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At least 19 recordsLinked to original sources
PubMed1977

Changes within vascular bundles of rodent kidneys caused by different diets.

Morphological effects caused by two different diets (low protein-high water intake, and high protein-restricted water) on the vascular bundles in the outer medullary zone of the kidney were studied in the laboratory white mouse and in the golden spiny mouse (Acomys russatus, Muridae). In both rodents, when on a low protein-high water intake diet, considerable interstitial substance was found between the vasa recta of the bundles. No interstitial substance was found in animals on high protein-low water intake diet; as a result the vasa recta of the vascular bundle adhered closely. The low protein-high water intake diet caused a marked diuresis, low urine osmolality and low urinary urea concentration. It is assumed that the increase in interstitial substance between the vasa recta of the vascular bundle lowers the efficiency of the counter current barrier system for urea in the kidney and, as a consequence, the medullary urea gradient and urine concentrating capacity decreases. In animals on a high protein diet, the closely juxtaposed vasa recta assure an efficient countercurrent exchange, leading to accumulation and maintenance of a large urea gradient in the medulla and maximal urine concentration. It is suggested that the amount of interstitial material between the vasa recta of the vascular bundle might serve as a modulating factor for the urea concentration in the kidney.

Animal Nutritional Physiological Phenomena↗
PubMed2026

Zea mays Drought-Overly Sensitive1/TUBA4 Is Wilty3, and Transcriptome Co-Expression Analysis of Shoot Meristem Mutant Tissues Reveals Wilty2/TUB6:Wi3 Interactions Associated With Stem Vascular Bundle Development.

Plant vasculature is essential for the transport of water, nutrients, and signaling molecules across organs, while also providing critical mechanical support for growth and development. Disruptions in vascular bundle formation can therefore lead to severe physiological and developmental defects. In maize, ethyl methanesulfonate (EMS)-induced dominant nonallelic Wilty mutants exhibit a pronounced wilting phenotype even under well-watered conditions, indicating underlying defects in vascular function. In this study, we characterized the Wi3 mutant, identified as ZmDrought-Overly-Sensitive1/DOS1, and compared it with the previously described Wi2 mutant to uncover shared mechanisms underlying their phenotypes. We provide evidence, by bulk segregant resequencing linkage disequilibrium of SNPs adjacent to the causal Wilty SNPs in respective ß- and α-tubulin genes, for the personal communication from Gerry Neuffer that Wi2/ß-tub6 provenance is from ACR-related stock, whereas Wi3/α-tub4 allele is from Mo17, not B73 as claimed by the authors who cloned Dos1. Histochemical staining and Fourier-transform infrared (FTIR) spectroscopy of vascular bundles in Wi3 indicated apparent alterations in cellulose and lignin content consistent with those observed in Wi2. Transcriptome analysis of shoot meristems further indicated that similar sets of genes and pathways are differentially expressed in both mutants, suggesting convergence on common biological pathways. Using bulk-segregant whole-genome resequencing, we identified alpha-tubulin4 (TUA4) as the causal gene in Wi3 (ZmDOS1), harboring a C-to-T substitution within the N-terminal GTPase-binding domain. This mutation results in a glutamic acid196-to-lysine substitution. Given that α- and β-tubulin subunits heterodimerize, and in many plants and animal mutant alleles are dominant-negative gains-of-function, we infer Wi2, Wi3, and likely Wi4, based on very similar FTIR biophysical difference spectra, may act as effectors of vascular bundle cell wall deposition, potentially involving vesicle trafficking as recently shown for asymmetric cell divisions in maize stomatal development. Together, these findings highlight the functional interdependence of tubulin subunits and provide a plausible mechanistic framework for the striking biophysical, transcriptomic, and phenotypic similarities observed between Wi2, Wi3/ZmDOS1, and Wi4 mutants.

bulk segregant analysis↗
PubMed1976

[Injuries of the thigh bone with a destruction of the neuro-vascular bundle].

