Histological Analysis Of Tissues Research Articles

Combined bacterial translocation and cholestasis aggravates liver injury by activation pyroptosis in obstructive jaundice

This study explores the mechanism by which obstructive jaundice (OJ) induces liver damage through pyroptosis. We induced OJ in rats via bile duct ligation and assessed liver damage using serum biochemical markers and histological analysis of liver tissue. Pyroptosis was investigated through immunofluorescence, ELISA, Western blot, and quantitative RT-PCR techniques. Additionally, we examined intestinal function and fecal microbiota alterations in the rats using 16S rDNA sequencing. In vitro experiments involved co-culturing Kupffer cells and hepatocytes, which were then exposed to bile and lipopolysaccharide (LPS). Our findings indicated that OJ modified the gut microbiota, increasing LPS levels, which, in conjunction with bile, initiated a cycle of inflammation, fibrosis, and cell death in the liver. Mechanistically, OJ elevated necrotic markers such as ATP, which in turn activated pyroptotic pathways. Increased levels of pyroptosis-related molecules, including NLRP3, caspase-1, gasdermin D, and IL-18, were confirmed. In our co-cultured cell model, bile exposure resulted in cell death and ATP release, leading to the activation of the NLRP3 inflammasome and its downstream effectors, caspase-1 and IL-18. The combination of bile and LPS significantly intensified pyroptotic responses. This study is the first to demonstrate that LPS and bile synergistically exacerbate liver injury by promoting necrosis and pyroptosis, unveiling a novel mechanism of OJ-associated hepatic damage and suggesting avenues for potential preventive or therapeutic interventions.

Commentary to histologic analysis of gonadal tissue in patients with turner syndrome and Y chromosome material

Commentary to histologic analysis of gonadal tissue in patients with turner syndrome and Y chromosome material

Helicobacter pylori infection exacerbates metabolic dysfunction-associated steatotic liver disease through lipid metabolic pathways: a transcriptomic study

BackgroundThe relationship between Helicobacter pylori (H. pylori) infection and metabolic dysfunction-associated steatotic liver disease (MASLD) has attracted increased clinical attention. However, most of those current studies involve cross-sectional studies and meta-analyses, and experimental mechanistic exploration still needs to be improved. This study aimed to investigate the mechanisms by which H. pylori impacts MASLD.MethodsWe established two H. pylori-infected (Cag A positive and Cag A negative) mouse models with 16 weeks of chow diet (CD) or high-fat diet (HFD) feeding. Body weight, liver triglyceride, blood glucose, serum biochemical parameters, inflammatory factors, and insulin resistance were measured, and histological analysis of liver tissues was performed. Mouse livers were subjected to transcriptome RNA sequencing analysis.ResultsAlthough H. pylori infection could not significantly affect serum inflammatory factor levels and serum biochemical parameters in mice, serum insulin and homeostatic model assessment for insulin resistance levels increased in CD mode. In contrast, H. pylori Cag A + infection significantly aggravated hepatic pathological steatosis induced by HFD and elevated serum inflammatory factors and lipid metabolism parameters. Hepatic transcriptomic analysis in the CD groups revealed 767 differentially expressed genes (DEGs) in the H. pylori Cag A + infected group and 1473 DEGs in the H. pylori Cag A- infected group, and the “nonalcoholic fatty liver disease” pathway was significantly enriched in KEGG analysis. There were 578 DEGs in H. pylori Cag A + infection combined with the HFD feeding group and 820 DEGs in the H. pylori Cag A- infected group. DEGs in the HFD groups were significantly enriched in “fatty acid degradation” and “PPAR pathway.” Exploring the effect of different Cag A statuses on mouse liver revealed that fatty acid binding protein 5 was differentially expressed in Cag A- H. pylori. DEG enrichment pathways were concentrated in the “PPAR pathway” and “fatty acid degradation.”ConclusionsClinicians are expected to comprehend the impact of H. pylori on MASLD and better understand and manage MASLD. H. pylori infection may exacerbate the development of MASLD by regulating hepatic lipid metabolism, and the H. pylori virulence factor Cag A plays a vital role in this regulation.

