Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Subcutaneous Tissue”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed1993

On line continuous monitoring of subcutaneous tissue glucose is feasible by combining portable glucosensor with microdialysis.

A new method for continuous measurement of subcutaneous tissue glucose content is introduced: by combining the microdialysis technique with a wearable amperometric glucose sensor, a device for continuous glucose measurement in the subcutaneous tissue was obtained. This device was applied to healthy volunteers (n = 10) over the period of an oral glucose load and to type I diabetic patients (n = 10) under the conditions of daily life. Glucose profiles in both healthy and diabetic persons were followed in the subcutaneous tissue up to 27 hours. This technique will certainly open new perspectives of monitoring and treating diabetic patients.

Biosensing Techniques↗
PubMed1999

Subcutaneous tissue oxygen and carbon dioxide tensions during hyperbaric oxygenation: an experimental study in rats.

OBJECTIVE: To investigate the response of subcutaneous tissue oxygen (O2) and carbon dioxide (CO2) tensions to hyperbaric oxygenation. DESIGN: Experimental study. SETTING: University hospital, Finland. SUBJECTS: 10 Wistar rats. INTERVENTION: Subcutaneous tissue PO2 and PCO2 were directly measured with an implanted Silastic tube tonometer and capillary sampling technique while breathing air and exposed to hyperbaric oxygen (HBO) at 2.5 or 2.8 ATA pressure. Hyperbaric exposures were carried out in a large multiplace chamber pressurised with air. MAIN OUTCOME MEASURES: Subcutaneous tissue PO2 and PCO2. RESULTS: The mean subcutaneous PO2 rose from the baseline of 8 kPa (60 mmHg) to 16 kPa (112 mmHg) when rats breathed room air during pressurisation to 2.8 atm. When the rats breathed oxygen at 2.5 ATA the maximal mean tissue PO2 was four times higher than the mean starting value. During the HBO treatment at 2.8 ATA the tissue PO2 rose to a value about five times above baseline. The tissue PCO2 values almost doubled during the exposure to HBO at 2.5 ATA, probably because elimination of carbon dioxide was impaired. CONCLUSION: Measurements of tissue PO2 and PCO2 with an implanted Silastic tonometer and a capillary sampling technique can successfully be adapted to hyperbaric conditions. The method yielded reproducible results and is applicable to clinical use in hyperbaric medicine.

Animals↗
PubMed2004

Tissue response to a membrane of demineralized bovine cortical bone implanted in the subcutaneous tissue of rats.

The treatment of persistent bone defects has encouraged the search for proper techniques or bone substitutes. In Dentistry, a common problem in the treatment of periodontal bone defects is the growth of tissues within the lesion, such as the junctional epithelium, which impair regeneration of these tissues. Guided tissue regeneration (GTR), based on the separation of the tissues by means of membranes or barriers, was developed in an attempt to improve periodontal regeneration. The aim of this study was to histologically evaluate the tissue response to a membrane of demineralized bovine cortical bone implanted in the subcutaneous tissue of rats. The study periods were 1, 3, 7, 15, 30 and 60 days after implantation. Analysis of the histological sections demonstrated a moderate to intense inflammatory response at 1 and 3 days, moderate at 7 and 15 days, and almost absent at 30 and 60 days. Resorption of the membrane began 15 days after implantation, and at 60 days only remnants could be detected in some animals. We concluded that the demineralized bovine cortical bone membrane was well tolerated by the tissues and is completely resorbed after 30-60 days by mononuclear cells and multinucleated giant cells, which disappear upon completion of the process.

Absorbable Implants↗
PubMed1982

Absorption of NPH-insulin from subcutaneous tissue: a methodological study in pigs.

