Lobular Formation Research Articles

Paleopathology of the skull of Santorio Santorio, father of modern clinical experimental physiology.

The University of Padua (Italy) preserves the skull of Santorio Santorio, father of the modern clinical experimental physiology. A recent study performed with modern anthropological methods and medical instruments (CT scan) revealed the presence of a lobular formation in the left temporal bone, with an irregular morphology, internal bone sequestrum, a well-defined non-continuous sclerosis and both internal and external thinning of the cranial plate. Three oval depressions observed in the cranial vault, edentulism and moderate osteoarthritis of the temporomandibular joint were also investigated. The lobular formation was an epidermoid cyst and the oval depressions were the result of other cysts. The edentulism was consistent with some metabolic deficiency or disease, whilst the osteoarthritis appeared to be the result of antemortem tooth loss. This study allowed to investigate a complex and peculiar palaeopathological picture, linked to a piece of the history of the University of Padua.

Cell-extracellular matrix interactions in the fluidic phase direct the topology and polarity of self-organized epithelial structures.

IntroductionIn vivo, cells are surrounded by extracellular matrix (ECM). To build organs from single cells, it is generally believed that ECM serves as scaffolds to coordinate cell positioning and differentiation. Nevertheless, how cells utilize cell‐ECM interactions for the spatiotemporal coordination to different ECM at the tissue scale is not fully understood.MethodsHere, using in vitro assay with engineered MDCK cells expressing H2B‐mCherry (nucleus) and gp135/Podocalyxin‐GFP (apical marker), we show in multi‐dimensions that such coordination for epithelial morphogenesis can be determined by cell‐soluble ECM interaction in the fluidic phase.ResultsThe coordination depends on the native topology of ECM components such as sheet‐like basement membrane (BM) and type I collagen (COL) fibres: scaffold formed by BM (COL) facilitates a close‐ended (open‐ended) coordination that leads to the formation of lobular (tubular) epithelium. Further, cells form apicobasal polarity throughout the entire lobule/tubule without a complete coverage of ECM at the basal side, and time‐lapse two‐photon scanning imaging reveals the polarization occurring early and maintained through the lobular expansion. During polarization, gp135‐GFP was converged to the apical surface collectively in the lobular/tubular structures, suggesting possible intercellular communications. Under suspension culture, the polarization was impaired with multi‐lumen formation in the tubules, implying the importance of ECM biomechanical microenvironment.ConclusionOur results suggest a biophysical mechanism for cells to form polarity and coordinate positioning at tissue scale, and in engineering epithelium through cell‐soluble ECM interaction and self‐assembly.

MEA6 Deficiency Impairs Cerebellar Development and Motor Performance by Tethering Protein Trafficking.

Meningioma expressed antigen 6 (MEA6), also called cutaneous T cell lymphoma-associated antigen 5 (cTAGE5), was initially found in tumor tissues. MEA6 is located in endoplasmic reticulum (ER) exit sites and regulates the transport of collagen, very low density lipoprotein, and insulin. It is also reported that MEA6 might be related to Fahr’s syndrome, which comprises neurological, movement, and neuropsychiatric disorders. Here, we show that MEA6 is critical to cerebellar development and motor performance. Mice with conditional knockout of MEA6 (Nestin-Cre;MEA6F/F) display smaller sizes of body and brain compared to control animals, and survive maximal 28 days after birth. Immunohistochemical and behavioral studies demonstrate that these mutant mice have defects in cerebellar development and motor performance. In contrast, PC deletion of MEA6 (pCP2-Cre;MEA6F/F) causes milder phenotypes in cerebellar morphology and motor behaviors. While pCP2-Cre;MEA6F/F mice have normal lobular formation and gait, they present the extensive self-crossing of PC dendrites and damaged motor learning. Interestingly, the expression of key molecules that participates in cerebellar development, including Slit2 and brain derived neurotrophic factor (BDNF), is significantly increased in ER, suggesting that MEA6 ablation impairs ER function and thus these proteins are arrested in ER. Our study provides insight into the roles of MEA6 in the brain and the pathogenesis of Fahr’s syndrome.