Resposta reprodutiva de Bulimulus tenuissimus (Mollusca) como hospedeiro intermediário de Angiostrongylus cantonensis (Nematoda)

The snail Bulimulus tenuissimus is a terrestrial gastropod widely distributed in the Americas, Asia, Africa and some countries of other continents. It typically occurs in the same areas as Angiostrongylus cantonensis, which needs a mollusk as intermediate host. In spite of this, the literature is scant about the relationship of these organisms. Specimens of B. tenuissimus were experimentally infected with L1 larvae of A. cantonensis. Weekly, until the third week post exposure, the reproductive parameters were analyzed and snails were dissected for collection of hemolymph, along with the albumen gland and tissues for histological analysis. The total number of eggs laid, total number of newly hatched snails and number of newly hatched snails/eggs laid were higher in the infected snails, but the differences observed were not significant. The galactogen content in the albumen gland was significantly reduced from the second week post exposure onward. Also, in spite of presence of larvae in the gonadal region of the snail with granuloma-like structures and some histological changes, gametogenesis occurred regularly in the infected hosts. The results are worrisome, since they showed that B. tenuissimus is an intermediate host to A. cantonensis which supports infection without changes in its reproductive biology and activity. The present study sheds more light on a snail that is a newly recorded experimental and natural intermediate host of A. cantonensis, which is widely distributed and occurs in areas were neural angiostrongyliasis has been recorded. Therefore, this snail can act in the nature as an important agent for dispersion of neural angiostrongyliasis, posing a serious problem to human and animal public health.

Dynamics of Inflammatory and Pathological Changes Induced by Single Exposure of Particulate Matter (PM2.5) in Mice: Potential Implications in COPD.

Chronic Obstructive Pulmonary Disease (COPD) is a progressive disorder of lungs marked by chronic bronchitis and emphysema. Particulate matter (PM2.5), a major component of air pollution has been correlated with COPD incidence. The present work aimed to understand dynamics of cellular/molecular players behind PM2.5-mediated COPD pathogenesis in mice by conducting dose and time-course studies. Single intratracheal exposure of PM2.5 at a dose of either 100 or 200 μg induced inflammatory response in lungs at 4 days. Time course studies showed that inflammation once triggered by PM2.5 is progressive in nature as reflected by data on BALF inflammatory cells at 7/14 days. Similarly, various cytokines/chemokines (KC/IL-6/TNF-α/IL-1β/G-CSF/MCP-1) peak at either 7 or 14 days. However, inflammation declined sharply at 21 days. Data on LPO/GSH and activities of SOD/Catalase show induction of continuous oxidative stress in lung tissue. Next, enhanced mtROS in the CD11b+ inflammatory cells confirms the redox imbalance in neutrophils/macrophages. A continuous decline in lung function was observed till 28 days. Further, histological analysis of lung tissues at 28 days confirmed the presence of emphysematous lesions, validating the potency of PM2.5 to cause irreversible damage to lungs through complex interplay of various cellular/molecular players which may be exploited as potential preventive/therapeutic targets.

Hepatoprotective Effects of Aqueous Extract of Perilla fructescens against Alcohol-Induced Liver Injury in Mice

Excessive alcohol intake leads to significant physiological complications, particularly alcoholic liver diseases (ALD). The extent of liver damage caused by ethanol correlates with increased oxidative stress and accumulation of lipids in the hepatic tissue. In this study, we investigated the defense properties of the aqueous extract of Perilla frutescens Briton Var. acuta Kudo (PF) on hepatic injury in chronically ethanol-treated mice. The mice were orally administered the water extract from PF for 4 weeks with ethanol treatment (3 g/kg. P.O.). The level of malondialdehyde (MDA) in the liver tissues was determined. A substantial increase in MDA generation was detected in the livers of mice subjected to ethanol exposure, whereas the administration of PF markedly reduced MDA levels in hepatic tissues. Additionally, histological analysis of the liver tissue was performed. Histopathological investigation revealed a significant reduction in hepatocellular necrosis in the PF-treated group. This study demonstrated that the aqueous extract of Perilla frutescens Briton Var. acuta Kudo (PF) attenuated chronic ethanol-induced liver injury by augmenting the antioxidant capacity of mice. These results can be utilized for the development of high-value-added products using PF.