To elucidate the validity of the indirect method of following insulin absorption from the subcutaneous tissue, i.e. external counting of injected 125-I insulin, the disappearance of 125-I NPH insulin from subcutaneous tissue was measured by a biotelemetric method (external measurement of radioactivity) and by direct determination of radioactivity and insulin in subcutaneous tissue extracted one to 300 min. after injection of 8 units 125-I NPH porcine insulin, 5 mm beneath the surface of the skin in 6 anaesthesized pigs. Furthermore, the appearance of insulin in arterial plasma was measured after inhibiting the endogenous insulin secretion of the pigs by epinephrine and propanolol. The disappearance of radioactivity measured continuously for 5 hours was of first order kinetics with t1/2=462+/-36 min. (mean+/-S.E.M.). The half-life of the injected depot of radioactivity (t1/2) demonstrated a large intra- as well as interindividual variation as seen in diabetics. In tissue extracts a highly significant (2P less than 0.001) correlation was found between radioactivity and insulin (r=0.93), indicating the radioactivity to be representative of insulin. During gel chromatography on Sephadex G 50 M only one peak of radioactivity was seen in all tissue extracts. 300 min. after NPH-insulin injection, however, the specific radioactivity of insulin was significantly higher (2P less than 0.05) than in tissue extracts sampled one min. after NPH insulin injection, indicating a slight accumulation of non-immunoreactive insulin degradation products. A fair correlation (r=0.75, 2 P less than 0.05) was seen between the disappearance of externally measured radioactivity or insulin from tissue extracts and the appearance of insulin in plasma. It is concluded that the insulin absorption coefficient is a relevant and biologically sensible expression of insulin absorption.

Absorption↗
PubMed1994

Influence of the thickness of the skin and subcutaneous tissue covering the mastoid on bone-conduction thresholds obtained transcutaneously versus percutaneously.

Percutaneous and transcutaneous bone-conduction thresholds were obtained at 0.25, 0.5, 1, 2, and 4 kHz in 57 patients who were fitted with the Bone Anchored Hearing Aid (BAHA). Additionally, the thickness of the skin and subcutaneous tissue covering the mastoid was determined. No relation was found between the thickness of the skin and subcutaneous tissue, and the improvement in bone-conduction thresholds at any of the frequencies, i.e. thresholds obtained percutaneously minus transcutaneously. The improvement (or deterioration) in speech recognition with the BAHA in a subgroup of patients who had previously used a (conventional) transcutaneous bone-conduction hearing aid was not related to the thickness of the skin and subcutaneous tissue layers. Therefore, the thickness of the skin and subcutaneous tissue layers measured pre-operatively cannot be used as a predictor of successful fitting with a BAHA.

Adolescent↗
PubMed1990

The relative biological effectiveness of fractionated doses of fast neutrons (42 MeVd----Be) for normal tissues in the pig. II. Late effects on cutaneous and subcutaneous tissues.

The late effects of irradiation with single and fractionated doses of X rays (250 kV) and fast neutrons (42 MeVd----Bc), on the cutaneous and subcutaneous tissues of the pig, have been evaluated from measurements of changes in relative field length. These were determined at intervals of 26-104 weeks after irradiation. For fractionated irradiation with X rays the average fractions exponent, N, obtained from a log-log plot of iso-effect dose (ED50) against fraction number was 0.41. This was independent of the period of assessment, with no significant indication of a time factor. However, the exponent N did vary with the level of effect and was in the range 0.33-0.51. It was greatest for a greater than or equal to 10% reduction in relative field length. Assuming the validity of the linear quadratic model of cell survival, the alpha/beta ratio was 1.95 Gy. However, this model fitted the data less well for the least severe levels of damage, and for these the alpha/beta ratios were not significantly different from zero. Irradiation with fast neutrons showed a small effect of fractionation for doses given in greater than or equal to 6 fractions compared with a single dose. There was no significant increase in iso-effect dose when the dose was given in 30 fractions compared with 6 fractions. The relative biological effectiveness for late cutaneous and subcutaneous damage for the energy of fast neutrons used did not vary with the period of assessment, i.e. 26-52 weeks compared with 65-104 weeks, and was not significantly different from that previously obtained for ischaemic dermal necrosis, seen after higher doses, at 12-20 weeks after irradiation.

Animals↗
PubMed2001

[Effect of subcutaneous tissue trimming on the survival skin area of avulsion skin flap].

