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At least 19 recordsLinked to original sources
PubMed2026

Urban stormwater infrastructure as a microplastic superhighway: a critical review of transport dynamics, modelling, and mitigation across pavements and drainage networks.

This review examines the transport, fate, modelling, and mitigation of Microplastics (MPs) in urban stormwater infrastructure, with emphasis on pavements, runoff pathways, micro-drainage, and macro-drainage systems. Following a systematic review approach, more than 1000 records were screened and approximately 50 core studies were retained when they addressed urban stormwater or drainage-related MP transport with adequate methodological reporting; marine-only studies and biological-effect studies without direct relevance to transport processes were excluded. The evidence shows that stormwater systems function not merely as passive conduits but as dynamic reactive transport systems with temporary storage, where particle mobilisation, sedimentation, resuspension, and temporary retention regulate MP export. Road surfaces, especially high-traffic areas, are major reservoirs of tyre wear, road-marking, atmospheric, and litter-derived particles that are rapidly mobilised during rainfall. Conventional grab sampling may underestimate MP loads, which in some cases exceed treated wastewater effluent loads by up to six-fold. Drainage structures such as manholes can immobilise up to 17.3% of near-neutrally buoyant particles, while biofouling and aggregation may shift buoyant polymers from wash-load to bedload. Mitigation systems, including permeable pavements, bioretention, wetlands, and technical inserts, can achieve high removal of coarse MPs, but performance declines for fine particles below 100 µm. The review highlights the need for standardised flow-proportional sampling, physically informed modelling, and treatment-train strategies targeting both surface sources and in-network storage.

Microplastics↗
PubMed1979

Circulation of cerebrospinal fluid in the bullfrog, Rana catesbiana.

In order to demonstrate features of the cerebrospinal fluid (CSF) path in the amphibian, 2--6 microliters of either Evans Blue-albumin (EBA) or ferrocyanide were injected into the ventricular system of anesthetized bullfrogs. The animals were sacrificed 1 to 135 minutes after injection by either quick freezing (EBA injections) or fixative perfusion (ferrocyanide injections). The contents of the cranial and vertebral cavities were then examined grossly and histologically for distribution of the tracers. In all animals, the tracers were seen throughout the ventricular cavity and in the subarachnoid space surrounding the caudal hindbrain. The site of communication between these two fluid spaces was the posterior tela of the hindbrain. Within this tela, "pores" were found between groups of pavement-like ependymal cells. In many animals, tracer was also observed in the vertebral subarachnoid and epidural spaces, adjacent to spinal nerve roots. In three EBA-injected animals, this tracer was also seen in the subcardinal lymph spaces. These findings suggest that the subarachnoid space in the bullfrog communicates functionally with the ventricular system by way of specialized "pores" in the posterior tela of the hindbrain. There is also indication of movement of fluid within the subarachnoid space which is predominately caudal in direction, with a primary absorptive path for CSF that consists of a perineural route to the lymphatic system.

Animals↗
PubMed1977

Altered morphology and increased cell adhesiveness of chinese hamster ovary cells cultured on fibrin.

Chinese hamster ovary cells cultivated on fibrin exhibited different characteristic from cells growing on plastic. While sparsely plated cells on plastic dishes had an epithelioid morphology, cells on fibrin assumed a round shape and then converted to a stretched form with protruded processes that increased with cell density. Within a few days, cells fibrinolysed adjacent fibrin and returned to the morphology seen in plastic dishes. When fibrinolysis was inhibited by epsilon-aminocaproic acid (EACA), cells continued to grow on the fibrin for a longer period and showed dense, criss-crossed fibroblast-type congestion. Whereas, cells on plastic maintained pavement-like epitheloid appearance when they grew to a confluent monolayer. The other altered characteristics on fibrin was increased accumulation of cells in multilayers. Normally as Chinese hamster cells on plastic proliferate, many cells float into the medium instead of piling up after they form a monolayer. On the other hand, cells on fibrin, being maintained by the addition of EACA, remained adherent, piling up multilayers instead of floating into the medium. A possible explanation of these findings is that the surface properties of the stretched cells on fibrin are altered to make them more adhesive. A possible link of these characteristics of the cells on fibrin to tumor cell behavior in vivo is dicussed.

Aminocaproates↗
PubMed1977

Maintenance and induction of morphological differentiation in dissociated mammary epithelium on floating collagen membranes.

