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PubMed2002

Appendiceal stump abscess as an early complication of laparoscopic appendectomy: report of a case.

We report the case of an appendiceal stump abscess that was treated by relaparoscopy 4 days after a laparoscopic appendectomy (LA). Surgeons should be aware of the possibility of appendiceal stump abscess occurring as an early complication of LA. When performing LA, the appendiceal stump should be as short as possible, and the ligation of the root of the appendix should be only moderately tight, so as not to cause ischemic change of the stump, indicated by discoloration or edema. The insertion of a drain for monitoring exudate, as well as sonography, and relaparoscopy are helpful for diagnosing and treating this complication.

Abdominal Abscess↗

PubMed1979

Economy of Photosynthate Use in Nitrogen-fixing Legume Nodules: Observations on Two Contrasting Symbioses.

The economy of C use by root nodules was examined in two symbioses, Vigna unguiculata (L.) Walp. (cv. Caloona):Rhizobium CB756 and Lupinus albus L. (cv. Ultra):Rhizobium WU425 over a 2-week period in early vegetative growth. Plants were grown in minus N water culture with cuvettes attached to the nodulated zone of their primary roots for collection of evolved CO(2) and H(2). Increments in total plant N and in C and N of nodules, and C:N weight ratios of xylem and phloem exudates were studied by periodic sampling from the plant populations. Itemized budgets were constructed for the partitioning and utilization of C in the two species. For each milligram N fixed and assimilated by the cowpea association, 1.54 +/- 0.26 (standard error) milligrams C as CO(2) and negligible H(2) were evolved and 3.11 milligrams of translocated C utilized by the nodules. Comparable values for nodules of the lupin association were 3.64 +/- 0.28 milligrams C as CO(2), 0.22 +/- 0.05 milligrams H(2), and 6.58 milligrams C. More efficient use of C by cowpea nodules was due to a lesser requirement of C for synthesis of exported N compounds, a smaller allocation of C to nodule dry matter, and a lower evolution of CO(2). The activity of phosphoenolpyruvate carboxylase in nodule extracts and the rate of (14)CO(2) fixation by detached nodules were greater for the cowpea symbiosis (0.56 +/- 0.06 and 0.22 milligrams C as CO(2) fixed per gram fresh weight per hour, respectively) than for the lupin 0.06 +/- 0.02 and 0.01 milligrams C as CO(2) fixed per gram fresh weight per hour. The significance of the data was discussed in relation to current information on theoretical costs of nitrogenase functioning and associated nodule processes.

Journal Article↗

PubMed1966

Studies on the effect of experimental nonketotic diabetes mellitus on antibacterial defense. I. Demonstration of a defect in phagocytosis.

Chronically diabetic nonketotic rats were shown to be more susceptible to experimental Type 25 pneumococcal pneumonia than nondiabetic rats. The cumulative mortality in the diabetic group was significantly higher at infecting doses of 10(3), 10(4), 10(5), and 10(6) organisms, and the LD(50) was less than one twentieth of that for the nondiabetic group. More than ten times as many viable pneumococci were found in the pneumonic lesions of the diabetic animals at 24 and 36 hr as were present in the lesions of the nondiabetic controls, and serial histologic studies revealed that phagocytosis was strikingly depressed in the alveolar exudates of the diabetic animals. The diabetic state was also found to cause a similar depression of in vivo phagocytosis in preformed peritoneal exudates. The results of in vitro experiments indicated that the principal defect in the diabetic animals resided in their serum rather than in their polymorphonuclear leukocytes. The depressive factor in the serum was identified as the abnormally high concentration of glucose. Since equivalent molar concentrations of unmetabolized sugars added to normal serum caused a similar depression of phagocytosis, it was tentatively concluded that the action of the glucose on the leukocytes was primarily osmotic. The sensitivity of the granulocytes to the glucose effect, however, depended upon the conditions of the phagocytic test. Only when the pneumococci were encapsulated and the leukocytes derived from inflammatory exudates were crowded together, as in vivo, was the depressive action of the glucose clearly demonstrable.