Histologic analysis of gonadal tissue in patients with Turner syndrome and Y chromosome material

This study investigates gonadal histology in individuals with Turner syndrome assigned female at birth and Y-chromosome material (TS+Y) who underwent prophylactic gonadectomy. Despite case reports suggesting spontaneous menarche and pregnancies in TS+Y, this research reveals the absence of germ cells, indicating low fertility likelihood. Germ cell neoplasia in-situ was present in some patients, emphasizing a non-negligible risk of cancer precursor. As no malignancies were found even in older individuals, the study challenges the immediate need for prophylactic gonadectomy upon TS+Y diagnosis. Limited fertility benefits are suggested, emphasizing the need for further research on optimal timing and criteria for the procedure.

Potential Therapeutic Implications of Securidaca longipedunculata Root Bark Ethanolic Extract in a Rat Model of Traumatic Brain Injury

This study explores the neuroprotective potential of Securidaca longipedunculata (Violet tree) used in traditional African medicine for treating traumatic brain injury (TBI). Fifteen albino rats were divided into three groups: a control group without TBI or treatment, a TBI group treated with S. longipedunculata (400 mg/kg body weight for 21 days), and a TBI group without treatment. TBI was induced using the weight drop method. Neurological responses were assessed using a revised neurological severity score, and haematological parameters (WBC, RBC, HB, PCV, neutrophils, lymphocytes, and monocytes) were measured, including the neutrophil to lymphocyte ratio. Plasma glucose levels were monitored hourly for three hours post-TBI and daily for three days. Histological analysis of brain tissues was performed. Results indicated that rats treated with S. longipedunculata exhibited significantly lower neurological severity scores and better responsiveness compared to untreated TBI rats during the first two weeks of treatment. Treated rats also showed higher PCV, HB, and RBC levels, and lower WBC, neutrophil, and lymphocyte counts. Plasma glucose levels in treated rats steadily decreased, a trend not seen in untreated TBI rats. Histology revealed less severe brain lesions in treated rats. The study concludes that S. longipedunculata may reduce inflammatory responses and enhance hematopoietic activity in TBI rats, suggesting its potential for developing new neuroprotective pharmaceuticals.

Combining poly-epitope MoonTags and labeled nanobodies for signal amplification in cell-specific PET imaging in vivo

Immunorecognition provides an excellent basis for targeted imaging techniques covering a wide range from basic research to diagnostics and from single cells to whole organisms. Fluorescence- or radioisotope-labeled antibodies, antibody fragments or nanobodies enable a direct signal readout upon binding and allow for versatile imaging from microscopy to whole-body imaging. However, as the signal intensity directly correlates with the number of labeled antibodies bound to their epitopes (1:1 binding), sensitivity for low-expressing epitopes can be limiting for visualization. For the first time, we developed poly-epitope tags with multiple copies (1 to 7) of a short peptide epitope, specifically the MoonTag, that are recognized by a labeled nanobody and aimed at signal amplification in microscopy and cell-specific PET imaging. In transiently transfected HeLa cells or stably transduced A4573 cells we characterized complex formation and in vitro signal amplification. Indeed, using fluorescently and radioactively labeled nanobodies we found an approximately linear signal amplification with increasing numbers of epitope copies in vitro. To test the poly-epitope approach in vivo, A4573 tumor cells were injected subcutaneously into the shoulder of NSG mice, with A4573 tumor cells expressing a poly-epitope of 7 MoonTags on one side and WT cells on the other side. Using a [68Ga]-labeled NODAGA-conjugated MoonTag nanobody, we performed PET/CT imaging at day 8–9 after tumor implantation. Specific binding of a [68Ga]-labeled NODAGA-conjugated MoonTag nanobody was observed in 7xMoonTag tumors (1.7 ± 0.5%ID/mL) by PET imaging, showing significantly higher radiotracer accumulation compared to the WT tumors (1.1 ± 0.3%ID/mL; p < 0.01). Ex vivo gamma counter measurements confirmed significantly higher uptake in 7xMoonTag tumors compared to WT tumors (p < 0.001). In addition, MoonTag nanobody binding was detected by autoradiography which was spatially matched with histological analysis of the tumor tissues. In conclusion, we expect nanobody-based poly-epitope tag strategies to be widely applicable for multimodal imaging techniques given the advantageous properties of nanobodies and their amenability to genetic and chemical engineering.

