58,045 results match your criteria Muscle Biopsy and the Pathology of Skeletal Muscle


Systemic antisense therapeutics inhibiting DUX4 expression ameliorates FSHD-like pathology in an FSHD mouse model.

Hum Mol Genet 2021 May 13. Epub 2021 May 13.

Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK.

Aberrant expression of the double homeobox 4 (DUX4) gene in skeletal muscle causes muscle deterioration and weakness in Facioscapulohumeral Muscular Dystrophy (FSHD). Since the presence of a permissive pLAM1 polyadenylation signal is essential for stabilization of DUX4 mRNA and translation of DUX4 protein, disrupting the function of this structure can prevent expression of DUX4. We and others have shown promising results using antisense approaches to reduce DUX4 expression in vitro and in vivo following local intramuscular administration. Read More

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Combined gene therapy via VEGF and mini-dystrophin synergistically improves pathologies in temporalis muscle of dystrophin/utrophin double knockout mice.

Hum Mol Genet 2021 May 13. Epub 2021 May 13.

Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA.

Duchenne muscular dystrophy (DMD) is a severe X-linked inherited muscular disorder characterized by the loss of dystrophin. We have previously shown that monogene therapy using the mini-dystrophin gene improves muscle function in DMD. However, chronic inflammation plays an important role in progressive muscle degeneration in DMD as well. Read More

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Long-term effect of human mini-dystrophin in transgenic mdx mice improves muscle physiological function.

FASEB J 2021 Jun;35(6):e21628

Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA, USA.

Duchenne muscular dystrophy (DMD) is a lethal genetic muscle disorder caused by recessive mutations in dystrophin gene, affecting 1/3000 males. Gene therapy has been proven to ameliorate dystrophic pathology. To investigate therapeutic benefits from long-term effect of human mini-dystrophin and functional outcomes, transgenic mdx mice (Tg-mdx) containing a single copy of human mini-dystrophin (∆hDys3849) gene, five rods (Rods1-2, Rods22-24), and two hinges (H1 and H4) driven by a truncated creatine-kinase promoter (dMCK) in a recombinant adeno-associated viral vector (rAAV) backbone, were generated and used to determine gene expression and improvement of muscle function. Read More

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Mechanics of dystrophin deficient skeletal muscles in very young mice and effects of age.

Am J Physiol Cell Physiol 2021 May 12. Epub 2021 May 12.

Department of Medicine, Baylor College of Medicine, Houston, Texas, 77030, United Statesgrid.39382.33.

The MDX mouse is an animal model of Duchenne muscular dystrophy, a human disease marked by an absence of the cytoskeletal protein, dystrophin. We hypothesized that (1) dystrophin serves a complex mechanical role in skeletal muscles by contributing to passive compliance, viscoelastic properties, and contractile force production and (2) age is a modulator of passive mechanics of skeletal muscles of the MDX mouse. Using an in vitro biaxial mechanical testing apparatus, we measured passive length-tension relationships in the muscle fiber direction as well as transverse to the fibers, viscoelastic stress-relaxation curves, and isometric contractile properties. Read More

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Loss of dystrophin expression in skeletal muscle is associated with senescence of macrophages and endothelial cells.

Am J Physiol Cell Physiol 2021 May 12. Epub 2021 May 12.

Department of Applied Human Sciences, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canadagrid.139596.1.

Cellular senescence is the irreversible arrest of normally dividing cells and is driven by cell cycle inhibitory proteins such as p16, p21 and p53. When cells enter senescence, they secrete a host of proinflammatory factors known as the senescence associated secretory phenotype which has deleterious effects on surrounding cells and tissues. Little is known of the role of senescence in Duchenne Muscular Dystrophy (DMD), the fatal X-linked neuromuscular disorder typified by chronic inflammation, extracellular matrix remodeling and a progressive loss in muscle mass and function. Read More

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Biallelic Pathogenic Variants in Associated With Congenital Myopathy.

Neurol Genet 2021 Jun 26;7(3):e589. Epub 2021 Apr 26.