Dedifferentiated liposarcoma of the gallbladder: first reported case

BackgroundLiposarcoma of the gallbladder is an extremely rare sarcoma, with only five cases reported in the literature according to our knowledge.Case presentationA 71-year-old woman was referred to the Surgical Oncology Division of Napoleão Laureano Hospital (João Pessoa, PB, Brazil) due to a solid mass at the right side of the abdomen and fever, with no signs of jaundice. Abdominal ultrasonography and computed tomography (CT) evidenced an extensive gallbladder lobular formation adhered to the inferior border of the right hepatic lobe and cholelithiasis. The CT report suggested gallbladder liposarcoma. A cholecystectomy associated with resection of segments IV-B and V of the liver were performed. Intraoperative frozen sections were compatible with gallbladder sarcoma. Anatomopathological examination and immunohistochemistry confirmed dedifferentiated liposarcoma with foci of heterologous leiomyosarcomatous differentiation and undifferentiated fusocellular areas of high histological grade.ConclusionThis is the first case of dedifferentiated liposarcoma of the gallbladder to be reported.

Aspirin abrogates impairment of mammary gland differentiation induced by early in life second-hand smoke in mice.

Epidemiological studies show that there is limited evidence that tobacco smoking causes breast cancer in humans. In rodents, many tobacco smoke chemicals cause mammary gland tumors. This study evaluated the mammary gland differentiation in mice exposed to environmental cigarette smoke (ECS), using 3R4F Kentucky reference cigarettes, starting after birth and continuing daily for 10 weeks (total particulate exposure 95 mg/m3; CO 610 ppm). We also analyzed the effects of oral administration of non-steroidal anti-inflammatory drugs (NSAIDs), aspirin (1600 mg/kg) or naproxen (320 mg/kg), on mammary gland differentiation, either in unexposed or ECS-exposed mice. The ECS exposure caused delay of mammary glands development. We speculate that this delay may result from aryl hydrocarbon receptor (AHR) signaling activation, which has an antiestrogenic effect and crosstalk to the estrogen metabolism pathway. Similarly, naproxen impaired gland differentiation in unexposed and ECS-exposed mice, while aspirin hindered its development only in unexposed mice. The lack of differentiation induced by the NSAIDs could be explained by their antiestrogenic effect through inhibition of aldo-keto reductases. In ECS-exposed animals, aspirin induced intense lobular formation, which could indicate that aspirin is counteracting the AHR signaling induced by ECS. Based on the differentiation induced by aspirin in ECS-exposed animals, we postulate that these mice would be less susceptible to mammary carcinogenesis. Our results suggest that exposure to smoke at an early age impairs the development of the mammary gland, thus resulting in a longer period of susceptibility and increased risk of breast cancer. However, addition of aspirin can abrogate this effect.

The ecology of the tropical salamander, Bolitoglossa subpalmata, in Costa Rica.

The ecology of the tropical salamander, Bolitoglossa subpalmata, in Costa Rica.

Large pseudoangiomatous stromal hyperplasia complicated with gynecomastia and lobular differentiation in a male breast.

Pseudoangiomatous stromal hyperplasia (PASH) is a benign lesion often observed in parts of the mammary stroma in a variety of breast diseases. It is characterized by stromal myofibroblastic proliferation that possesses irregularly anastomosing slit-like pseudovascular spaces lined by a layer of spindle cells. PASH commonly occurs in premenopausal women; however, it has also been observed in men with gynecomastia. Although tumor-forming lesions are rare, we report on a case with a large PASH in a male breast complicated with gynecomastia. Imaging showed a tumor with a diameter of >10 cm in the left breast, and aspiration cytology revealed a benign lesion. Since the tumor was large and gradually increased in size, a simple mastectomy was performed. The tumorous lesion was diagnosed as PASH based on the pathological and immunohistological findings. It was complicated by gynecomastia with acinar and lobular formation, which resembled female mammary gland secretory activity that is observed during lactation.

