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101.
Osteocyte Apoptosis and Osteoclast Presence in Chicken Radii 0–4 Days Following Osteotomy 总被引:2,自引:0,他引:2
Clark WD Smith EL Linn KA Paul-Murphy JR Muir P Cook ME 《Calcified tissue international》2005,77(5):327-336
Osteocyte apoptosis caused by load-induced microdamage is followed by osteoclastic bone remodeling, and a causal link between
apoptosis and repair has been suggested. The objectives of the present study were to use a chick model to examine the incidence
of osteocyte apoptosis and the presence of osteoclasts during the first 96 hours following an osteotomy, prior to extensive
callus mineralization. Osteotomies were performed on the right radii of 24 chicks at 23–24 days of age. The left radii served
as controls. Radii were collected and processed at six time points following surgery (0, 12, 24, 48, 72, and 96 hours). Decalcified
bone tissue sections were stained either for apoptosis using a modified TUNEL procedure or for tartrate-resistant acid phosphatase
to identify osteoclasts in the intracortical and periosteal envelopes. The percentage of apoptotic osteocytes, as well as
osteoclast counts (n/mm or n/mm2) were quantified in four regions (0–1, 1–2, 2–4, and 4–8 mm from the site of the osteotomy; regions 1–4, respectively) in
the osteotomized radii and in the same measured areas in the control radii. Data for osteocyte apoptosis and osteoclasts in
the control limb were subtracted from the osteotomized limb data to identify differences due to surgical influence. The incidence
of osteocyte apoptosis was significantly higher at 12, 24, 48, and 72 hours versus 0 hours following osteotomy, and the response
was highest in region 1; however, there was no interaction between time and region. Intracortical osteoclast counts (n/mm2) were elevated after 48 hours, and the response was similar in all regions. The data demonstrate that osteocyte apoptosis
occurs within 24 hours in response to an osteotomy and temporally precedes an increase in osteoclast presence. Hence, osteocyte
apoptosis may play a role in signaling during the bone healing process. 相似文献
102.
Neovascularization in prefabricated flaps using a tissue expander and an implanted arteriovenous pedicle 总被引:6,自引:0,他引:6
Creating prefabricated flaps using tissue expanders in combination with the implantation of maximal blood flow vascular pedicles into suitable tissue areas represents a new tendency in the reconstruction of large skin defects. In 42 Chinchilla Bastard female rabbits weighing 3,700-4,600 g, skeletonized arteriovenous pedicles with maximal blood flow, dissected from the femoral and saphena magna bundles, were implanted underneath abdominal fasciocutaneous flaps. Oval tissue expanders of 250 ml were placed and fixed on the abdominal wall to expand these prefabricated flaps. The evaluation parameters were macroscopic observation, blood analysis, selective microangiography, histology, and scintigraphy. The study results showed that neovascularization in expanded prefabricated flaps was established from newly formed vessels generated from the implanted pedicles and their vascular connections with the originally available vasculature in the flap. After 20 days of prefabrication, the entirety of the expanded prefabricated flaps was perfused by blood flow supplied from newly implanted arteriovenous pedicles. The study indicated that an expanded prefabricated flap can be successfully created by the simultaneous implantation of a maximal blood flow pedicle in combination with flap expansion. 相似文献
103.
Surgical epicardial left ventricular lead versus coronary sinus lead placement in biventricular pacing. 总被引:8,自引:0,他引:8
Helmut Mair Joerg Sachweh Bart Meuris Georg Nollert Michael Schmoeckel Albert Schuetz Bruno Reichart Sabine Daebritz 《European journal of cardio-thoracic surgery》2005,27(2):235-242
OBJECTIVE: Biventricular pacing has demonstrated improvement in cardiac function in treating congestive heart failure (CHF). Two different operative strategies (coronary sinus vs. epicardial stimulation) for left ventricular (LV) pacing were compared. METHODS: Since April 1999, a total of 86 patients (pts, age: 63+/-10 years) with depressed systolic LV function (mean ejection fraction 24+/-9%), left bundle-branch-block (mean QRS 182+/-22 ms) and congestive heart failure NYHA III or higher were enrolled. For biventricular stimulation coronary sinus (CS) leads were placed in 79 pts. Nine of these devices were converted to surgical epicardial LV-leads, because of CS-lead failure. In 7 patients epicardial LV-leads were initially implanted surgically, accounting for a total of 16 pts with surgical placed epicardial steroid-eluting LV-leads. For these, a limited left-lateral thoracotomy (7+/-4 cm) was used. Thirty-three (38%) pts had an indication for a defibrillator. The mean follow-up time was 16.4+/-15.4 months (0.1-45 months), representing 107.1 patient-years. RESULTS: In the biventricular pacing mode, QRS duration decreased to 143+/-16 ms (P<0.001). Threshold capture of the CS-leads increased significantly compared to surgically placed epicardial leads (18 month control: 2.2+/-1.4V/0.5 ms vs. 0.7+/-0.3V/0.5 ms), which had no increase in threshold (P<0.001). At the 18 month follow-up 7 CS-leads had a threshold of >4V/0.5 ms vs. epicardial leads which were under 1.1V/0.5 ms, except for one (1.8V/0.5 ms). After CS-lead implantation 25 LV-lead related complications occurred, (failed implantation, CS-dissection, loss of pacing capture, diaphragm stimulation or lead dislodgment), vs. one dislodgement after surgical epicardial lead placement (P<0.05). Correct lead positioning (obtuse marginal branch area) was achieved in all surgical epicardial placements but only in 70% with CS-leads (P<0.03). In the follow up period, 9 pts died (4 cardiac related). Heart transplantation was necessary in 4 pts due to deterioration of the cardiomyopathy. CONCLUSIONS: Surgical epicardial lead placement revealed excellent long-term results and a lower LV-related complication rate compared to CS-leads. Although, the approach via limited thoracotomy for biventricular pacing is associated with 'more surgery', it is a safe and reliable technique and should be considered as an equal alternative. 相似文献
104.