From 1969 to 1971 the authors treated 1360 injured patients, eight of which suffered serious injuries of the thigh; fractured femur complicated by a severed Femoral Popliteal Artery, and lesions of the Sciatic Nerve. Six patients were injured at work, one in an automobile accident, and one was a gunshot victim. In approximately 1000 fractures one is complicated by an injured neurovascular bundle. The clinical picture of such a case is characteristic. The arteriograph is used only to locate the lesion. Reconstruction of the artery must be accomplished some eight to twelve hours following the injury. In all of the authors' cases, this was done one to eight hours following the trauma. After twelve hours, ischemic necrosis of the soft tissue (musculature) sets in requiring amputation. The remaining segment of the damaged artery is usually resected. In one case, a segment 8 cm. long was removed. Following the termino-terminal anastomosis, the injured extremity was placed in a flexed position whlich alleviated the tension on the sutures. The result of vein autographs are worse than those of the termino-terminal anastomoses. Thrombosis later begins to restrict blood flow through the reconstructed artery, but by this time, adequate collateral circulation has been established. The limb has thus been saved. Heparin is administrated immediately before and during the operation in a dosage of 5000 units per 500 ml. of physiological solution. Postoperatively, it is not used as it acts on the fibrin thrombi, and not on the thrombocyte thrombi which are formed postoperatively in the areas where the tunica intima has been damaged. Heparin is indicated in the prophylaxis of venous thrombosis. In these cases in which the femur was fractured, the question asked is whether to perform the osteosynthesis and anastomosis simultaneously, or to perform the former at a later time. The authors chose both methods for various reasons. Only a few cases permitted the authors to decide which approach would be better. Usually they performed a temporary fixation of the bone with Rusch's Pin, and sutured the artery. Four months later, a compressive osteosynthesis using an L-plate, was performed. In four cases, the Sciatic Nerve was injured, which, according to the circumstances was sutured either immediately, or 3 to 4 weeks later. In 3 patients, good functional results were obtained. Three cases resulted in a contracture of the knee, two of which also had residual Sciatic Paresis. One case resulted in permanent venous stasis (edema of the legs, and two cases results in amputation.

Adult↗
PubMedDate not supplied

Urinary concentrating processes in vertebrates.

Avian and mammalian kidneys can produce a urine hyperosmotic to the blood by means of a renal countercurrent system. Birds are uricotelic; mammals are ureotelic. It is proposed that the inner medulla present in mammalian, but not in avian kidneys serves specifically to accumulate urea in the inner and outer medulla. Among mammalian kidneys the degree to which urea accumulates in the inner medulla is inversely related to the complexity of the vascular bundles (in the outer medulla) and the cortical urea recycling index. A model is proposed for urea recycling via the vascular bundles. The renal pelvis varies in size among mammals. Its relative size is unrelated to the type of vascular bundles, cortical recycling index; or urea accumulation in the inner medulla. Since urine refluxes into the renal pelvis during rising urine flow only, the function of the pelvis could be that of bringing the more dilute urine into contact with the outer medulla and underlying capillaries, thereby aiding in reducing the urea concentration in outer and inner medulla during rising urine flow. The size of the renal pelvis may be related to the volume of the inner medulla. Other factors may also be involved.

Animals↗
PubMed1979

Blood vessel transplantation to bone.

In dogs an artery, a vein, and a vascular bundle were transplanted into intact bone, isolated bone segments, necrotized bone, and homografts of bone. Active proliferation of new blood vessels and formation of new bone occurred in all instances where the vascular bundle was used, when the vein was implanted into the intact bone and isolated bone, and only when the artery was implanted into intact bone. As a result of these experiments, vascular bundle transplantation has been performed in patients with Kienboeck's disease, and avascular necrosis of the scaphoid, the femoral head, the talus, and other conditions.

Adult↗
PubMed1979

Visualization of intrarenal catecholamine-containing elements: fluorescence histochemistry and electron microscopy.

Fluorescence histochemistry and electron microscopy were used to study catecholamine-containing elements in rat and cat kidneys. There were fluorescent nerve plexuses associated with the arterial system of the renal cortex from which nerves extended into the medulla forming dense networks in the vascular bundles of the outer part of the medulla. Also, there were small cells found singly and in clusters which emitted the blue fluorescence characteristic of catecholamine-containing cells. These cells were associated with the periarterial nerve plexuses and were frequently encountered in the cat medullary vascular bundles. Electron microscopy of the cat renal medulla revealed processes with the structure of typical adrenergic terminals and other processes that resemble small intensely fluorescent (SIF) cell processes.

Adrenergic Fibers↗
PubMed1977

Comparison of vegetative anatomy of piperales. I. Juvenile xylem of twigs.

Medullary bundles of Piperaceae resemble those of Ranunculaceae. The nature of tracheary elements of primary xylem suggests that Houttuynia cordata (Saururaceae), Piper cubeba (Piperaceae) and Chloranthus officinalis (Chloranthaceae) are of lower evolutionary status than others. Among these three, P. cubeba shows stratification of secondary xylem, a specialized character. Lateral wall of metaxylem tracheary elements and distribution of bundles of Peperomia, suggest their primitive status and distinctness, supporting separation of "Peperomiacea:" (of NOVAK). Piper cubeba, Houttuynia and Chloranthus bear one important Ranunculaceous character: scalariform perforation in primary vessels. Primitive species of Peperomia carry probably another Ranunculaceous character, i.e., many circles of medullary bundles. Shape and pattern of vascular bundles of Piper cubeba, Houttuynia and Chloranthus are similar. Other species of Piper show modifications. Peperomia represents another distinct pattern.

Plants↗
PubMedDate not supplied

[Comparative angioarchitectonics of the kidneys of several rodents].