Eosinophil extracellular DNA trap cell death mediates lytic release of free secretion-competent eosinophil granules in humans

AbstractEosinophils release their granule proteins extracellularly through exocytosis, piecemeal degranulation, or cytolytic degranulation. Findings in diverse human eosinophilic diseases of intact extracellular eosinophil granules, either free or clustered, indicate that eosinophil cytolysis occurs in vivo, but the mechanisms and consequences of lytic eosinophil degranulation are poorly understood. We demonstrate that activated human eosinophils can undergo extracellular DNA trap cell death (ETosis) that cytolytically releases free eosinophil granules. Eosinophil ETosis (EETosis), in response to immobilized immunoglobulins (IgG, IgA), cytokines with platelet activating factor, calcium ionophore, or phorbol myristate acetate, develops within 120 minutes in a reduced NADP (NADPH) oxidase-dependent manner. Initially, nuclear lobular formation is lost and some granules are released by budding off from the cell as plasma membrane–enveloped clusters. Following nuclear chromatolysis, plasma membrane lysis liberates DNA that forms weblike extracellular DNA nets and releases free intact granules. EETosis-released eosinophil granules, still retaining eosinophil cationic granule proteins, can be activated to secrete when stimulated with CC chemokine ligand 11 (eotaxin-1). Our results indicate that an active NADPH oxidase-dependent mechanism of cytolytic, nonapoptotic eosinophil death initiates nuclear chromatolysis that eventuates in the release of intact secretion-competent granules and the formation of extracellular DNA nets.

A case of membranoproliferative glomerulonephritis developed over twentyyears with three different findings of renal pathology.

A 31-year-old woman with proteinuria, hypocomplementemia, rheumatoid factor, and high serum polyclonal IgM concentration was admitted to our hospital for renal biopsy. She had a past history of two renal biopsies. When she was 12years old, she developed proteinuria, microscopic hematuria, and hypocomplementemia. She was diagnosed as having 'IgM nephropathy' based on minor glomerular abnormalities as determined by light microscopy and IgM and C3 deposition in the mesangial region by immunofluorescence microscopy at the first biopsy. Despite corticosteroid treatment, her proteinuria did not improve and she discontinued regular outpatient checkups. When she was 29years old and pregnant, she developed preeclampsia and, after delivery, a second renal biopsy was implemented. She was diagnosed as having progressed 'IgM nephropathy' with endotheliosis induced by preeclampsia. She was treated with angiotensin II receptor blocker and her proteinuria diminished; however, 1year after the delivery, she developed proteinuria again, along with microscopic hematuria and hypocomplementemia. A third renal biopsy was conducted at 31years of age and she was diagnosed as having membranoproliferative glomerulonephritis (MPGN) type I on the basis of diffuse mesangial proliferation, endocapillary hypercellularity with double contour of the capillary wall, and lobular formation in glomeruli, as determined by light microscopy. Immunofluorescence staining demonstrated deposits of C3, C4, C1q, and IgM in the mesangial region and capillary wall. She underwent corticosteroid therapy followed by normalization of urinalysis and serum complement level. Although she had initially been diagnosed with 'IgM nephropathy', she was finally diagnosed with secondary MPGN and was successfully treated by corticosteroid therapy.