Rosiglitazone improves glomerular hyperfiltration, renal endothelial dysfunction, and microalbuminuria of incipient diabetic nephropathy in patients 总被引:31,自引:0,他引:31
Microalbuminuria, an early feature of diabetic nephropathy, indicates intrarenal endothelial damage. In type 2 diabetes, microalbuminuria is strongly related to insulin resistance. We therefore investigated whether rosiglitazone, an insulin-sensitizing drug that is known to improve endothelial dysfunction, was able to improve intrarenal endothelial dysfunction and microalbuminuria. Nineteen type 2 diabetic patients participated in this double-blind cross-over trial. Nine patients with newly diagnosed disease without microalbuminuria were randomized to a treatment with rosiglitazone or nateglinide, each for 12 weeks. Ten patients with microalbuminuria were randomized to rosiglitazone or placebo, each for 12 weeks in addition to their previous antidiabetic medication. After each treatment, glomerular filtration rate (GFR), renal plasma flow, and filtration fraction were measured before and after blockade of nitric oxide (NO) by intravenous administration of N-monomethyl-L-arginine-acetate (L-NMMA). Ten healthy subjects served as control subjects. Type 2 diabetic patients at baseline showed glomerular hyperfiltration compared with healthy control subjects. Rosiglitazone reduced elevated GFR and filtration fraction toward control primarily in patients with microalbuminuria (GFR: 133.4 +/- 9.8 vs. 119.6 +/- 8.7 ml/min; filtration fraction: 23.2 +/- 1.7 vs. 20.5 +/- 1.6% before and after rosiglitazone, respectively; control subjects: GFR 111.7 +/- 8.6 ml/min, filtration fraction 20.4 +/- 1.5%). Rosiglitazone improved intrarenal NO bioavailability in type 2 diabetes toward control as shown by infusion of L-NMMA. Rosiglitazone reduced albumin excretion in type 2 diabetes with microalbuminuria from 116.5 +/- 31 to 40.4 +/- 12 mg/day. Rosiglitazone ameliorated glomerular hyperfiltration in early type 2 diabetes, improved NO bioavailability, and lessened renal end-organ damage in type 2 diabetes with microalbuminuria. 相似文献
105.
106.
Experimental brain tumours were produced in adult cats by stereotactic xenotransplantation of the rat glioma clone F98. Regional ATP, glucose and lactate were measured after 2-4 weeks on coronal cryostat sections by substrate-induced bioluminescence, potassium content was imaged by the histochemical sodium cobaltinitrite method, and regional pH by incubating cryostat sections with the fluorescent pH-indicator umbelliferone. The regional biochemical alterations were correlated with magnetic resonance imaging and tissue water content. Biochemical changes were heterogeneous in tumours but exhibited a rather uniform pattern in peritumoural oedema. ATP was consistently reduced, glucose and lactate were increased and pH was more alkaline than in normal white matter. The decrease of ATP matched the increase of water, indicating that ATP decline represents fractional dilution in the oedematous tissue rather than break-down of energy metabolism. The increased lactate levels, therefore, may originate from the tumour and not from a metabolic disturbance in the peritumoural oedematous tissue. The implications of this interpretation for the pathogenesis of peritumoural oedema are discussed. 相似文献
107.