Division of Neurology and Developmental Neuroscience (D.G.C., I.H., D.P., T.L.), Department of Pediatrics, Baylor College of Medicine, Houston, TX; Texas Children's Hospital (D.G.C., I.H., D.P., J.R.L.), Houston, TX; Department of Molecular and Human Genetics (D.G.C., J.F., I.H., Z.C.A., H.D., R.A.G., D.M., D.P., J.E.P., J.R.L.), Baylor College of Medicine, Houston, TX; Human Genome Sequencing Center (S.N.J., R.A.G., J.R.L.), Baylor College of Medicine, Houston, TX; Department of Pediatrics (D.M.), Faculty of Medicine, Kuwait University, Safat, Kuwait; Division of Child and Adolescent Neurology (P.M.), Department of Pediatrics, University of Texas Health Science Center, Houston, TX; Pathology and Laboratory Medicine (M.B.B.), University of Texas Health Science Center at Houston-McGovern Medical School, Houston, TX; and Department of Pediatrics (J.R.L.), Baylor College of Medicine, Houston, TX.

Objective: Pathogenic variants in , the gene encoding fast skeletal muscle troponin T, were first described in autosomal dominant distal arthrogryposis type 2B2. Recently, a homozygous splice site variant, c.681+1G>A, was identified in a patient with nemaline myopathy and distal arthrogryposis. Read More

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Triadin Decrease Impairs the Expression of E-C Coupling Related Proteins in Muscles of MPTP-Induced Parkinson's Disease Mice.

Front Neurosci 2021 22;15:649688. Epub 2021 Apr 22.

Department of Korean Medicine, Sangji University, Wonju, South Korea.

Parkinson's disease (PD), caused by destruction of dopaminergic neurons in the brain, leads to motor symptoms like bradykinesia, tremor, and walking impairments. While most research effort focuses on changes in neuronal pathology we examined how muscle proteins were altered in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. A Ca release channel complex, consisting of ryanodine receptors (RYR), triadin (TRDN), and calsequestrin (CSQ1), is important for excitation-contraction coupling in the sarcoplasmic reticulum membrane in muscles. Read More

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Increased myocellular lipid and IGFBP-3 expression in a pre-clinical model of pancreatic cancer-related skeletal muscle wasting.

J Cachexia Sarcopenia Muscle 2021 May 7. Epub 2021 May 7.

Department of Surgery, University of Rochester Medical Center, Rochester, New York, USA.

Background: Skeletal muscle wasting (SMW) in cancer patients is associated with increased morbidity, mortality, treatment intolerance and discontinuation, and poor quality of life. This is particularly true for patients with pancreatic ductal adenocarcinoma (PDAC), as over 85% experience SMW, which is responsible for ~30% of patient deaths. While the established paradigm to explain SMW posits that muscle catabolism from systemic inflammation and nutritional deficiencies, the cause of death, and the cellular and molecular mechanisms responsible remain to be elucidated. Read More

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A rare case of intramuscular angioma involving the medial rectus muscle.

Orbit 2021 May 6:1-6. Epub 2021 May 6.

Department of Ophthalmology and Pathology, University of Ottawa and the Ottawa Hospital, Ottawa, Ontario, Canada.

Benign benign vascular tumors (e.g., hemangiomas) and malformations are commonly encountered lesions in all ages of life, especially in infancy and childhood. Read More

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Current Update on the Diagnosis, Management and Pathogenesis of Elastofibroma Dorsi.

Anticancer Res 2021 May;41(5):2211-2215

Department of Orthopaedic Surgery, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.

Elastofibroma dorsi is an uncommon benign fibroblastic pseudotumor that typically occurs in the subscapular region of middle-aged or older individuals. The pathogenesis is still unclear and a matter of debate. Magnetic resonance imaging can be used as a first-line investigation of the lesion and reveals a lenticular soft-tissue mass with a signal intensity similar to that of skeletal muscle interlaced with strands of fat. Read More

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Mechanisms of exercise as a preventative measure to muscle wasting.

Am J Physiol Cell Physiol 2021 May 5. Epub 2021 May 5.

Florida Institute for Human & Machine Cognition, Pensacola, FL; Department of Cell, Developmental, and Integrative Biology; UAB Center for Exercise Medicine; Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, United States.

Skeletal muscle is the most abundant tissue in healthy individuals and it has important roles in health beyond voluntary movement. The overall mass and energy requirements of skeletal muscle require it to be metabolically active and flexible to multiple energy substrates. The tissue has evolved to be largely load-dependent and it readily adapts in a number of positive ways to repetitive overload, such as various forms of exercise training. Read More

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Wasting Away: AJP Cell Initiates Thematic Reviews on Skeletal Muscle Wasting.