OBJECTIVE: To investigate the effect of subcutaneous tissue trimming on the survival skin area of avulsion skin flap. METHODS: Degloving injury was created in bilateral hind limbs of 7 pigs with avulsion injury machine, 4 cm x 10 cm avulsion skin flaps were elevated in degloving areas. Skin flaps in one side were replanted as control without any treatment. Subcutaneous tissue in the skin flaps of another side was partially excised and replanted by trimmed skin flaps. Survival skin flaps was calculated with computer at 7 days after operation. RESULTS: In the control group, the survival skin area was (40.41 +/- 9.23)%, while in the experimental group, the survival skin area was (60.90 +/- 15.26)%. There was significant difference between the two groups (P < 0.05). CONCLUSION: Trimming off subcutaneous tissue does improve the survival area of avulsion skin flap.

Anastomosis, Surgical↗
PubMed1982

[Soft tissue reaction following bioactive and bio-inactive implantation materials in subcutaneous tissue of rats].

The investigation of bioactive materials in the subcutaneous tissue of the rat is a method of the biocompatibility testing of newly developed bio-vitrokerame. The histological assessment of the course of wound healing was the base of the evaluation after a period of 40 days. An extensively concluded cellular reaction and the formation of a thin fibrous capsule can be judged positively with aluminium oxide ceramics and beta tricalcium phosphate. Bioactive materials of a determined combination can arise problems.

Animals↗
PubMed1982

Time, dose and fractionation factor as an indicator of fibrosis of the abdominopelvic subcutaneous tissue.

Ninety-six patients treated with irradiation for epidermoid carcinoma of the uterine cervix were evaluated for the occurrence of subcutaneous tissue fibrosis of the hypogastrium. They were retrospectively stratified according to time, dose and fractionation (TDF) factors of the subcutaneous tissue, total dose delivered and treatment techniques. In our study only the TDF value of the subcutaneous tissue was unequivocally related to the occurrence of fibrosis. The numerical value of the TDF was found to be 110, above which 88.2% of the patients displayed fibrosis.

Abdomen↗
PubMed2006

Estimation of the viscous properties of skin and subcutaneous tissue in uniaxial stress relaxation tests.

Knowledge of viscoelastic properties of soft tissues is essential for the finite element modelling of the stress/strain distributions in finger-pad during vibratory loading, which is important in exploring the mechanism of hand-arm vibration syndrome. In conventional procedures, skin and subcutaneous tissue have to be separated for testing the viscoelastic properties. In this study, a novel method has been proposed to simultaneously determine the viscoelastic properties of skin and subcutaneous tissue in uniaxial stress relaxation tests. A mathematical approach has been derived to obtain the creep and relaxation characteristics of skin and subcutaneous tissue using uniaxial stress relaxation data of skin/subcutaneous composite specimens. The micro-structures of collagen fiber networks in the soft tissue, which underline the tissue mechanical characteristics, will be intact in the proposed method. Therefore, the viscoelastic properties of soft tissues obtained using the proposed method would be more physiologically relevant than those obtained using the conventional method. The proposed approach has been utilized to measure the viscoelastic properties of soft tissues of pig. The relaxation curves of pig skin and subcutaneous tissue obtained in the current study agree well with those in literature. Using the proposed approach, reliable material properties of soft tissues can be obtained in a cost- and time-efficient manner, which simultaneously improves the physiological relevance.

Animals↗
PubMed1996

Subcutaneous tissue involvement by T-cell lymphoma. A report of 2 cases.