Nrf2-deficient female mice develop lupus-like autoimmune nephritis

NF-E2-related factor 2 (Nrf2) is a basic leucine zipper transcriptional activator essential for the coordinate transcriptional induction of antioxidant enzymes and phase II drug metabolizing enzymes through the antioxidant response element/electrophile response element. The Nrf2-deficient mice were found to develop normally under standard laboratory conditions. However, upon closer examination, we found that aged female Nrf2-deficient mice displayed a shortened lifespan and developed severe glomerulonephritis. The present study investigated the glomerulonephritis findings in Nrf2-deficient mice. To evaluate glomerular lesions of Nrf2-deficient mice, histological and functional analyses were performed. The amounts of serum immunoglobulins, anti-double-stranded (ds) DNA antibody, and lipid peroxidation using thiobarbituric acid reactive substances (TBARS) also were measured. Nrf2-deficient female mice over 60 weeks of age developed severe nephritis characterized by cellular proliferation, lobular formation, crescent formation, and subepithelial electron-dense deposits. In immunofluorescent assays, Nrf2-deficient female mice showed mesangial deposits and massive granular deposits of IgG, IgM, and C3 along the capillary walls. Higher serum levels of IgG, anti-dsDNA antibody, lower creatinine clearance, and slight splenomegaly also were found in Nrf2-deficient female mice. A higher concentration of TBARS also was found in Nrf2-deficient female mice. These data indicate that the aged Nrf2-deficient female mice develop lupus-like autoimmune nephritis and suggest that nrf2 is one of the genes determining susceptibility to autoimmune disease. Analysis of nephritis in the Nrf2-deficient female mouse may clarify the mechanisms leading to the development of lupus disease.

A CASE WITH ACUTE RENAL FAILURE COMPLICATED BY WALDENSTRÖM'S MACROGLOBULINEMIA AND CRYOGLOBULINEMIA

We encountered a 53-year-old man associated with acute renal failure caused by Waldenström's macroglobulinemia and type I cryoglobulinemia. Treatment with prednisolone and cyclophosphamide induced a rapid recovery from acute renal failure. Renal histology revealed endocapillary proliferation and lobular formation with scattered subendothelial, amorphous and periodic acid-Schiff (PAS)-positive materials in the glomerular capillaries which were positive for IgM on immunofluorescence study. Although the exact mechanism for pathophysiology of acute renal failure remains unknown, treatment with prednisolone and cyclophosphamide could induce a rapid recovery from acute renal failure accompanied by Waldenström's macroglobulinemia and type I cryoglobulinemia.

Clinical, histopathologic and immunohistochemical studies of chronic sialectatic parotitis in childhood and adolescence

Chronic sialectatic parotitis (CSP) causes problems in differential diagnosis and therapy. CSP shows the typical clinical features of chronic recurrent parotitis and will be investigated histopathologically only after ultimative parotidectomy. The etiology and pathogenesis of these unspecific inflammations is still unknown. Therefore no causal therapy is available and a lot of different trials (sialogoga, gland massage, infrared light, antibiotics, antiphlogistics, Trasylol, duct occlusion, duct ligation, gland denervation, radiotherapy) are not successful in the long run. The salivary gland registry of the University of Hamburg (1965-1996) contains 22 infants and juvenile patients showing very severe courses of CSP. These cases have been investigated clinical (ultrasound, sialography), histopathological (paraffin embedded sections, histomorphometry of the ectatic duct lumina) and immunohistochemical (CK-MNF, AKTIN, KiM4) in a retrospective study to research the pathogenesis of CSP. Recurrent and always very dolent parotid swelling occurs between the age of 3 and 14 years for the first time. The courses vary from 3 months until 25 years. Local findings as well as ultrasound and sialographic features allow no certain differentiation of chronic recurrent parotitis. Conservative therapy fails in each case and leads to the necessity of surgical treatment. Histopathological three different stages of development can be observed: Initial stages show regular lobular architectonic structure of the parotid gland parenchyme with duct ectasies surrounded by slight inflammation of lymphocytes and plasmacells. Advanced stages are characterized by an increase of periductal inflammation and the appearance of lymphfollicels. Nearly complete lymphatic transformation of the parenchyme with destruction of the lobular formation dominates the terminal "immunologic" stage. Some cases show multiple myoepithelial islands within this lymphatic stroma typically observed in benign lymphoepithelial lesions. Whether bacteria nor primary obstructive changes can be observed. The histomorphometric analyses of the average and maximal luminal duct diameters show marked increase of 39% respectively 46% from and- vanced to terminal stages of CSP. Therefore the pathognomonic duct ectasies seem to depend on the progredient inflammation and are not due to a hereditary malformation of the duct system. Immunohistochemical terminal stages show follicular lymphatic hyperplasia (KiM4) expressing overshooting humoral immune reaction of MALT. Concerning the pathogenesis CSP corresponds to a immunopathological disorder of MALT and seems to be a prestage of benign lymphoepithelial lesion. Consequently important changes in the diagnosis and therapy of CSP lead to early histopathological investigation to differentiate the stage of inflammation. In stage III conservative parotidectomy should be carried out because spontaneous healing can not be expected. In contrast initial cases should be treated at first by glucocorticoids and immunosuppressives.

