducts of the salivary glands come together at the dorsal aspect of the bladder, to which they open forming the common podocephalic duct anteriorly. The latter opens on each side into the subcheliceral space. The well-developed podocephalic system suggests its active role in the living processes such as feeding and ion-water balance.

The signaling events controlling proliferation, survival, and apoptosis during mammary epithelial acinar morphogenesis remain poorly characterized. By imaging single-cell ERK activity dynamics in MCF10A acini, we find that these fates depend on the average frequency of non-periodic ERK pulses. High pulse frequency is observed during initial acinus growth, correlating with rapid cell motility. Subsequent decrease in motility correlates with lower ERK pulse frequency and quiescence. Later, during lumen formation, coordinated ERK waves emerge across multiple cells of an acinus, correlating with high and low ERK pulse frequency in outer surviving and inner dying cells respectively. Optogenetic entrainment of ERK pulses causally connects high ERK pulse frequency with inner cell survival. Acini harboring the PIK3CA H1047R mutation, commonly observed in breast cancer, display increased ERK pulse frequency, inner cell survival and loss of lumen formation. Thus, fate decisions during acinar morphogenesis are fine-tuned by different spatio-temporal coordination modalities of ERK pulse frequency.

Background: The parotid gland in sheep ends freely in front of the masseter muscle, and paracondylary section of occipital bone and extends deep until pterygoid extends of sphenoid bone and hyoid bone. The structure of salivary glands in mammals has been thoroughly studied using histological and sialographic method. This study aimed to reveal the detailed anatomic features and race-specific differences of the canal system of the parotid glands in Akkaraman sheep by using the corrosion cast technique. Materials and methods: Thirteen sheep parotid glands from 7 Akkaraman sheep were used in this study. Parotid glands were removed from their places with ducts. Measurements were made with a calliper from back to front, top to bottom and inside to outside. After dissection of the parotid glands, their volumes were measured according to the ‘Archimedes principle’. Also, 13 sheep parotid glands were examined using the polyester resin method. Results: In the present study, our average metric results were: length of parotid duct was 10.92 ± 1.027 cm, length of parotid gland was 5.87 ± 1.04 cm, volume of parotid gland was 12.50 ± 2.48 cm3, thickness of parotid gland was 0.75 ± ± 0.36 cm and width of parotid gland was 4.07 ± 0.43 cm. The average weight of the parotid gland of Akkaraman sheep was identified as 25.3 g. Accessory parotid gland was not encountered in the current study. Conclusions: It was observed that polyester entered into the parotid duct and filled up until the acinus and made both acinus and secretory ducts well-examined in this study. It was also observed that the parotid gland consisted of lobes and lobules. The average number of lobes was 12. The number of lobules in a lobe varied between 3 and 16, each lobe consisted of an average of 9 lobules. It was found that each lobe has its own lobar duct. Copyright © 2022 Via Medica.

A pancreatic acinus is a functional unit of the exocrine pancreas producing digest enzymes. Its pathobiology is crucial to pancreatic diseases including pancreatitis and pancreatic cancer, which can initiate from pancreatic acini. However, research on pancreatic acini has been significantly hampered due to the difficulty of culturing normal acinar cells in vitro. In this study, an in vitro model of the normal acinus, named pancreatic acinus-on-chip (PAC), is developed using reprogrammed pancreatic cancer cells. The developed model is a microfluidic platform with an epithelial duct and acinar sac geometry microfabricated by a newly developed two-step controlled “viscous-fingering” technique. In this model, human pancreatic cancer cells, Panc-1, reprogrammed to revert to the normal state upon induction of PTF1a gene expression, are cultured. Bioinformatic analyses suggest that, upon induced PTF1a expression, Panc-1 cells transition into a more normal and differentiated acinar phenotype. The microanatomy and exocrine functions of the model are characterized to confirm the normal acinus phenotypes. The developed model provides a new and reliable testbed to study the initiation and progression of pancreatic cancers.