BACKGROUND: T-cell lymphomas may involve the subcutaneous tissue as a manifestation of generalized disease. However, T-cell lymphomas rarely present with extensive involvement of the subcutaneous fat without other sites of disease. OBSERVATIONS: We describe 2 women who presented with fever and subcutaneous nodules or masses. In case 1, the nodules were generalized and did not respond to chemotherapy. The patient died 2 months after diagnosis. In case 2, the mass was large but localized and responded to chemotherapy. The tumor subsequently recurred in a cervical lymph node 9 months later, and the patient was being treated with chemotherapy 15 months after initial diagnosis. Histologically, biopsy specimens from both patients revealed malignant lymphoma involving the subcutaneous tissue. The dermis and epidermis were not involved. At low power the lesions resembled panniculitis, but high-power examination revealed cytologic atypia of the malignant lymphoid cells. Immunohistochemical studies revealed T-cell lineage. In case 2, the neoplastic cells also expressed the CD30 antigen, were positive for Epstein-Barr virus RNA, and carried the t(2;5) (p23;q35) chromosomal translocation. We interpreted case 1 as an example of subcutaneous panniculitic T-cell lymphoma. We believe that case 2 is best classified as anaplastic large cell lymphoma of T-cell lineage. CONCLUSIONS: A variety of T-cell lymphomas rarely present with only subcutaneous tissue involvement. Knowledge of this phenomenon and recognition of the cytologic atypia of the lymphoid cells will help to prevent misdiagnosis.

Adult↗
PubMed1979

Subcutaneous tissue gas space pressure during superficial isobaric counterdiffusion.

Changes in subcutaneous tissue pressure caused by N2O-He, 1-ATA isobaric counterdiffusion gas phase development were measured. Only the ears of New Zealand White rabbits were subjected to counterdiffusion. The rabbits breathed a mixture of 80% N2O-20% O2 while their ears alone were surrounded by He and the rest of their bodies continued to be surrounded by air. Subcutaneous pressure changes were transmitted to the transducer-recorded system via a fluid-filled subcutaneous needle. When the gas phase developed in subcutaneous tissue, pressure rose and a maximum pressure (Pmax) was reached. Pmax in the counterdiffused ear was 48 +/- 10 (SD) Torr, and mean time to reach Pmax was 75 +/- 10 (SD) min. The findings are discussed in relation to the pathological processes of isobaric inert gas counterdiffusion.

Animals↗
PubMed1975

The effect of induced arterial hypertension upon regional blood flow in subcutaneous tissue in patients with arterial insufficiency of the legs.

In nine patients with arterial insufficiency of the legs, the effect of induced arterial hypertension upon blood flow in subcutaneous tissue was correlated to the changes of blood flow in subcutaneous tissue during dependency. Arterial pressure was increased by constant intravenous infusion of angiotensin. Blood flow in subcutaneous tissue was measured 10 cm distal to the head of fibula, at the lateral malleolus, and at the base of the first toe by means of the xenon washout technique. It was found that in areas where blood flow decreased during dependency, blood flow decreased during angiotensin infusion. An increase in blood flow during angiotensin infusion was seen in areas where blood flow increased during dependency. It is concluded that the effect of angiotensin infusion on blood flow and of therapeutically induced hypertension can be predicted from the effect of orthostatic changes on blood flow. The results obtained support the hypothesis that the vessels behave as passive channels (i.e. blood flow depends mainly upon arterial perfusion pressure) in areas where the normal vasoconstrictor response to increased transmural pressure is abolished.

Angiotensin II↗
PubMed1994

Effect of Pasteurella haemolytica infection on alpha 1-acid glycoprotein and albumin concentrations in serum and subcutaneous tissue chamber fluid of calves.

Thermoplastic tissue chambers were implanted subcutaneously in the paralumbar fossae of 10 calves. Concentrations of alpha 1-acid glycoprotein (AAG) and albumin in serum and subcutaneous tissue chamber fluid were measured before and after inoculation of Pasteurella haemolytica into tissue chambers. Two months after implantation, serum and tissue chamber fluid samples were collected and all tissue chambers were then inoculated with P haemolytica. Additional serum and chamber fluid samples were collected two, four, six and 10 days after inoculation. The concentrations of AAG and albumin in the samples were measured by radial immunodiffusion assay and the bromcresol method, respectively. P haemolytica inoculation resulted in an increase in the serum and chamber fluid AAG concentrations and an increase in chamber fluid albumin concentrations, suggesting that the proportion of drugs bound to serum and interstitial proteins may be affected by P haemolytica infection.