Branching Morphogenesis of Mouse Embryonic Submandibular Epithelia Cultured under Three Different Conditions: (mouse submandibular gland/epithelial branching/morphogenesis/collagenase/heparitinase/heparin/Matrigel).

To investigate how the mesenchyme interacts with the epithelium, we employed three different culture systems: System A, in which intact submandibular gland rudiments at the mid 13-day stage were cultured on Millipore filters; System B, in which the 13-day epithelium and mesenchyme were separated once with dispase, recombined again, and cultured on the filter; System C, in which the separated 13-day epithelium was clotted with Matrigel and cultured with the mesenchyme across the filter or in the presence of EGF instead of the mesenchyme. In Systems A and B, 13-day epithelia expanded and produced similar lobules with narrow clefts and stalk. When the 13-day epithelium was cultured in System C under the influence of the mesenchyme, it formed rather oval lobules with stalk that were superficially similar to those in System A, but narrow clefts, as seen in the intact early 13-day gland, were rarely found in System C. Furthermore, no long stalk formation was observed when EGF was introduced in place of the mesenchyme. A bacterial collagenase from Clostridium histolyticum gave a considerable inhibition of branching of the 13-day epithelium in Systems A and B, but no significant inhibition was observed in System C when the mesenchyme or EGF was employed as the source of diffusible factor(s). In contrast, although the 13-day epithelium was significantly resistant to the action of heparitinase I from Flavobacterium heparinum in Systems A and B, the enzyme almost completely inhibited the expansion and branching of the epithelium in System C. Judging from these observations, we conclude that the mechanisms of lobular formation in Systems A and B are not the same as those in System C, where the epithelium is clotted with basement membrane matrix components during tissue culture.

LYMPHOCYTE FORMATION IN THE THYMUS OF THE EMBRYONIC CHICK.

AbstractEmbryonic thymus provides a distinct advantage over the definitive thymus because the earliest formation of lymphocyte and lymphocytic precursors can be observed in a relatively simple and uncomplicated situation. Special cytological techniques combined with light, phase, and electron microscopy have been performed in this investigation involving over 150 chick embryos between 5 and 18 days of embryonic development.Sequential cytological changes in the development of the thymus into an active lymphocytopoietic organ indicate that lymphoblasts develop by the gradual proliferation and transformation of “undifferentiated” epithelial cells comprising the primordial thymus. Lymphoblastic transformation begins on the seventh day of embryonic development in the chick and is characterized by increased cytoplasmic and nucleolar basophilia and chromatin condensation. “Undifferentiated” epithelial cells undergo two distinct lines of differentiation between the seventh and tenth days: into lymphoblasts and into stellate reticular‐epithelial cells which constitute the organ parenchyma. All stages of lymphocytic maturation may be observed by 10–11 days as the thymus assumes a predominately lymphocytic character. Absence of lymphocytes or lymphocytic precursors in the connective tissue surrounding the embryonic thymus before and during the period of initial lymphoblastic transformation; presence of a continuous basement membrane surrounding the developing thymus; and absence of cells passing through this membrane during this phase of development indicate that the lymphocytic elements appearing in the embryonic thymus parenchyma are of epithelial rather than mesenchymal derivation. Although a contribution of mesenchymal elements to the lymphocytic population via vascular invasion and lobular formation in later stages of thymic development is unlikely, this question cannot be answered at this time. In spite of functional immunological distinctions between the lymphocytes of the chick thymus and bursa of Fabricius, the similarity of origin of the lymphocytic elements of these lympho‐epithelial organs is apparent.