The ric-8b protein (resistance to inhibitors of cholinesterase 8b) is key to preserving contractile function in the adult heart

Resistance to inhibitors of cholinesterases (ric-8 proteins) are involved in modulating G-protein function, but little is known of their potential physiological importance in the heart. In the present study, we assessed the role of resistance to inhibitors of cholinesterase 8b (Ric-8b) in determining cardiac contractile function. We developed a murine model in which it was possible to conditionally delete ric-8b in cardiac tissue in the adult animal after the addition of tamoxifen. Deletion of ric-8b led to severely reduced contractility as measured using echocardiography days after administration of tamoxifen. Histological analysis of the ventricular tissue showed highly variable myocyte size, prominent fibrosis, and an increase in cellular apoptosis. RNA sequencing revealed transcriptional remodeling in response to cardiac ric-8b deletion involving the extracellular matrix and inflammation. Phosphoproteomic analysis revealed substantial downregulation of phosphopeptides related to myosin light chain 2. At the cellular level, the deletion of ric-8b led to loss of activation of the L-type calcium channel through the β-adrenergic pathways. Using fluorescence resonance energy transfer-based assays, we showed ric-8b protein selectively interacts with the stimulatory G-protein, Gαs. We explored if deletion of Gnas (the gene encoding Gαs) in cardiac tissue using a similar approach in the mouse led to an equivalent phenotype. The conditional deletion of the Gαs gene in the ventricle led to comparable effects on contractile function and cardiac histology. We conclude that ric-8b is essential to preserve cardiac contractile function likely through an interaction with the stimulatory G-protein and downstream phosphorylation of myosin light chain2.

Organic light-emitting diode therapy promotes longevity through the upregulation of SIRT1 in senescence-accelerated mouse prone 8 mice

Phototherapy has been extensively used to prevent and treat signs of aging and stimulate wound healing, and phototherapy through light-emitting diodes (LEDs). In contrast to LED, organic LED (OLED) devices are composed of organic semiconductors that possess novel characteristics. We investigated the regenerative potential of OLED for restoring cellular potential from senescence and thus delaying animal aging. Bone marrow–derived stem cells (BMSCs) and adipose-derived stem cells (ADSCs) were isolated from the control and OLED- treated groups to evaluate their proliferation, migration, and differentiation potentials. Cellular senescence was evaluated using a senescence-associated β-galactosidase (SA-β-gal) activity assay and gene expression biomarker assessment. OLED treatment significantly increased the cell proliferation, colony formation, and migration abilities of stem cells. SA-β-gal activity was significantly decreased in both ADSCs and BMSCs in the OLED-treated group. Gene expression biomarkers from treated mice indicated a significant upregulation of IGF-1 (insulin growthfactor-1). The upregulation of the SIRT1 gene inhibited the p16 and p19 genes then to downregulate the p53 expressions for regeneration of stem cells in the OLED-treated group. Our findings indicated that the survival rates of 10-month aging senescence-accelerated mouse prone 8 mice were prolonged and that their gross appearance improved markedly after OLED treatment. Histological analysis of skin and brain tissue also indicated significantly greater collagen fibers density, which prevents ocular abnormalities and β-amyloid accumulation. Lordokyphosis and bone characteristics were observed to resemble those of younger mice after OLED treatment.In conclusion, OLED therapy reduced the signs of aging and enhanced stem-cell senescence recovery and then could be used for tissue regeneration.

Malic enzyme 1 knockout has no deleterious phenotype and is favored in the male germline under standard laboratory conditions.

Malic Enzyme 1 (ME1) plays an integral role in fatty acid synthesis and cellular energetics through its production of NADPH and pyruvate. As such, it has been identified as a gene of interest in obesity, type 2 diabetes, and an array of epithelial cancers, with most work being performed in vitro. The current standard model for ME1 loss in vivo is the spontaneous Mod-1 null allele, which produces a canonically inactive form of ME1. Herein, we describe two new genetically engineered mouse models exhibiting ME1 loss at dynamic timepoints. Using murine embryonic stem cells and Flp/FRT and Cre/loxP class switch recombination, we established a germline Me1 knockout model (Me1 KO) and an inducible conditional knockout model (Me1 cKO), activated upon tamoxifen treatment in adulthood. Collectively, neither the Me1 KO nor Me1 cKO models exhibited deleterious phenotype under standard laboratory conditions. Knockout of ME1 was validated by immunohistochemistry and genotype confirmed by PCR. Transmission patterns favor Me1 loss in Me1 KO mice when maternally transmitted to male progeny. Hematological examination of these models through complete blood count and serum chemistry panels revealed no discrepancy with their wild-type counterparts. Orthotopic pancreatic tumors in Me1 cKO mice grow similarly to Me1 expressing mice. Similarly, no behavioral phenotype was observed in Me1 cKO mice when aged for 52 weeks. Histological analysis of several tissues revealed no pathological phenotype. These models provide a more modern approach to ME1 knockout in vivo while opening the door for further study into the role of ME1 loss under more biologically relevant, stressful conditions.