Animals↗
PubMed1993

Experimental study on alkaline skin injuries--periodic changes in subcutaneous tissue pH and the effects exerted by washing.

A skin alkaline injury model was constructed using rats and 2N-NaOH. The changes over time, paying special attention to subcutaneous tissue pH, were recorded and included a comparative study of the effect on subcutaneous tissue pH of washing with water at 1, 10 and 30 min after injury. After inflicting alkaline injury, the subcutaneous tissue pH reached its peak value at the 32nd minute and had not recovered to the pre-experimental level by the 90th minute. The peak pH values of the 1-, 10- and 30-min delays before washing groups were 7.97, 10.57 and 12.17, respectively. When washing was started within 1 min of injury the tissue pH values did not exceed 8.00. Washing had virtually no effect on lowering the raised pH levels when the delay between injury and the start of washing was 10 and 30 min.

Animals↗
PubMed1999

Application of microdialysis for the determination of muscle and subcutaneous tissue concentrations after oral and topical ibuprofen administration.

BACKGROUND: The topical administration of non-steroidal antiinflammatory drugs (NSAIDs) is widely used for the treatment of soft tissue pain. However, it is not known whether effective tissue concentrations are reached with the topical route. OBJECTIVE: To evaluate and compare unbound muscle and subcutaneous tissue ibuprofen concentrations with use of microdialysis after topical and oral administration. METHODS: In a 2-way crossover design, 11 healthy volunteers received either 800 mg oral ibuprofen or 16 g of 5% ibuprofen gel applied onto the skin of the thigh (defined area, 17 x 19 cm). Microdialysis catheters were inserted into the medial vastus muscle (25 to 30 mm) and into the subcutaneous adipose layer of the thigh (4 to 5 mm). Dialysate was collected in 20-minute intervals up to 5 hours. RESULTS: Essentially all of the orally administered dose was recovered in urine as ibuprofen or metabolites during 24 hours, but only about 0.55% of the topically administered dose was recovered. The relative systemic bioavailability of ibuprofen gel, based on urine recovery data, was (mean +/- SD) 0.57%+/-0.30%. Mean values of the dialysate areas under the drug concentration-time curves after topical and oral administration were 731.2+/-605.0 and 176.6+/-122.9 ng x h x mL(-1) for subcutaneous tissue and 63.5+/-90.3 and 213.4+/-117.2 ng x h x mL(-1) for muscle, respectively. Muscle dialysate concentrations after topical administration varied considerably among the subjects. CONCLUSION: These results suggest that, if target tissue concentrations correlate directly with the degree of pain relief, patients with pain caused by dermal or subcutaneous tissue damage will have greater pain relief after topical administration of ibuprofen accompanied with less systemic side effects. In addition, a proportion of patients with muscle pain may also experience pain relief from topical ibuprofen.

Administration, Cutaneous↗
PubMed1975

Removal of exogenous triglycerides in human forearm muscle and subcutaneous tissue.

The removal of exogenous triglyceride (TG) in forearm muscle and subcutaneous tissue of 7 healthy male volunteers has been studied by nephelometric determinations of arterial-deep venous (a-dv) and arterial-superficial venous (a-sv) differences in concentration of fat particles. Exogenous TG was administered as a constant i.v. infusion of Intralipid over a period of 30 min at reat and another 15 min during forearm work. At rest a significant positive a-dv difference in fat particle concentration of 121 plus pr minus 21 mumol TG/l (mean plus or minus S.E.M.) was found, which correspondens to a fractional extraction of 1093 plus or minus 2.0%. Also the a-sv difference was significant, 81 plus or minus 14 mumol TG/l, 5.7 plus or minus 0.8% of the arterial concentration. During exercise no further significant removal was found. Thus both skeletal muscle and subcutaneous tissue seem to be able to remove exogenous TG in substantial amounts under resting conditions. In the exercising muscle, however, the direct removal of exogenous TG does not seem to be of significant importance.

Adult↗