Studies have been made on kidney angioarchitectonics in 3 rodent species (allied taxonomically, but significantly different in their habitat) - the albino rat, the gerbil Meriones erythrourus and the aquatic rodent must-rat Ondatra zibetica - after the injection of the vessels with India ink and subsequent microphotometric analysis of unstained sections. The general pattern of vascular system of the kideny is similar in all the species studied. However, significant differences were found in vascularisation of the cortex and especially of the outer and inner medulla. In M. erythrourus, vascularisation of the papilla is approximately 2 1/2 times more intense than that of the cortex; large vascular bundles in the outer medulla are separated from both interbundle plexus and vascular system of the papilla; the glomeruli differ in their size; arterial sphincters are more numerous in the cortex. In O. zibetica, vascularisation of the papilla is somewhat 3 times less intense as compared to that of the cortex; medullar bundles are diffuse; the structure of the glomeruli is more uniform. With respect to its kidney angioarchitectonics, the albino rat occupies intermediate position. The observed differences are discussed in relation to ecological specialization of the species studied, indicating the important role of vascular system of the kidney in the formation of concentrating capacity of the latter.

Animals↗
PubMed1979

[An experimental study on repair and restoration of gliding function of the injured flexor tendon of the finger. Part 6: A mode of vascularization of the grafted tendon within the pseudosheath (author's transl)].

The so-called two-stage procedure has been used in the reconstructive surgery for the severely injured flexor tendon of the finger. However, only little has been known as to vascularity of the grafted tendon within the pseudosheath. In order to clarify this problem, a series of experimental studies were carried out using young chickens. First, the flexor tendon of the fourth digit of chicken with its sheath was replaced by a silicone rod. The distal end of the rod was sutured to the stump of the flexor digitorum profundus and the proximal end left free. Then, in ten to sixteen weeks, upon removal of the rod, the flexor digitorum profundus of the third digit was grafted through into the newly formed pseudosheath. The paw was immobilized with plaster case in moderate flexion for three weeks, then the chicken was allowed to walk freely. At the different time intervals, starting from the third day to the fifteen weeks after surgery, a mode of vascularization of the grafted tendon and its surrounding tissue was examined microangiographically. The vessels appear at the area of proximal and distal stump of the grafted tendon a week postoperatively, and additional vessels appear at the contact area of the pseudosheath and the grafted tendon two weeks postoperatively. These vessels formed mutual anastomosis in five to six weeks. With time, the vessels connecting between the epitenon and the pseudosheath gradually enlarge and assemble together to form vascular bundles, so that the appearance of the structure becomes similar to that of the mesotenon. Three weeks postoperatively, the vessels appeared in the grafted tendon, and grew gradually so that these vessels ran through the full length of the grafted tendon in five to six weeks. About ten weeks, the vascularity of the grafted tendon is more abundant than that of the normal tendon, but diminished gradually so as to resemble that of the normal tendon at the fifteeth week. Thus, the growth of the vessels of the tendon grafted by two-stage procedure is delayed by two weeks compared with that by the primary tendon grafting.

Animals↗
PubMed1979

A new island flap transfer from the dorsum of the index to the thumb.

We describe here a new island flap from the dorsum of the index finger, transferred on the first dorsal metacarpal artery with one or two veins and the terminal branches of the radial nerve. This vascular bundle is a reliable one, for we have had no necrosis in 12 consecutive cases. The quality of its venous outflow and the use of a dorsal donor site give it advantages over the Moberg-Littler island flap, unless a dorsal vein from the latter flap is preserved and sutured to a vein in the recipient site. The arterial vascularization without any skin pedicle makes this "kite" flap a more practical one than the "flag" flaps of Vilain or Holevitch or Kuhn. Finally, a one-stage transfer is usually preferable to a two-stage one (e.g. Adamson, Braillar). In a single operation, this transfer provides composite resurfacing of the thumb while bringing in new blood and nerve supply.

Bone Transplantation↗
PubMed1977

Measurements on the kidneys and vasa recta of various mammals in relation to urine concentrating capacity.