Animals↗

PubMed1989

Intact soil-core microcosms for evaluating the fate and ecological impact of the release of genetically engineered microorganisms.

Intact soil-core microcosms were studied to determine their applicability for evaluating the transport, survival, and potential ecosystem effects of genetically engineered microorganisms before they are released into the environment. Soil-core microcosms were planted with wheat and maize seeds and inoculated with Azospirillum lipoferum SpBr17 and SpRG20a Tn5 mutants, respectively. Microcosm leachate, rhizosphere soil, plant endorhizosphere, insects, and xylem exudate were sampled for A. lipoferum Tn5 mutant populations. A. lipoferum Tn5 populations, determined by most-probable-number technique-DNA hybridization, varied from below detection to 10 g of dry root in the rhizosphere, with smaller populations detected in the endorhizosphere. Intact soil-core microcosms were found to maintain some of the complexities of the natural ecosystem and should be particularly useful for initial evaluations of the fate of plant-associated genetically engineered bacteria.

Journal Article↗

PubMed1996

Bioactive constituents of Chinese natural medicines. II. Rhodiolae radix. (1). Chemical structures and antiallergic activity of rhodiocyanosides A and B from the underground part of Rhodiola quadrifida (Pall.) Fisch. et Mey. (Crassulaceae).

Two bioactive cyanoglycosides, rhodiocyanosides A and B, and two oligoglycosides, rhodioflavonoside [gossypetin 7-O-beta-D-glucopyranosyl(1-->3)-alpha-L-rhamnopyranoside] and rhodiooctanoside [octyl alpha-L-arabinopyranosyl(1-->6) beta- D-glucopyranoside), were isolated from the Chinese natural medicine "Si Lie Hong Jing Tian" (Shiretsukoukeiten in Japanese), the underground part of Rhodiola quadrifida (Pall.) Fisch. et Mey., together with four known compounds: rhodioloside, n-hexyl beta-D-glucopyranoside, gossypetin 7-O-alpha-L-rhamnopyranoside, and tricetin. The chemical structures of new glycosides were determined on the basis of chemical and physicochemical evidence. Rhodiocyanosides A and B exhibited inhibitory activity on the histamine release from rat peritoneal exudate cells sensitized with anti-2,4-dinitrophenyl IgE. Additionally, rhodiocyanoside A, the major constituent of this natural medicine, was also found to show antiallergic activity in a passive cutaneous anaphylaxis test in rat.

Animals↗

PubMed2001

Mini-dental implant insertion with the auto-advance technique for ongoing applications.

The clinical and histological results of two cases demonstrating retrieved Sendax mini-dental implants in two different patients is the focus of this report. The mini-dental implants were inserted using the auto-advance technique and loaded immediately. The implants were retrieved at 4 months following insertion and at 5 months following insertion and were prepared and reviewed histologically. Clinically, the implants had no mobility, with no apparent exudate or bleeding upon probing, prior to removal. At the time explant procedures were performed, the mini-dental implants had provided immediate support for prostheses during the integration of traditional root-form endosteal implants. Upon explantation, the mini-dental implants were in a state of health and functioning in their intended purpose. Histologically, the bone appeared to be integrated to the surface of the implant at the light microscope level, and the bone appeared to be relatively mature and healthy in the areas observed, more so than one would expect in this amount of time from insertion of mini-dental implants with immediate loading. A discussion of the purposes and technique used for insertion and removal of these mini-dental implants is discussed. This is the first human histological report on the auto-advance technique with immediate loading of mini-dental implants, demonstrating feasibility in ongoing applications.

Aged↗

PubMed2004

Non-surgical management of a chronic periapical lesion associated with traumatised maxillary central incisors: case report.