Dissociated normal mammary epithelial cells from prelactating mice were plated on different substrates in various medium-serum-hormone combinations to find conditions that would permit maintenance of morphological differentiation. Cells cultured on floating collagen membranes in medium containing insulin, hydrocortisone and prolactin maintain differentiation through 1 month in culture. The surface cells form a continous epithelial pavement. Some epithelial cells below the surface layer rearrange themselves to form alveolus-like structures. Cells at both sites display surface polarization; microvilli and tight junctions are present at their medium-facing of luminal surface and a basal lamina separates the epithelial components from the gel and stromal cells. Occasional myoepithelial cells, characterized by myofilaments and plasmalemmmal vesicles, are identified at the basal surface of the secretory epithelium. In contrast, cells cultured on plastic, glass or collagen gels attached to Petri dishes form a confluent epithelial sheet showing surface polarization, but lose secretory and myoepithelial specializations. If these dedifferentiated cells are subsequently maintained on floating collagen membranes, they redifferentiate. There is little DNA synthesis in cells on collagen gels, in contrast to Petri-dish controls. Protein synthesis in cells on floating collagen membranes increases over TO values and remains constant through 7 days in culture whereas it decreases on attached gels; however, if the gels are freed to float, protein synthesis increases sharply and parallels that seen on floating membranes.

Animals↗
PubMed1979

Establishment and characterization of a new endometrial cancer cell line (SCRC-1).

A new human endometrial cell line, SCRC-1, has been established from a uterine adenocarcinoma. During a period of 57 weeks in culture, the SCRC-1 cells have been passaged over 100 times. Cultures have an epitheloid morphology, high mitotic activity, and a tendency to form multiple cell layers. The cells are polygonal and are arranged in pavement-like fashion. Most have multiple nucleoli, some are multinucleated, and all have heavily vacuolated cytoplasm. Pretreatment with iododeoxyuridine did not reveal viral markers by cocultivation or immunofluorescence techniques. Karyologic studies indicate that the SCRC11 cell line is essentially diploid with a small subpopulation of tetraploid cells. Over a period of 20 weeks, 1 of 14 athymic nude mice inoculated with SCRC-1 cells developed a tumor which histologically closely resembled the original human tumor. Cells were subsequently propagated from this tumor and the resulting epitheloid-like cell line was designated SCRC-1, Tu 1.

Adenocarcinoma↗
PubMed1979

Microscopic changes in rat tongue following experimental cryosurgery.

Histological changes were studied in the rat tongue for varying periods of time up to 14 days following the application of a cryoprobe to the dorsal surface of rat tongue. Within minutes of the application, focal subepithelial vesiculation and hyperemia occurred. At 3 h there was evidence of damage to capillary walls, resulting in hemorrhage. Arterioles and venules were thrombosed and there were degenerative changes in the muscle layer of their walls. At 6 h ventral epithelium showed evidence of damage. At this stage vessel walls were pavemented with neutrophilic polymorphonuclear leukocytes (PMN) and some of the latter were seen in the vessel walls. At 24 h abundant PMN, many of them necrotic, were present in the vessel walls, apparently unable to pass through them. At 48 h numerous PMN were seen adhering to degenerating muscle fibers. By 4 days necrotic changes extended through the full thickness of the tongue, but concurrently it was observed that the larger thrombosed vessels were becoming recanalized. At 5 days repair by granulation tissue was taking place and at 6 days the vasculature was virtually reconstituted. By 14 days healing was complete.

Animals↗
PubMed1978

225 skateboard injuries in children.

Among 225 skateboard accidents treated at the Children's Hospital, Sheffield, in 8 months from August 1977, there were 92 fractures (40.9 per cent), of which 19 required manipulation under general anesthetic. Most involved the upper limb. Next most frequent were lacerations, bruises, abrasions, and injuries of joints and soft tissues. Four children had concussions (one with a fractured skull), 8 others had minor head injury, and 23 had soft tissue injuries of the head and neck. As for the reasons for the accidents, 20 per cent were due to hitting a stone, 10 per cent to a hole or bump in the pavement, 8 per cent to collisions, and three accidents to faults in the skateboards. Sixteen of the children were injured on the first day of their skateboarding. The role of protective clothing was uncertain. The city has no skateboard parks. Injuries due to skateboards were compared to injuries due to playground equipment.

Adolescent↗
PubMed1978

Endothelial lesions associated with vascular clamping--surface micropathology by scanning electron microscopy.

The endothelial cell pavement in normal blood vessels is very fragile. In cardiovascular surgery, the need for secure clamping of the aorta results in trauma which may be followed by thrombosis or occlusion. Various types of vascular clamps and other related devices offered commercially were clinically investigated in canine models and their effects on the vascular endothelium were ascertained with the aid of scanning electron microscopy. On the basis of these studies, the Fogarty silicone filled clamp appeared to be the least traumatic. However, further technical developments in this area are needed in order to obtain a completely atraumatic method of temporarily closing major blood vessels.