Primary disease of adipose tissue: When to think about and how to evaluate it in clinical practice?

Primary diseases of adipose tissue are rare disorders resulting from impairments in the physiological functions of adipose tissue (lipid stockage and endocrine function). It mainly refers to lipodystrophy syndromes with subcutaneous adipose tissue atrophy and/or altered body distribution of adipose tissue leading to insulin resistance, diabetes, hepatic steatosis, dyslipidemia, cardiovascular complications and polycystic ovary syndrome in women. Those syndromes are congenital or acquired, and lipoatrophy is partial or generalized. The diagnosis of lipodystrophy syndromes is often unrecognized, delayed and/or inaccurate, while it is of major importance to adapt investigations to search for specific comorbidities, in particular cardiovascular involvement, and set up multidisciplinary care, and in some cases specific treatment. Physicians have to recognize the clinical and biological elements allowing to establish the diagnosis. Lipodystrophic syndromes should be considered, notably, in patients with diabetes at a young age, with a normal or low BMI, negative pancreatic autoantibodies, presenting clinical signs of lipodystrophy and insulin resistance (acanthosis nigricans, hyperandrogenism, hepatic steatosis, high insulin doses). The association of diabetes and a family history of severe and/or early cardiovascular disease (coronary atherosclerosis, cardiomyopathy with rhythm and/or conduction disorders) may reveal Dunnigan syndrome, the most frequent form of familial lipodystrophy, due to LMNA pathogenic variants. Clinical assessment is primarily done through clinical examination: acanthosis nigricans, abnormal adipose tissue distribution, lipoatrophy, muscular hypertrophy, acromegaloid or Cushingoid features, lipomas, highly visible subcutaneous veins, may be revealing signs. The amount of circulating adipokines may reflect of adipose dysfunction with low leptinemia and adiponectinemia. Other biological metabolic parameters (hypertriglyceridemia, hyperinsulinemia, increased glycemia and hepatic enzymes) may also represent markers of insulin resistance. Quantification of total body fat by impedancemetry or dual-photon X-ray absorptiometry (DEXA) reveals decreased total body mass, in correlation with adipose tissue atrophy; metabolic magnetic resonance imaging can also quantify intraperitoneal and abdominal fat and the degree of hepatic steatosis. Histological analysis of adipose tissue showing structural abnormalities should be reserved for clinical research. Acquired lipodystrophic syndromes most often lead to similar clinical phenotype as congenital syndromes with generalized or partial lipoatrophy. The most frequent causes are old anti-HIV therapy or glucocorticoid treatments. Family history, history of treatments and clinical examination, including a careful physical examination, are keys for diagnosis.

Morphological and molecular preservation through universal preparation of fresh-frozen tissue samples for multimodal imaging workflows.

The landscape of tissue-based imaging modalities is constantly and rapidly evolving. While formalin-fixed, paraffin-embedded material is still useful for histological imaging, the fixation process irreversibly changes the molecular composition of the sample. Therefore, many imaging approaches require fresh-frozen material to get meaningful results. This is particularly true for molecular imaging techniques such as mass spectrometry imaging, which are widely used to probe the spatial arrangement of the tissue metabolome. As high-quality fresh-frozen tissues are limited in their availability, any sample preparation workflow they are subjected to needs to ensure morphological and molecular preservation of the tissues and be compatible with as many of the established and emerging imaging techniques as possible to obtain the maximum possible insights from the tissues. Here we describe a universal sample preparation workflow, from the initial step of freezing the tissues to the cold embedding in a new hydroxypropyl methylcellulose/polyvinylpyrrolidone-enriched hydrogel and the generation of thin tissue sections for analysis. Moreover, we highlight the optimized storage conditions that limit molecular and morphological degradation of the sections. The protocol is compatible with human and plant tissues and can be easily adapted for the preparation of alternative sample formats (e.g., three-dimensional cell cultures). The integrated workflow is universally compatible with histological tissue analysis, mass spectrometry imaging and imaging mass cytometry, as well as spatial proteomic, genomic and transcriptomic tissue analysis. The protocol can be completed within 4 h and requires minimal prior experience in the preparation of tissue samples for multimodal imaging experiments.