A case is reported of a chronic periapical lesion involving maxillary central incisors with a history of traumatic injury eight years previously and subsequent development of a painful swelling that occasionally caused partial blockage of the nasal cavities. Retrograde surgery for removal of the suspected cystic lesion was scheduled. As a temporary measure before surgery, the necrotic pulp exudate was removed through standard endodontic access cavities prepared on the palatal surfaces of the crowns of the two central incisors, and a calcium hydroxide paste dressing material was placed inside the root canals up to the apices. The calcium hydroxide dressing was changed every four weeks and the case was followed up until healing of the periapical lesion occurred. The surgical procedure was postponed and finally cancelled when complete healing became evident in recall radiographs.

Adult↗

PubMed1992

Two critical confounding factors in periodontal epidemiology.

The prevalence and severity of periodontitis is considerably lower than was previously estimated. The available epidemiological methods are based on the premise that loss of periodontal attachment is a unique sign of periodontitis. However, additional factors resulting in loss of periodontal attachment confound data obtained from modern studies. The physiological process of continuous tooth eruption results in loss of periodontal attachment over a lifetime, at an approximate rate of 0.1 mm/year. Anthropological and clinical evidence for continuous tooth eruption is reviewed. The position of the alveolar crest appears to be stable; loss of periodontal attachment occurs as the teeth erupt and less of the root is embedded in bone. Retrograde periodontitis caused by pulpal disease is a known cause of severe, localised destruction of periodontal tissues. Its signs and symptoms include periodontal pocket formation, purulent inflammatory exudates, angular bone loss, swelling and bleeding of the gingival tissues and increased tooth mobility. Anthropological, experimental and clinical evidence for retrograde periodontitis is discussed. Misdiagnosis of angular (hemiseptal), furcal and other forms of localised periodontal damage as periodontitis has probably resulted because of the inability to determine the quality of pulpal health and the assumption of a gingivitis-periodontitis continuum. New epidemiological methods need to be developed in which physiological and all pathological conditions which affect the periodontal attachment are recognised and appropriately categorised.

Confounding Factors, Epidemiologic↗

PubMed2007

Autoimmune properties of nucleus pulposus: an experimental study in pigs.

STUDY DESIGN: Assessment of activated T and B cells in a subcutaneous chamber filled with autologous nucleus pulposus using flow cytometry and immunohistochemistry. OBJECTIVES: To examine if subcutaneously placed autologous nucleus pulposus may attract activated T and B cells in an animal model. SUMMARY OF BACKGROUND DATA: Nucleus pulposus has been suggested to trigger an autoimmune response if exposed to the immune system, for example, in association with disc herniation. T-cell activation represents a hallmark in the generation of an autoimmune response, subsequently leading to the differentiation of B cells, but a causal association between the exposure of nucleus pulposus to the systemic circulation and T and B cell activation is still lacking. METHODS: Autologous nucleus pulposus was harvested from the intervertebral disc of 9 pigs and placed subcutaneously in perforated titanium chambers. In order to control for the effect of the titanium chamber, an additional empty chamber was placed subcutaneously in each pig. After 7 days, the pigs were killed and the chambers were harvested. Flow cytometry and immunohistochemistry were used for analysis of T-helper cells (CD4+), cytotoxic T cells (CD8+), and B cells (Igkappa) in the chamber exudates and T cells (CD45RC) in the remaining blood clot tissue of the chamber. RESULTS: As compared with the empty chambers, the proportion of activated T cells (CD4+ and CD8+) was significantly higher in the exudate of the nucleus pulposus filled chamber. The proportion of activated B cells expressing immunoglobulin kappa (Igkappa) was also significantly elevated in the exudate of the nucleus pulposus chambers. The analysis of the remaining chamber tissue revealed a significantly higher amount of T cells (CD45RC) in the nucleus pulposus chambers than in the empty chambers. CONCLUSIONS: The present findings indicate that nucleus pulposus attracts activated T and B cells. However, since the cell population in the nucleus pulposus of young pigs may differ from that of adult humans, the obtained data may not be directly transferred to the human situation of a disc herniation. The observations in the present study may nevertheless explain some of the local tissue reactions occurring in association with disc herniation and nerve root involvement, thereby providing further insight into the pathophysiology of sciatica.

Animals↗

PubMed1978

Cation pretreatment effects on nitrate uptake, xylem exudate, and malate levels in wheat seedlings.