Animals↗
PubMedDate not supplied

[Influence of tobacco smoking on the development of experimental pulmonary tuberculosis].

The present investigation was designed to the study, in rabbits, of morphologic and enzymatic pulmonary alterations produced by tobacco smoke and the course of tuberculosis under these conditions. The histologic examination revealed muciparous hyperplasia and pavementing metaplasia of the bronchic epithelium, accompanied by interstitial cellular reactions, reticulin, fibrilogenesis, atelectasis, emphysema and marked debility of the animals. In the animals treated with tobacco smoke the tuberculous lesions were very extensive and had an exudative-necrotic character. Under the influence of chemotherapy, applied during three months, reorganization of the lesions was reduced in comparison to the controls and an intense bacteriological activity persisted.

Animals↗
PubMed1975

[Endocrine cells of the gastric mucous membrane].

In order to obtain an additional information concerning a possible functional role of the main types of the endocrine cells (EC and ECL) on investigation of aspiration biopsy specimens taken from the middle third of the stomach in patients with ulcerative disease of the duodenum and chronic gastritis was carried out. Changes in morphology, distribution and number of the endocrine cells in pathology of the mucosa and in various acidity of the gastric juice were followed up. On the basis of the data obtained the conclusion is made that serotonin-producing (EC) cells seem to have nothing to do with the regulation of the activity of the fundal glands, whereas the enterochromaffin-like cells (ECL) influence the production of hydrochloric acid by pavement cells.

Chronic Disease↗
PubMed1979

[Results of cytological routine checks (author's transl)].

Reported in this paper are 1930 cytological routine smears taken from patients on the gynaecological ward. Findings included Pap. III eight times and Pap. IV in nine cases. Histological elucidation of all Pap. IV and the repeated Pap. III findings revealed the presence of six carcinomas in situ, two carcinomas of pavement epithelium, and two severe dysplasias. This shows that cytological routine checks can be meaningful and useful to the patients, even if undertaken in a small hospital.

Adult↗
PubMed1978

Surface features of exfoliated vaginal epithelial cells during the oestrous cycle of the rat examined by scanning electron microscopy.

The purpose of this study was to document vaginal exfoliative cytology (smears) as seen with the scanning electron microscope during the first, hormonally induced oestrous cycle of PMS-LH treated immature rats and to compare it with the surface morphology of the intact vaginal wall of similarly treated rats. Exfoliated cells were obtained by vaginal lavage 7--9 hours (pro-oestrus), 18--20 hours (oestrus), 28--34 hours (metoestrus) and 60--64 hours (dioestrus) after administration of luteinizing hormone. Cell suspensions were plated upon moistened Millipore filters according to the method of Shelton & Orenstein (1975). The pro-oestrous stage was characterized by round to ovoid cells with numerous short microvillus-like protrusions and blebs. The vaginal wall exhibited folds lined by cells with many short microvilli. Oestrus was characterized by flattened angular cells with either blebs, microridges or both. The intact wall exhibited 'flattened mosaics' of cells, some in the process of desquamation, with ridges and pits. Metoestrus resembled oestrus, except for the presence of a few leucocytes in the plated specimens. Dioestrus was characterized by an abundance of pleomorphic leucocytes with blebs of varying sizes. The vaginal wall appeared as a 'cobblestone' pavement with cells of varying sizes and shapes possessing numerous short, microvilli with bulbous endings.

Animals↗
PubMed1977

Establishment of epithelial cell lines from rat glandular stomachs.

Nine epithelial cell lines were isolated from glandular stomach cells of fetal and suckling JAR-2 rats after the elimination of mesenchymal cells by mechanical and colonial isolation methods. Those cells have been proliferating continuously in a typical pavement-like arrangement. In early cultures a part of focal monolayers of small epithelial cells died simultaneously ("contact death"). The cells of three lines (RGS-2,RGS-5 and RGS-8) formed hemicysts when incubated for several weeks without subcultivation. Addition of But2cAMP and theophilline into culture medium enhanced the hemicyst formation by RGS-8 cells. Some evidence suggested that those three lines were originated from mucous epithelium of rat glandular stomach. These epithelial cell lines would be useful in the study of chemical carcinogenesis in culture.

Animals↗
PubMed1977

Light and electron microscopy observations in the thyroid gland of the pheasant (Phasianus colchicus L.).