Evidence of mutant huntingtin and tau-related pathology within neuronal grafts in Huntington’s disease cases

A number of post-mortem studies conducted in transplanted Huntington’s disease (HD) patients from various trials have reported the presence of pathological and misfolded proteins, in particular mutant huntingtin (mHtt) and phosphorylated tau neuropil threads, in the healthy grafted tissue. Here, we extended these observations with histological analysis of post-mortem tissue from three additional HD patients who had received similar striatal allografts from the fetal tissue transplantation trial conducted in Los Angeles in 1998. Immunohistochemical staining was performed using anti-mHtt antibodies, EM48 and MW7, as well as anti-hyperphosphorylated tau antibodies, AT8 and CP13. Immunofluorescence was used to assess the colocalization of EM48+ mHtt aggregates with the neuronal marker MAP2 and/or the extracellular matrix protein phosphacan in both the host and grafts. We confirmed the presence of mHtt aggregates within grafts of all three cases as well as tau neuropil threads in the grafts of two of the three transplanted HD patients. Phosphorylated tau was also variably expressed in the host cerebral cortex of all three subjects. While mHtt inclusions were present within neurons (immunofluorescence co-localization of MAP2 and EM48) as well as within the extracellular matrix of the host (immunofluorescence co-localization of phosphacan and EM48), their localization was limited to the extracellular matrix in the grafted tissue. This study corroborates previous findings that both mHtt and tau pathology can be found in the host and grafts of HD patients years post-grafting.

#539 The active ingredient in the Nuphar lutea plant DTBN, ameliorates kidney damage and inflammation in a mouse model of chronic kidney disease (CKD)

Abstract Background and Aims Complications associated with Chronic Kidney Disease (CKD), such as disease progression and anemia, are closely linked to heightened inflammation mediated by the innate immune response. This inflammation can be mitigated through the use of anti-inflammatory agents. 6,6′-dihydroxythiobinupharidine (DTBN), an active compound derived from the aquatic plant Nuphar lutea, demonstrates notable anti-inflammatory properties, primarily by inhibiting NF-κB and LPS-induced cytokine activation. DTBN has shown efficacy in priming neutrophils, enhancing phagocytosis, regulating reactive oxygen species (ROS) production, and modulating NET formation. This study aimed to assess the impact of DTBN on CKD in mice. Method Male C57BL/6J mice, aged 8 weeks, were subjected to an adenine diet known to induce CKD through crystal deposition and tubulointerstitial inflammation. Both control and CKD-induced mice received intraperitoneal injections of DTBN (25 μg QOD) or saline and were euthanized after 8 weeks for evaluation. Results CKD mice treated with DTBN exhibited a significant decrease in serum urea and creatinine levels compared to untreated CKD mice (reduction by 1.4-fold and 1.3-fold, respectively). Histological analysis of kidney tissues revealed a notable reduction in F4/80 positive macrophage infiltration (3.4-fold decrease) and damaged renal areas (three-fold decrease), along with diminished kidney TGF-β levels in DTBN-treated CKD mice. Moreover, the p65 subunit of NF-κB showed a three-fold reduction in CKD mice treated with DTBN compared to untreated CKD mice. Indices of kidney inflammation (IL-1β, IL-6, and P-STAT3) were notably decreased in CKD mice treated with DTBN (reduction by 1.4-fold, 1.6-fold, and 2.9-fold, respectively) compared to untreated CKD mice. Notably, DTBN treatment in control mice did not induce apparent tissue damage; however, it led to reduced weight gain and mild hypoalbuminemia without proteinuria. Conclusion DTBN demonstrated significant improvements in renal function and inflammation indices in CKD mice. Hence, DTBN and substances similar to DTBN could be considered as supplementary treatments for CKD patients.