Week-old wheat seedlings absorbed at least 40% NO(3) (-) from NaNO(3) when preloaded with K(+) than when preloaded with Na(+) or Ca(2+). Cultures of Triticum vulgare L. cv. Arthur were grown for 5 days on 0.2 mm CaSO(4), pretreated for 48 hours with either 1 mm CaSO(4), K(2)SO(4), or Na(2)SO(4), and then transferred to 1 mm NaNO(3). All solutions contained 0.2 mm CaSO(4). Shoots of K(+)-preloaded plants accumulated three times more NO(3) (-) than shoots of the other two treatments. Initially, the K(+)-preloaded plants contained 10-fold more malate than either Na(+)- or Ca(2+)-preloaded seedlings. During the 48-hour treatment with NaNO(3), malate in both roots and shoots of the K(+)-preloaded seedlings decreased. Seedlings preloaded with K(+) reduced 25% more NO(3) (-) than those preloaded with either Na(+) or Ca(2+). These experiments indicate that K(+) enhanced NO(3) (-) uptake and reduction even though the absorption of K(+) and NO(3) (-) were separated in time. Xylem exudate of K(+)-pretreated plants contained roughly equivalent concentrations of K(+) and NO(3) (-), but exudate from Na(+) and Ca(2+)-pretreated plants contained two to four times more NO(3) (-) than K(+). Therefore K(+) is not an obligatory counterion for NO(3) (-) transport in xylem.

Journal Article↗

PubMed2005

A link between citrate and proton release by proteoid roots of white lupin (Lupinus albus L.) grown under phosphorus-deficient conditions?

White lupin (Lupinus albus L.) is able to acclimate to phosphorus deficiency by forming proteoid roots that release a large amount of citric acid, resulting in the mobilization of sparingly soluble soil phosphate in the rhizosphere. The mechanisms responsible for the release of organic acids have not been fully elucidated. In this study, we focused on the link between citrate and malate release and the release of H+ and other inorganic ions by proteoid roots of white lupin. The release of citrate was closely correlated with the release of H+, K+, Na+ and Mg2+, but not with that of Ca2+. The stoichiometric relationships between citrate release and the release of H+, K+, Na+ and Mg2+ were 1 : 1.3, 1 : 2.1, 1 : 1.5 and 1 : 0.47, respectively. Similar correlations were found between exudation of malate and cations. During 30 min incubation, fusicoccin addition stimulated H+ and malate release, but not citrate release. A concomitant stimulation of H+, malate and citrate release was measured after 60 min incubation. Vanadate inhibited the release of H+ and malate, but not that of citrate. Anthracene-9-carboxylic acid, an anion channel blocker, caused a concomitant decrease in release of citrate, malate and H+. We conclude that for export of citrate across the plasma membrane of proteoid root cells, H+ release is not strictly related to citrate release. Other cations such as K+ and Na+ can also serve as counterions for citrate release. In contrast, malate release shows a strong H+ release dependency.

Anions↗

PubMedDate not supplied

Antiinflammatory evaluation of a Pluchea indica root extract.

A methanolic fraction of a chloroform extract of defatted Pluchea indica roots was investigated for its antiinflammatory potential against several models of inflammation. The extract showed significant inhibitory activity against carrageenin-, histamine-, serotonin-, hyaluronidase- and sodium urate-induced pedal inflammation. The extract inhibited protein exudation and leucocyte migration. The extract also inhibited carrageenin- and cotton pellet-induced granuloma formation as well as turpentine-induced joint oedema and adjuvant-induced polyarthritis. The present observations establish the efficacy of the extract in the exudative, proliferative and chronic stages of inflammation.

Adrenalectomy↗

PubMed1995

Periodontal tissue regeneration on the surface of synthetic hydroxyapatite implanted into root surface.