Maximum urine-concentrating capacity (UCC) differs widely among mammals of different species, being very high in some desert species (e.g. kangaroo rats) and very low in freshwater acquatic species (e.g. beaver). In this study, kidneys of 21 species of mammals from widely different habitats were studied in histological sections to determine whether differences in UCC can be attributed to differences in kidney structure. Parameters studied included the ratio of medullary to cortical thickness, the proportional subdivision of the medulla into inner and outer zones, and the dimensions of the vasa recta expressed in terms of the total area and the number of lumens within the vascular bundles. Determinations were made at a level where the size of individual vasa recta bundles has reached a constant maximum size, i.e. in the distal half of the outer zone. A positive correlation was found between the UCC and the ratio of medullary length to cortical thickness. No clear correlation existed between the proportion of the medullary length comprised of outer or inner zones and the UCC, although a trend to higher UCC in animals with relatively longer inner zones was apparent. Thus, it appears that the relative length of the entire medullary region is a major factor determining UCC, but the length of individual medullary zones is of lesser importance. A correlation was also found between the density of vasa recta per cubic millimeter of medullary tissue (the number of lumens regardless of identify in bundles, based on the number counted at the level sampled) and the UCC of the species. Data reported here support the view that UCC can be correlated with two parameters of kidney structure - the length of medulla relative to that of cortex and the density of vasa recta within the outer zone. It is proposed that the anatomical characteristics of the vascular supply to the medulla - that is, the vasa recta - are equally as important for the concentration of urine as is the primary mechanism determined by the characteristics of the loop of Henle and collecting ducts.

Anatomy, Comparative↗
PubMed1978

The cytochemical localization of nucleotide pyrophosphatase activity in plant tissues using naphthyl esters of thymidine-5'-phosphate.

A cytochemical method for the localization of nucleotide pyrophosphatase activity in plants employing naphthol AS-BI thymidine 5'-monophosphate and alpha-naphthyl thymidine 5'-monophosphate as specific substrates is reported. Biochemical evidence for the validity of this method is presented and the synthesis of the naphthol AS-BI ester is described. The application of this cytochemical technique to shoots of Triticum sp. and roots of Vicia faba has shown nucleotide pyrophosphatase to be ubiquitous in its distribution in these organs and to occur in a structurally-bound form in the cytoplasm. The highest activity was detected in developing fibres adjacent to the leaf vascular bundles, in the coleoptile epidermal and hypodermal cells and in the coleoptile and leaf xylem.

Chemical Phenomena↗
PubMed1979

The neuro vascular flap in finger tip injuries.

The Kutler technique to restore skin cover in finger tip injuries was modified by mobilising the lateral triangular flap completely on its neuro-vascular bundle. Resultant increased mobility permitted greater advancement of the flap to allow adequate cover of the denuded finger tip. A unilateral flap is often sufficient.

Adolescent↗
PubMed1978

Localization of vicilin peptidohydrolase in the cotyledons of mung bean seedlings by immunofluorescence microscopy.

Vicilin peptidohydrolase, the protease that hydrolyzes the reserve proteins in the cotyledons of mung bean (Vigna radiata) seedlings, has been localized intracellularly by immunofluorescence microscopy using monospecific antibodies against the enzyme and rhodamine-coupled goat-anti-rabbit immunoglobulin G's. The enzyme can first be visualized after 3 days of seedling growth and is associated with small foci within the cytoplasm of the storage parenchyma cells farthest from the vascular bundles. On the 4th day of growth, the protease is also present in the numerous large protein bodies within these cells. Vicilin peptidohydrolase is known to be synthesized de novo starting on the 3rd day of growth. Our observations are therefore consistent with the interpretation that the enzyme is synthesized in the cytoplasm and subsequently transported to the protein bodies.

Cytoplasm↗
PubMed1977

The traumatic bone cyst.

A case is reported of traumatic cyst lying in the molar region of the mandible. It extended to the inferior border of the mandible and extended the buccal alveolar bone. The cystic cavity contained the inferior neuro-vascular bundle yellow serous fluid, and a small amount of gas. The wall of the cavity was lined with loosely arranged connective tissue with numerous capillaries. Healing was uneventful and clinical and radiographic examinations revealed restoration of bone structure and normal contours.

Adolescent↗
PubMed2026

The CsTBH-CsROP2 Module Regulates Waterlogging Tolerance via Auxin-Mediated Adventitious Root Formation in Cucumber.

Cucumber (Cucumis sativus L.) requires frequent irrigation due to its shallow root system and high transpiration rate of the aboveground parts. However, it is also prone to waterlogging damage. Therefore, understanding its response to waterlogging is crucial for breeding waterlogging-tolerant varieties. Although Rho of Plants GTPases play well-established roles in regulating development and stress signalling, their functions in plant adaptation to waterlogging stress has yet to be fully elucidated. Here, we identified nine CsROP genes in the cucumber genome, which exhibit evolutionary diversification but retain conserved functional domains. Functional analysis revealed that CsROP2 acts as a negative regulator of adventitious root formation. It modulates auxin accumulation in hypocotyl vascular bundles, thereby suppressing adventitious root development and enhancing waterlogging sensitivity. The HD-Zip I transcription factor CsTBH directly binds the CsROP2 promoter and activates its expression. Our study uncovers a CsTBH-CsROP2 module that governs adventitious rooting and waterlogging tolerance by modulating auxin homeostasis. These findings provide new insights into the crosstalk between developmental programmes and stress signalling pathways and offer potential genetic targets for improving stress resilience in cucumber and other crops.

CsROP2↗