Histological analysis of laser-enabled tissue coring with a novel 2910 nm erbium-doped fluoride glass fiber laser.

There remains an unmet need for a laser-enabled tissue coring device that can effectively improve face and neck skin laxity and rhytides. We investigate a novel 2910 nm erbium-doped fluoride glass fiber laser (2910 nm fiber laser) (UltraClear; Acclaro Medical) for laser-coring of submental tissue. Five subjects, Glogau scale III-IV, were treated with a single pulse of the laser-coring mode of the 2910 nm fiber laser in the submentum. A 4 mm punch biopsy was immediately performed. Biopsy specimens were sectioned and stained with hematoxylin and eosin and placed on glass slides. All sections were reviewed, and sections containing the center of the transected core were analyzed for depth and diameter of the ablative microchannel and width of the surrounding zone of coagulation. A total of 15 intact micro-cores were analyzed. Histological analysis revealed an average ± standard deviation microchannel diameter of 242.5 ± 65.2 µm, an average ablative depth of 980 ± 318.8 µm, and an average zone of coagulation of 104 ± 32 µm. Laser-enabled tissue coring with a novel 2910 nm fiber laser can safely achieve a wider microchannel diameter with ablative depth extending to the mid and deep dermis, which has the potential for collagen contraction and tissue tightening. Laser-coring to this ablation diameter and depth and with the surrounding zone of coagulation was found to be safe without adverse effects of post-inflammatory erythema or scarring in our study.

PSIII-11 Impacts of late gestational in utero heat stress on small intestine dynamics of neonatal dairy calves

Abstract Late gestation heat stress in dairy cows has been shown to negatively affect offspring growth and development. In utero heat stressed calves have altered small intestine morphology and an impaired ability to absorb colostral immunoglobulin G (IgG). Thus, the objective of this study was to characterize potential cellular and molecular alterations in the small intestine of neonatal in utero heat stressed calves. In the last ~56 d of gestation pregnant dams were either heat stressed (shade; n = 41) or cooled (shade, fans, soakers; n = 41) resulting in heifers that were in utero heat stressed (IUHS, n = 15) or in utero cooled (IUCL, n = 15). Heifers were fed 3.78 L of high-quality colostrum within 2 h of birth. Apparent efficiency of absorption (AEA) of IgG was calculated by measuring IgG content fed in colostrum and in 24 h serum. Within 4.6 ± 2.3 h of birth a subset of calves (n = 8/treatment) not fed colostrum were euthanized to collect samples from the ileum. Tissue for histological analysis was placed in 10% neutral buffered formalin before being dehydrated, embedded in paraffin, cut into 5 μm thicknesses, and mounted to glass slides. The TUNEL method was used to identify apoptotic cells using the Keyence BZ-X800 Microscope. Tissue for gene expression analysis was snap-frozen and kept at -80°C before RNA extraction and cDNA synthesis. The transcript abundance of endosomal (FCGRT, DAB2, MAMDC4), tight junction (ZO1, ZO2, ZO3, OCLN, CLDN1), and heat shock (HSP90, HSF1) related genes were measured by qPCR using the CFX96 Real-Time PCR detection System (BIO-RAD). Data were analyzed using PROC MIXED or PROC GLIMMIX depending on the response variable. TUNEL results are expressed as the proportion of positive cells to total cells. Quantitative PCR data were analyzed by assessing the estimates of the model relative to the geometric mean of 3 reference genes (ACTB, GADPH, RSP9; ΔΔCT). The concentration of colostrum IgG fed to calves was not different (136.1 vs. 122.5 g/L; IUHS vs. IUCL, respectively; P = 0.32), but AEA of IgG was reduced in IUHS relative to IUCL calves (23.5 vs. 33.3%; P &amp;lt; 0.01). The proportion of apoptotic cells within the villi of the ileum was increased in IUHS calves compared with IUCL (2.11 vs. 1.57%; P &amp;lt; 0.01). Ileum gene transcript abundance of DAB2 and MAMDC4 were increased (P &amp;lt; 0.01), while FCGRT transcripts tended to increase in IUHS calves (P = 0.08). All tight junction and heat shock-related gene transcripts were increased within the ileum of IUHS calves (P ≤ 0.02) with the exceptions of CLDN1 and HSP90, which were not different between treatments (P ≥ 0.22).These results suggest that exposure to heat stress in utero impact small intestine integrity after birth and affect key IgG transporters, providing insight into underlying mechanisms responsible for reduced IgG absorption in IUHS calves.