Am J Physiol Cell Physiol 2021 May 5. Epub 2021 May 5.

Dept. of Pathology and Molecular Medicine, McMaster University, Hamilton ON, Canada.

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Human muscle production in vitro from pluripotent stem cells: Basic and clinical applications.

Semin Cell Dev Biol 2021 Apr 30. Epub 2021 Apr 30.

Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA; Department of Genetics, Harvard Medical School, Boston, MA, USA; Harvard Stem Cell Institute, Boston, MA, USA. Electronic address:

Human pluripotent stem cells (PSCs), which have the capacity to self-renew and differentiate into multiple cell types, offer tremendous therapeutic potential and invaluable flexibility as research tools. Recently, remarkable progress has been made in directing myogenic differentiation of human PSCs. The differentiation strategies, which were inspired by our knowledge of myogenesis in vivo, have provided an important platform for the study of human muscle development and modeling of muscular diseases, as well as a promising source of cells for cell therapy to treat muscular dystrophies. Read More

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The cytokine interleukin-11 crucially links bone formation, remodeling and resorption.

Cytokine Growth Factor Rev 2021 Apr 24;60:18-27. Epub 2021 Apr 24.

Department of Pathology, Otto-von-Guericke-University Magdeburg, Medical Faculty, Magdeburg, Germany. Electronic address:

Bone development is a complex process that requires the activity of several different signaling pathways and cell types. It involves the coordinated action of osteoclasts (cells that are capable of resorbing bone), osteoblasts (cells that are able to form bone), osteocytes (cells that form a syncytial network within the bone), skeletal muscle cells and the bone marrow. In recent years, the cytokine interleukin-11 (IL-11), a member of the IL-6 family of cytokines, has emerged as an important regulatory protein for bone formation, remodeling and resorption. Read More

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Case Report and Review of the Literature: A New and a Recurrent Variant in the Gene Are Associated With Isolated Lethal Hypertrophic Cardiomyopathy, Hyperlactatemia, and Pulmonary Hypertension in Early Infancy.

Front Pediatr 2021 16;9:660076. Epub 2021 Apr 16.

Department of Medical Genetics, Kepler University Hospital Med Campus IV, Johannes Kepler University Linz, Linz, Austria.

Mitochondriopathies represent a wide spectrum of miscellaneous disorders with multisystem involvement, which are caused by various genetic changes. The establishment of the diagnosis of mitochondriopathy is often challenging. Recently, several mutations of the gene encoding the mitochondrial valyl-tRNA synthetase were associated with early onset encephalomyopathies or encephalocardiomyopathies with major clinical features such as hypotonia, developmental delay, brain MRI changes, epilepsy, hypertrophic cardiomyopathy, and plasma lactate elevation. Read More

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Inflammatory leiomyosarcoma of the head and neck: Case report.

Int J Surg Case Rep 2021 Apr 27;82:105907. Epub 2021 Apr 27.

Division of Anatomical Pathology, Faculty of Health Sciences, University of Cape Town, South Africa; PathCare, Claremont, Cape Town, South Africa.

Introduction And Importance: Primary sarcomas in the head and neck region are rare. Inflammatory leiomyosarcoma was first described in 1995. The case reported herein is the first reported inflammatory leiomyosarcoma occurring in the head and neck. Read More

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Danon disease: a case report and literature review.

Diagn Pathol 2021 May 1;16(1):39. Epub 2021 May 1.

Department of Cardiology, Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, 210008, P.R. China.

Background: Danon disease (DD) is a rare x-linked dominant multisystemic disorder with a clinical triad of severe cardiomyopathy, skeletal myopathy, and mental retardation. It is caused by a defect in the lysosomal-associated membrane protein-2 (LAMP2) gene, which leads to the formation of autophagic vacuoles containing glycogen granule deposits in skeletal and cardiac muscle fibers. So far, more than 50 different mutations in LAMP2 have been identified. Read More

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A Perspective on Accelerated Aging Caused by the Genetic Deficiency of the Metabolic Protein, OPA1.

Front Neurol 2021 13;12:641259. Epub 2021 Apr 13.

Mitochondria and Vision Lab, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom.