In the summer, the pheasant thyroid presents as a relatively quiescent organ with reduced secretory activity; the follicular epithelium is very low and mostly of the pavement type, while the follicles are unwontedly large and contain an increased amount of colloid. The follicular cell cytoplasm contains numerous characteristic spherical vacuolar structures. In the winter, however, the thyroid displays remarkable reconstruction and raised activity of the follicular cells, which are much higher and columnar; the small follicles contain less colloid. Peculiar rod-like or fusiform structures, some measuring up to 6,5 microgram, were observed in the cytoplasm of the follicular cells of both hen and cock pheasants in November and March. At the beginning of the winter (November), specific dark cells with pycnotic nuclei, evidently in process of degeneration, appeared in the follicular epithelium. In March, specific granulated cells (probably parafollicular cells) were found sporadically in the immediate vicinity of the wall of subcapsular follicles in cock pheasant.

Animals↗
PubMed1978

[Morphology and DNA content of cultures from normal and dysplastic epithelium, carcinoma in situ and carcinomas of the cervix uteri (author's transl)].

Morphology and DNA content were studied in explantate cultures of normal epithelium, persisting intraepithelial atypias (dysplasias and carcinomas in situ) and carcinomas of the cervix uteri. Intraepithelial atypias and carcinomas can be distinguished from the normal epithelium, growing strictly as a monolayer, chiefly by the primary and secondary loosening of the cellular lawn with increased tendency towards overlapping of cells. DNA determinations provide the possibility of demonstrating, also in vitro, deviations of the DNA content of dysplasias, carcinomas in situ and pavement epithelial carcinomas from the normal epithelium. The findings are in accord with the results which we obtained by in vivo studies and underlinions.

Biopsy↗
PubMed1978

[Comparative histochemical characteristics of the secretion of superficial gastric epitheliocytes].

Comparative histological investigation of the gastric pavement epitheliocytes in a number of species (amphibia, reptile, birds, mammals, man including) has demonstrated that in amphibia, protective function of the stomach is connected with the presence of a certain neutral carbohydrate component in its secrete. In reptiles, the barrier function is performed by the neutral carbohydrate component and sialosaccharides, in birds, besides the carbohydrates mentioned, sulphosaccharides, as well. Histochemical properties of the mammal stomach as a barrier are determined by phylogenetically dependent peculiarities of food specialization.

Animals↗
PubMed1977

[Biomechanics of the jaw apparatus in the horn-shark (Heterodontus portusjacksoni = Heterodontus philippi)].

The constructional morphology of the jaw apparatus in the horn-shark Heterodontus has been investigated. The origines and insertions of the jaw muscles have been delimited and the lines of action were determined. The individual muscles have been weighed, in order to get on the basis of their masses an estimate of the forces which are exerted by the components of the jaw musculature. The mandibular joints, the occlusion of the jaws, morphological details of the upper and lower jaws as well as the "subodontium" have been subject to macroscopic and microscopic study. The joint between palatoquadrate and mandibular consists of a medial and a lateral compartment. Only hinge movements are possible. If the jaws are closed, the contacts between upper and lower jaws are confined to the large crushing teeth of only one or two tooth families. The teeth are fixed to the jaw cartilage by ligamentous structures. Three layers can be discerned histologically: The uppermost layer, beneath the bases of the teeth, is composed of the fibrae interdentales and of the fibrae subbasales. By these, the individual teeth are firmly connected to form a continuous pavement. - The middle layer is characterised by the great number of cell nuclei. - The fibre system which constitutes the lowermost layer is arranged according to its function. The subdental layer of fibrous tissue grows faster than the one adjacent to the jaws. Thus a particular growth structure is formed. - Two constructive principles are realised: 1. The biting forces or "loads", applied to one or two teeth, are split and distributed on all teeth of the same family which are lingual of the loaded one. 2. As in the thecodont mammals, the compressive biting (= occlusal) force is transformed into a tensile force by the tooth-fixing apparatus and by the shapes of the jaws and this is sustained by fibrous structures. Magnitude and directions of the stresses which appear in the upper and lower jaw during biting are compared with stress patterns evoked in consoles and in beams of technical constructions. The moments of resistence have been calculated for 9 or 8 cross sections, respectively, through the upper and the lower jaw. The forms of both jaws are comparable to a beam of equal strength on two supports, namely, bitten object and joints; while the load is represented by the muscular force. Where the bending moments are at a maximum, opposite to the muscle insertions, a strong ligamentous reinforcement of the perichondrium extends parallel to the tooth rows and fades out towards the joint and towards the symphysis. The strength properties of cartilage and of collagenous fibres in the species under consideration have been measured. The lines of action of the jaw muscles intersect in the area where the moments of resistence reach their maximum. The largest crushing teeth are located in this same section, so that the muscles exert most force on the teeth, while the joint is exposed to only moderate compression.

Animals↗