Several studies have demonstrated that periodontal ligament (PDL)-derived cells can form a new connective tissue attachment (NCTA) not only on denuded dentin but also on nondental inorganic materials. Although the cellular response to these materials may be different than that to denuded dentin, the process of NCTA formation on the surface of non-dental inorganic materials is still undetermined. In the present study, we compared the process of NCTA formation on the surface of an inorganic material with that on a denuded root surface by implanting a block of synthetic hydroxyapatite (HA) into a root cavity prepared on the first molar of a rat. We then observed tissue regeneration under conditions where the PDL-derived cells could populate the HA surface using an occlusive membrane. After fibrinous exudation at 3 days postoperatively, granulation tissue from the PDL filled the space between the HA block and the membrane at 1 week. Four weeks after the operation, although the granulation tissue increased in density at the interface to the HA block, no obvious deposition of cementum-like tissue was seen on the HA block. Six weeks after the operation, the deposition of cementum was observed on the surface of the HA block. The deposition of cementum became more extensive and insertion of collagen fibers into the cementum layer became more obvious 8 weeks postoperatively. Twelve weeks after the operation, the cementum covered almost the entire surface of the HA block. On the surface of the denuded dentin in control teeth, cementum deposition was seen at 4 weeks after the operation and increased in thickness from 6 weeks on.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1998

Origin and gender determination of dried blood on a statue of the Virgin Mary.

In Italy, blood exudation from objects of worship recurs frequently in ancient chronicles and literature, in popular beliefs, and even in modern mass-media reports. This phenomenon, that was associated with epochal or catastrophic events, has roots that reach classical antiquity. In the last few years, several events connected with the detection of bloody "tears" on statues of the Virgin Mary required forensic medicine investigations. In the present report we describe genetic investigations conducted on dried blood of unknown derivation found on a statuette representing the Virgin Mary. To test the human or animal origin of the blood, we amplified Alu-specific sequences from DNAs obtained from the unknown sample and from humans, large apes, various Old and New World monkeys, a prosimian, mouse, common domestic artiodactyls and chicken. This investigation restricted the range of possible origin of the statue blood to humans, apes and Old World monkeys. To test the male or female origin of the blood, we used a multiplex nested polymerase chain reaction method, that allows the simultaneous amplification of the X-specific locus DXZ4 and of the Y-specific locus SRY. Considering the unlikelihood of an origin from simian Old World primates, the exclusive amplification of the X-specific product from the unknown sample and from human female blood controls, compared to the amplification of distinct X- and Y-specific bands from human male blood controls, strongly supports a human female origin of the statue blood.

Animals↗

PubMed1998

[Adhesive lumbar arachnoiditis].

Spinal arachnoiditis, an inflammatory process involving all three meningeal layers as well as the nerve roots, is a cause of persistent symptoms in 6% to 16% of postoperative patients. Although spinal surgery is the most common antecedent associated with arachnoiditis, multiple causes have been reported, including infection, intrathecal steroids or anesthetic agents, trauma, subarachnoid hemorrhage and ionic myelographic contrast material--both oil soluble and water soluble. In the past, oil-based intrathecal contrast agents (Pantopaque) were associated with arachnoiditis especially when this material was introduced into the thecal sac and mixed with blood. Arachnoiditis is apparently rarely idiopathic. The pathogenesis of spinal arachnoiditis is similar to the repair process of serous membranes, such as the peritoneum, with a negligible inflammatory cellular exudate and a prominent fibrinous exudate. Chronic adhesive arachnoiditis of the lower spine is a myelographic diagnosis. The myelographic findings of arachnoiditis were divided into two types by Jorgensen et al. In type 1, "the empty thecal sac" appearance, there is homogeneous filling of the thecal sac with either absence of or defects involving nerve root sleeve filling. In type 2 arachnoiditis, there are localized or diffuse filling defects within the contrast column. MRI has demonstrated a sensitivity of 92% and a specificity of 100% in the diagnosis of arachnoiditis. The appearance of arachnoiditis on MRI can be assigned to three main groups. The MRI findings in group I are a conglomeration of adherent roots positioned centrally in the thecal sac. Patients in group II show roots peripherally adherent to the meninges--the so called empty sac. MRI findings in group III are a soft tissue mass within the subarachnoid space. It corresponds to the type 2 categorization defined by Jorgensen et al, where as the MRI imaging types I and II correspond to the myelographic type 1.