Autosomal Dominant Optic Atrophy (ADOA) is an ophthalmological condition associated primarily with mutations in the gene. It has variable onset, sometimes juvenile, but in other patients, the disease does not manifest until adult middle age despite the presence of a pathological mutation. Thus, individuals carrying mutations are considered healthy before the onset of clinical symptoms. Read More

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Age-Dependent Dysregulation of Muscle Vasculature and Blood Flow Recovery after Hindlimb Ischemia in the Model of Duchenne Muscular Dystrophy.

Biomedicines 2021 Apr 27;9(5). Epub 2021 Apr 27.

Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland.

Duchenne muscular dystrophy (DMD), caused by a lack of functional dystrophin, is characterized by progressive muscle degeneration. Interestingly, dystrophin is also expressed in endothelial cells (ECs), and insufficient angiogenesis has already been hypothesized to contribute to DMD pathology, however, its status in mice, a model of DMD, is still not fully clear. Our study aimed to reveal angiogenesis-related alterations in skeletal muscles of mice compared to wild-type (WT) counterparts. Read More

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Skeletal Muscle Proteomic Profile Revealed Gender-Related Metabolic Responses in a Diet-Induced Obesity Animal Model.

Int J Mol Sci 2021 Apr 28;22(9). Epub 2021 Apr 28.

Department of Biomedical Sciences for Health, University of Milan, 20090 Segrate, Italy.

Obesity is a chronic, complex pathology associated with a risk of developing secondary pathologies, including cardiovascular diseases, cancer, type 2 diabetes (T2DM) and musculoskeletal disorders. Since skeletal muscle accounts for more than 70% of total glucose disposal, metabolic alterations are strictly associated with the onset of insulin resistance and T2DM. The present study relies on the proteomic analysis of gastrocnemius muscle from 15 male and 15 female C56BL/J mice fed for 14 weeks with standard, 45% or 60% high-fat diets (HFD) adopting a label-free LC-MS/MS approach followed by bioinformatic pathway analysis. Read More

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Skeletal Muscle-Adipose Tissue-Tumor Axis: Molecular Mechanisms Linking Exercise Training in Prostate Cancer.

Int J Mol Sci 2021 Apr 25;22(9). Epub 2021 Apr 25.

Tumour & Microenvironment Interactions Group, INEB-Institute of Biomedical Engineering, i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-153 Porto, Portugal.

Increased visceral adiposity may influence the development of prostate cancer (PCa) aggressive tumors and cancer mortality. White adipose tissue (WAT), usually referred to as periprostatic adipose tissue (PPAT), surrounds the prostatic gland and has emerged as a potential mediator of the tumor microenvironment. Exercise training (ET) induces several adaptations in both skeletal muscle and WAT. Read More

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Phosphatidylserine Supplementation as a Novel Strategy for Reducing Myocardial Infarct Size and Preventing Adverse Left Ventricular Remodeling.

Int J Mol Sci 2021 Apr 22;22(9). Epub 2021 Apr 22.

Department of Intensive Care and Intermediate Care, University Hospital, RWTH Aachen University, 52074 Aachen, Germany.

Phosphatidylserines are known to sustain skeletal muscle activity during intense activity or hypoxic conditions, as well as preserve neurocognitive function in older patients. Our previous studies pointed out a potential cardioprotective role of phosphatidylserine in heart ischemia. Therefore, we investigated the effects of phosphatidylserine oral supplementation in a mouse model of acute myocardial infarction (AMI). Read More

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Treatment of Stress Urinary Incontinence with Muscle Stem Cells and Stem Cell Components: Chances, Challenges and Future Prospects.

Int J Mol Sci 2021 Apr 12;22(8). Epub 2021 Apr 12.

Department of Urology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland.

Urinary incontinence (UI) is a major problem in health care and more than 400 million people worldwide suffer from involuntary loss of urine. With an increase in the aging population, UI is likely to become even more prominent over the next decades and the economic burden is substantial. Among the different subtypes of UI, stress urinary incontinence (SUI) is the most prevalent and focus of this review. Read More

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Effect of COVID-19 Pandemic on the Change in Skeletal Muscle Mass in Older Patients with Type 2 Diabetes: A Retrospective Cohort Study.