BACKGROUND: Acute pancreatitis (AP) is a widespread disease resulting from the inflammation of acinar cells in the pancreas. β-hydroxybutyrate (BHB) is a water-soluble main ketone body synthesized in the human liver. The purpose of this study was to examine the possible therapeutic effects of BHB in the experimentally-induced AP model in rats. METHODS: In our study, male rats were randomly allotted into 6 groups, as control (0.9% saline i.p.), BHB1 (200 mg/kg BHB i.p.), BHB2 (2 doses of 200 mg/kg BHB i.p.), AP (4 doses of 50 µg/kg cerulein i.p., 4 doses at 1 h intervals), AP+BHB1 and AP+BHB2 groups. In pancreatic tissue sections, immunohistochemistry staining and western blot analysis for the inflammasome complex (caspase-1, ASC, and NLRP3) and inflammation-associated proteins (TNF-α and NF-κB) and a histopathological examination were performed. The levels of lipase, amylase, interleukin (IL)-18 and IL-1β in serum were measured. RESULTS: Several pathological degenerations, including edema, inflammatory cell infiltration, acinus necrosis, and bleeding were observed in the AP group, while the histological architecture of the control and the sham BHB1 and BHB2 groups were regular. The AP-induced pathological changes were considerably alleviated in the AP+BHB1 and AP+BHB2 groups. In the AP group, a conspicuous increase in caspase-1, ASC, NLRP3, TNF-α, and NF-κB proteins, and in the levels of amylase, lipase, IL-18, and IL-1β were detected. BHB treatments after AP induction decreased those proteins to the level of control. CONCLUSIONS: We demonstrated that BHB has the potential to cure AP by suppressing the NLRP3 inflammasome and can be used in the treatment of many diseases which progress through the NLRP3 inflammasome.

Understanding of airflow dynamics in the human pulmonary acinus is important for increasing targeted drug effectiveness and determining the health impact of toxic aerosols. However, there is a lack of quantitative data about the pulmonary airflow in realistic and flexible idealized geometries. This paper aims to numerically analyse the flow field of the pulmonary acinus using the computational fluid dynamics (CFD) model during transient breathing. Three-dimensional models with rhythmically expanding-contracting alveolar walls were developed for representing the pulmonary region of the human lung. Three different breathing scenarios were applied in the CFD simulations. The results showed that the transient flow conditions determined the transitions between flow types. The recirculating flow in the alveoli was observed for all cases and it was determined that its intensity depended on the breathing scenario. The flow velocity in the alveoli was slower than that of the channel flow. As we moved deeper into the lung, the flow pattern inside the alveoli exhibited a radial velocity profile. It was found that the alveolar flow exhibited a typical stenotic channel flow characteristics. As a result, the acinus models used in this study takes into account the alveolar wall motion based on physiological breathing conditions. To simulate or estimate the airflow dynamics, thus, the results obtained in this study can be easily utilized in the human lung airway models.

Acinar region consists of ~ 33 million airways and provides low resistance against the gas exchange with blood. A three-dimensional anatomically accurate model of pulmonary acinus is useful for simulation of fluid distribution, gas exchange, particle deposition, drug delivery, and detection of structural abnormalities in the lungs. In this study, the stochastic parametric Lindenmayer system has been used to generate the respiratory airways filling a given space. This model takes into account the mechanical properties and details of human acinus which can accurately predict the gas distribution throughout the lungs for the first time. The procedure of finding the dimensions and orientations of airways depends on several decision variables which have been found by particle swarm optimization algorithm. A novel procedure to generate the distribution of alveoli over airways has also been proposed. The morphometric characteristics (i.e., length, diameter, and orientation of airways) of the generated structure are successfully validated with their measured counterparts published in the literature. To examine the degree of asymmetry in the developed structure, it has been used for the prediction of the inert gas washout curve (i.e., the curve of exhaled concentration of inert gas against exhaled volume). This is due to the fact that the slope at the end part of this curve (i.e., alveolar slope) and its progression through the breaths is highly function of the asymmetric pattern of the human bronchial tree. The comparison of predicted slopes with experimental data indicates that the proposed method outperforms the previously reported models. For instance, the relative error of previous models in the prediction of the first slope is ~ 87%, whereas this study gives accurate results.

SummaryNeuronal health depends on quality control functions of autophagy, but mechanisms regulating neuronal autophagy are poorly understood. Previously, we showed that in Drosophila starvation-independent quality control autophagy is regulated by Acinus and the Cdk5-dependent phosphorylation of its serine437 (Nandi et al., 2017). Here, we identify the phosphatase that counterbalances this activity and provides for the dynamic nature of Acinus-S437 phosphorylation. A genetic screen identified six phosphatases that genetically interacted with an Acinus gain-of-function model. Among these, loss of function of only one, the PPM-type phosphatase Nil (CG6036), enhanced pS437-Acinus levels. Cdk5-dependent phosphorylation of Acinus serine437 in nil1 animals elevates neuronal autophagy and reduces the accumulation of polyQ proteins in a Drosophila Huntington’s disease model. Consistent with previous findings that Cd2+ inhibits PPM-type phosphatases, Cd2+-exposure elevated Acinus-serine437 phosphorylation which was necessary for increased neuronal autophagy and protection against Cd2+-induced cytotoxicity. Together, our data establish the Acinus- S437 phospho-switch as critical integrator of multiple stress signals regulating neuronal autophagy.