Arachnoiditis↗

PubMed1987

The survival of adult mouse sensory neurons in vitro is enhanced by natural and synthetic substrata, particularly fibronectin.

Primary cultures derived from adult mouse dorsal root ganglia have been maintained in the presence or absence of 5 X 10(-6)M cytosine arabinoside for periods of up to 4 weeks. In cultures in which cytosine arabinoside is present, the non-neuronal cell population is effectively reduced. When uncoated plastic substrata are used there is also a concurrent decrease in the number of neurons if the medium is supplemented with cytosine arabinoside. The effects on neuron survival of substrata coated with fibronectin, polyornithine, polylysine, and exudates prepared from mouse liver cells were studied. It was shown that neuronal densities similar to those with uninhibited media may be retained in the presence of cytosine arabinoside if fibronectin-coated substrata are prepared. With the other coating agents neuronal survival was also enhanced but to a lesser extent. The study offers a means therefore of producing purer cultures of dorsal root ganglia neurons than has previously been possible from adult mammalian sources.

Animals↗

PubMed2003

Ectomycorrhizas of Cortinarius helodes and Gyrodon monticola with Alnus acuminata from Argentina.

Field ectomycorrhizas of Cortinarius helodes Moser, Matheny & Daniele (sp. nov) and Gyrodon monticola Sing. on Alnus acuminata Kunth (Andean alder, aliso del cerro) are described based on morphological and anatomical features. Ectomycorrhizal roots were sampled beneath fruitbodies of C. helodes and G. monticola from two homogeneous A. acuminata forest sites located in Tucuman and Catamarca Provinces in Argentina. C. helodes ectomycorrhizas showed a thick white to beige mantle exuding a milky juice when injured, were bluish toward the apex, and had hyphal strands in the mantle. G. monticola ectomycorrhizas showed some conspicuous features like highly differentiated rhizomorphs, inflated brown cells on the mantle surface, and hyaline and brown emanating hyphae with dolipores. Restriction fragment length polymorphism analysis of the nuclear rDNA internal transcribed spacer provided a distinctive profile for each of the collections of fruitbodies and the mycorrhizal morphotypes.

Agaricales↗

PubMed1978

Allantoin and Allantoic Acid in the Nitrogen Economy of the Cowpea (Vigna unguiculata [L.] Walp.).

The ureides, allantoin and allantoic acid, represented major fractions of the soluble nitrogen pool of nodulated plants of cowpea (Vigna unguiculata [L.] Walp. cv. Caloona) throughout vegetative and reproductive growth. Stem and petioles were the principal sites of ureide accumulation, especially in early fruiting.Labeling studies using (14)CO(2) and (15)N(2) and incubation periods of 25 to 245 minutes indicated that synthesis of allantoin and allantoic acid in root nodules involved currently delivered photosynthate and recently fixed N, and that the ureides were exported from nodule to shoot via the xylem. From 60 to 80% of xylem-borne N consisted of ureides; the remainder was glutamine, asparagine, and amino acids. Allantoin predominated in the soluble N fraction of nodules and fruits, allantoin and allantoic acid were present in approximately equal proportions in xylem exudate, stems, and petioles.Extracts of the plant tissue fraction of nitrogen-fixing cowpea nodules contained glutamate synthase (EC 2.6.1.53) and glutamine synthetase (EC 6.3.1.2), but little activity of glutamate dehydrogenase (EC 1.4.1.3). High levels of uricase (EC 1.7.3.3) and allantoinase (EC 3.5.2.5) were also detected. Allantoinase but little uricase was found in extracts of leaflets, pods, and seeds.Balance sheets were constructed for production, storage, and utilization of ureide N during growth. Virtually all (average 92%) of the ureides exported from roots was metabolized on entering the shoot, the compounds being presumably used as N sources for protein synthesis.

Journal Article↗