Int J Environ Res Public Health 2021 04 15;18(8). Epub 2021 Apr 15.

Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.

: The aim of this study was to investigate the effect of the coronavirus disease (COVID-19) pandemic restrictions on the change in muscle mass in older patients with type 2 diabetes (T2D), who were not infected with COVID-19. In this retrospective cohort study, data were obtained from outpatients who underwent bioelectrical impedance analysis at least twice before April 2020 and at least once thereafter. Skeletal muscle mass index (SMI, kg/m) was calculated as appendicular muscle mass (kg) divided by height squared (m). Read More

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Chronic Ouabain Prevents Na,K-ATPase Dysfunction and Targets AMPK and IL-6 in Disused Rat Soleus Muscle.

Int J Mol Sci 2021 Apr 10;22(8). Epub 2021 Apr 10.

Department of General Physiology, St. Petersburg State University, 199034 St. Petersburg, Russia.

Sustained sarcolemma depolarization due to loss of the Na,K-ATPase function is characteristic for skeletal muscle motor dysfunction. Ouabain, a specific ligand of the Na,K-ATPase, has a circulating endogenous analogue. We hypothesized that the Na,K-ATPase targeted by the elevated level of circulating ouabain modulates skeletal muscle electrogenesis and prevents its disuse-induced disturbances. Read More

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Potential Roles of the WNT Signaling Pathway in Amyotrophic Lateral Sclerosis.

Cells 2021 Apr 8;10(4). Epub 2021 Apr 8.

Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.

The WNT signaling pathway plays an important role in the physiological and pathophysiological processes of the central nervous system and the neurodegenerative disease amyotrophic lateral sclerosis (ALS). We reviewed the literature pertinent to WNT/β-catenin signaling in ALS from cellular studies, animal models, and human clinical trials. WNT, WNT receptors, and other components of the WNT signaling pathway are expressed in both ALS patients and transgenic mice, and are involved in the pathogenesis of ALS. Read More

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Altered Metabolic Flexibility in Inherited Metabolic Diseases of Mitochondrial Fatty Acid Metabolism.

Int J Mol Sci 2021 Apr 6;22(7). Epub 2021 Apr 6.

Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center-University of Freiburg, 79106 Freiburg, Germany.

In general, metabolic flexibility refers to an organism's capacity to adapt to metabolic changes due to differing energy demands. The aim of this work is to summarize and discuss recent findings regarding variables that modulate energy regulation in two different pathways of mitochondrial fatty metabolism: β-oxidation and fatty acid biosynthesis. We focus specifically on two diseases: very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) and malonyl-CoA synthetase deficiency (acyl-CoA synthetase family member 3 (ACSF3)) deficiency, which are both characterized by alterations in metabolic flexibility. Read More

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A Review of the Role of Endo/Sarcoplasmic Reticulum-Mitochondria Ca Transport in Diseases and Skeletal Muscle Function.

Int J Environ Res Public Health 2021 Apr 7;18(8). Epub 2021 Apr 7.

School of Sport Science, Beijing Sport University, Beijing 100084, China.

The physical contact site between a mitochondrion and endoplasmic reticulum (ER), named the mitochondria-associated membrane (MAM), has emerged as a fundamental platform for regulating the functions of the two organelles and several cellular processes. This includes Ca transport from the ER to mitochondria, mitochondrial dynamics, autophagy, apoptosis signalling, ER stress signalling, redox reaction, and membrane structure maintenance. Consequently, the MAM is suggested to be involved in, and as a possible therapeutic target for, some common diseases and impairment in skeletal muscle function, such as insulin resistance and diabetes, obesity, neurodegenerative diseases, Duchenne muscular dystrophy, age-related muscle atrophy, and exercise-induced muscle damage. Read More

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An update on immunohistochemical and molecular genetic markers of selected soft tissue tumors.

Authors:
Michael Michal

Cesk Patol 2021 ;57(1):19-29

Recent years have brought an immense increase of knowledge regarding the molecular genetic background of mesenchymal tumors which in turn has significantly expanded the repertoire of molecular markers available for the routine diagnostic practice. This progress has also been followed by a rising number of available immunohistochemical markers useful for the diagnosis of soft tissue neoplasia. Both lineage specific and tumor-specific immunohistochemical antibodies have been discovered and subsequently tested in the surgical pathology practice. Read More

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