Salivary fluid secretion involves an intricate choreography of membrane transporters to result in the trans-epithelial movement of NaCl and water into the acinus lumen. Current models are largely based on experimental observations in enzymatically isolated cells where the Ca2+ signal invariably propagates globally and thus appears ideally suited to activate spatially separated Cl and K channels, present on the apical and basolateral plasma membrane, respectively. We monitored Ca2+ signals and salivary secretion in live mice expressing GCamp6F, following stimulation of the nerves innervating the submandibular gland. Consistent with in vitro studies, Ca2+ signals were initiated in the apical endoplasmic reticulum. In marked contrast to in vitro data, highly localized trains of Ca2+ transients that failed to fully propagate from the apical region were observed. Following stimuli optimum for secretion, large apical-basal gradients were elicited. A new mathematical model, incorporating these data was constructed to probe how salivary secretion can be optimally stimulated by apical Ca2+ signals.

Caspase is best known as an enzyme involved in programmed cell death, which is conserved among multicellular organisms. In addition to its role in cell death, caspase is emerging as an indispensable enzyme in a wide range of cellular functions, which have recently been termed caspase-dependent nonlethal cellular processes (CDPs). In this study, we examined the involvement of cell death signaling in tissue-size determination using Drosophila wing as a model. We found that the Drosophila executioner caspases Dcp-1 and Decay, but not Drice, promoted wing growth independently of apoptosis. Most of the reports on CDPs argue the importance of the spatiotemporal regulation of the initiator caspase, Dronc; however, this sublethal caspase function was independent of Dronc, suggesting a more diverse array of CDP regulatory mechanisms. Tagging of TurboID, an improved promiscuous biotin ligase that biotinylates neighboring proteins, to the C terminus of caspases revealed the differences among the neighbors of executioner caspases. Furthermore, we found that the cleavage of Acinus, a substrate of the executioner caspase, was important in promoting wing growth. These results demonstrate the importance of executioner caspase-mediated basal proteolytic cleavage of substrates in sustaining tissue growth. Given the existence of caspase-like DEVDase activity in a unicellular alga, our results likely highlight the original function of caspase—not cell death, but basal proteolytic cleavages for cell vigor.

Apoptotic chromatin condensation inducer in the nucleus (Acinus) is an RNA-binding protein that has a functional role in inducing apoptotic chromatin condensation and regulating messenger RNA (mRNA) processing. Acinus interacts with the spliceosomal machinery and is a member of the ASAP (apoptosis and splicing-associated protein complex) as well as the EJC (exon junction complex), which gets deposited onto mRNA during splicing. In this study, we have used in vivo splicing assays to characterize the function of Acinus in pre-mRNA splicing more closely. We show that full-length Acinus-S', an isoform of Acinus, does not have a role in modulating splice site selection in human immunodeficiency virus 1 minigene reporter system. In contrast, we observed that the tethering of arginine/serine (RS) and RNPS1-SAP18-binding (RSB) domains of Acinus could regulate the selection of alternative splice sites, thereby revealing the potential of Acinus in stimulating alternative splicing. Altogether, our data suggest that the RS and RSB domains play a critical role in regulating splicing activity via selection of distinct splice sites during pre-mRNA splicing.

Purpose: To describe and quantify findings of intraductal obstruction during probing expressible and nonexpressible meibomian glands (MGs) in patients with obstructive meibomian gland dysfunction using a 1-mm intraductal MG probe. Methods: A retrospective study of probe findings from 108 consecutive patients. Nonparametric tests using SPSS software 25.0 to explore relationships between expressibility and probe findings. Results: Of 11,776 probed glands of 404 lids, 84% showed mechanical resistance (MR) and 16% showed no resistance (NR). Fixed, firm, focal unyielding resistance (FFFUR) occurred in 79.5% of obstructed glands, and nonfixed, nonfocal easily yielding soft resistance (SFT) in 20.4%. FFFUR was characterized by an audible and tactile “firm pop” (FP) or “firm gritty” (FG) sensation. No significant difference in MR and FFFUR for lids between 0% and >90% gland expressibility was observed. FP correlated with increased expressibility (P = 0.011), lid tenderness (P = 0.045), and complete proximal obstruction (P = 0.037), whereas SFT correlated with reduced expressibility (P = 0.016). Upper lids showed greater incidence of MR (P < 0.001), FFFUR (P < 0.001), and FG (P < 0.001), whereas lower lids showed greater expressibility (P < 0.001) and NR (P < 0.001). Conclusions: FFFUR was the most common probe finding in a large series of consecutively probed MGs, with an incidence of 67% of glands and 80% of obstructed glands. FFFUR was independent of gland expressibility, demonstrating expressible glands harbor FFFUR deep to at least one acinus. FP was associated with expressible gland occult obstruction and lid tenderness. SFT correlated with reduced expressibility, perhaps related to altered duct/duct contents. Upper lids correlated with increased MR, FFFUR, and FG and lower lids with increased expressibility and NR, possibly reflecting contrasting anatomy and blink-related microtrauma.