Metabolic dysfunction in the myocardium three months after exertional heat stroke in mice

In humans, exposure to heat stroke has proven to be a risk factor for development of cardiovascular disease later in life. We hypothesized that exposure to exertional heat stroke (EHS) would result in the development of similar long-term cardiac disease in mice. In this study we followed mice for three months after EHS, using ultrasound imaging of the heart, metabolomics and histological analysis of ventricular tissue and biomarker analysis after 4 weeks of recovery. Methods: Mice were instrumented with temperature telemetry devices and were trained to run on forced running wheels using an incremental exercise protocol. EHS mice ran in an temperature elevated environmental chamber; females 37.5°C; males 34°C; whereas, matched exercise control mice (EXC) ran in 22-23°C. Running stopped when EHS mice reached symptom limitation (unconsciousness). The mice were followed for 12 wks post EHS, with two ultrasound measures at 2 and 10 wks of recovery. At the end of the study, mice were anesthetized, a blood sample drawn, and ventricular tissue collected for metabolomics. RESULTS: Male but not female EHS mice gained ~10% greater body mass compared to EXC over the course of recovery ( P&lt;0.01). Hearts from male but not female EHS mice exhibited elevations in heart mass per tibia length ( P&lt;0.01). At three months, metabolomics in male EHS hearts revealed significant elevations in glucose and glucose metabolites and significant decreases in acylcarnitines consistent with a metabolic shift toward glucose and away from lipid metabolism. In contrast, female hearts exhibited fewer abnormalities but with significant elevations in lipid and arachidonate metabolites. At two weeks post, there were no differences in male ultrasound measures between EHS and EXC mice but in females there was a reduced posterior wall velocity ( P=0.012) and a trend towards narrower posterior wall thickness ( P= 0.06) . Between 2 and 12 wks post EHS, there were significant elevations in fractional shortening in males ( P&lt;0.05) and elevations in posterior wall velocity ( P&lt;0.01). In contrast, females exhibited significant reductions posterior wall velocity. From blood samples, male EHS mice had increased HDL and females exhibited decreased HDL (p&lt;0.01 in both). LDL increased only in males P&lt;0.05. Vascular adhesion molecules sICAM ( P&lt;0.01) and Pecam1 ( P&lt;0.01) were significantly decreased in EHS males and females and e-Selectin was decreased in EHS males only ( P&lt;0.001). Total serum protein was significantly reduced in both male and females ( P&lt;0.01). Male EHS mice also exhibited significant elevations in white blood cell count and total lymphocytes ( P=0.01) suggesting ongoing activation of the immune system . CONCLUSIONS: In this controlled preclinical model of EHS, both male and female mice exhibited long-lasting cardiovascular and systemic disorders that could account for the lingering incidence of cardiovascular disease and poor overall health in heat stroke victims. Supported by US Army Med. Research and Devel. Command BA180078 and the BK and Betty Stevens Endowment. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Host response during unresolved urinary tract infection alters female mammary tissue homeostasis through collagen deposition and TIMP1.

Exposure to pathogens throughout a lifetime influences immunity and organ function. Here, we explore how the systemic host-response to bacterial urinary tract infection (UTI) induces tissue-specific alterations to the mammary gland. Utilizing a combination of histological tissue analysis, single cell transcriptomics, and flow cytometry, we identify that mammary tissue from UTI-bearing mice displays collagen deposition, enlarged ductal structures, ductal hyperplasia with atypical epithelial transcriptomes and altered immune composition. Bacterial cells are absent in the mammary tissue and blood of UTI-bearing mice, therefore, alterations to the distal mammary tissue are mediated by the systemic host response to local infection. Furthermore, broad spectrum antibiotic treatment resolves the infection and restores mammary cellular and tissue homeostasis. Systemically, unresolved UTI correlates with increased plasma levels of the metalloproteinase inhibitor, TIMP1, which controls extracellular matrix remodeling and neutrophil function. Treatment of nulliparous and post-lactation UTI-bearing female mice with a TIMP1 neutralizing antibody, restores mammary tissue normal homeostasis, thus providing evidence for a link between the systemic host response during UTI and mammary glandalterations.