Biophysical, histological and biochemical changes after non-ablative treatments with the 595 and 1320 nm lasers: a comparative study 总被引:1,自引:0,他引:1
Dang Y Ren Q Hoecker S Liu H Ma J Zhang J 《Photodermatology, photoimmunology & photomedicine》2005,21(4):204-209
BACKGROUND/PURPOSE: The objective was to compare the efficiencies of the 595 nm pulsed dye and the 1320 nm Nd : YAG laser non-ablative rejuvenation. METHODS: KM mice were irradiated with the 595 nm pulsed dye and the 1320 nm Nd : YAG lasers. Histological changes were evaluated immediately, 1, 7, 21, 30 and 60 days after the two laser treatments. Skin hydration and hydroxyproline content were measured to quantify the degree of improvement of the skin's water-holding capacity and the rate of hydroxyproline synthesis. RESULTS: Although not statistically significant, the 1320 nm Nd : YAG laser treatment induced 9.7% greater improvement of skin hydration than the 595 nm laser while the 595 nm pulsed dye laser treatment led to a thicker dermis and 8.7% greater increase of hydroxyproline than the 1320 nm laser. More than 50% increase of collagen type I was observed in 75% of 595 nm laser-treated sites and 42% of 1320 nm laser-treated sites, and more than 25% increase of collagen type III was observed in 75% of 595 nm laser-treated sites and 50% of 1320 nm laser-treated sites. The 595 nm laser treatment was better in increasing the amount of collagen fibers, especially collagen type I (P < 0.05). CONCLUSION: Our results demonstrated that the 595 nm laser appeared to be more effective in increasing new collagen formation, while the 1320 nm laser was superior to the 595 nm laser in improving the skin's water-holding capacity. 相似文献
108.
'Specific' cutaneous infiltrate of B-cell chronic lymphocytic leukemia at the site of a florid herpes simplex infection 总被引:1,自引:0,他引:1
Background: Specific cutaneous infiltrates in patients with leukemia generally carry a grim prognosis. However, non-neoplastic skin diseases may be associated with recruitment of normal and neoplastic leukocytes circulating in the peripheral blood. In those instances, neoplastic cells may be detected in skin lesions without an adverse effect on prognosis. Methods: In a patient with B-cell chronic lymphocytic leukemia, a specific infiltrate developed at the site of a florid herpes simplex infection. Clinically, the lesion presented itself as an ulcerated tumor. Results: Histopathologically, the lesion was characterized by a dense, diffuse infiltrate of small hyperchromatic lymphocytes throughout the entire dermis. Lymphocytes showed an aberrant CD20(+)/CD43(+)/CD5(+) phenotype of neoplastic B cells, and monoclonal rearrangement of immunoglobulin gamma genes could be demonstrated by polymerase chain reaction. Although criteria for leukemia cutis were fulfilled, the patient did well. Conclusions: The cutaneous infiltrate of neoplastic cells seemed to be part of a physiologic response to the antigenic stimulus, rather than indicating an exacerbation of leukemia. Ziemer M, Bornkessel A, Hahnfeld S, Weyers W. 'Specific' cutaneous infiltrate of B-cell chronic lymphocytic leukemia at the site of a florid herpes simplex infection. 相似文献
109.
Isabelle Le Fur Sabine Lopez Frédérique Morizot Christiane Guinot Erwin Tschachler 《Skin research and technology》1999,5(3):182-188
Background/aims: Understanding structural and functional differences between facial areas is necessary for the formulation of cosmetics and dermatological preparations well tailored to the skin's biophysical characteristics. The objective of the present study was to compare biophysical parameters on malar and frontal facial areas of healthy women classified according to self-reported cosmetic skin types.
Methods: The study population comprised 253 women aged from 20 to 50 years who did not display any signs of dermatological disease. Women declared spontaneously their cosmetic skin type. Skin capacitance, sebum casual level, skin temperature, transepidermal water loss (TEWL), skin colour and relief were assessed on cheeks and forehead in a controlled environment.
Results: All biophysical parameters showed statistically significant differences between the two zones. Mean a* chromametric values and TEWL values were significantly higher on cheeks. In contrast, mean b * chromametric values and sebum casual levels showed the highest values on the forehead. Moreover, skin capacitance, temperature, roughness and L .* chromametric value showed minor, while statistically significant, differences between the two zones. With marginal exceptions, the differences between the facial zones for each biophysical parameter remained statistically significant, irrespective of self-reported skin type.
Conclusion: Biophysical parameter mean values differ between frontal and malar zones regardless of self-reported skin type. Except for the elevated sebum casual levels in greasy and combined skin, no single or combined biophysical characteristics could be linked to any of the self-reported skin types. Furthermore our data confirm that in contrast to the common belief that dry skin is associated with reduced sebum production, sebum levels in women declaring to have dry skin and those declaring to have normal skin were not found to be different. 相似文献
Methods: The study population comprised 253 women aged from 20 to 50 years who did not display any signs of dermatological disease. Women declared spontaneously their cosmetic skin type. Skin capacitance, sebum casual level, skin temperature, transepidermal water loss (TEWL), skin colour and relief were assessed on cheeks and forehead in a controlled environment.
Results: All biophysical parameters showed statistically significant differences between the two zones. Mean a* chromametric values and TEWL values were significantly higher on cheeks. In contrast, mean b * chromametric values and sebum casual levels showed the highest values on the forehead. Moreover, skin capacitance, temperature, roughness and L .* chromametric value showed minor, while statistically significant, differences between the two zones. With marginal exceptions, the differences between the facial zones for each biophysical parameter remained statistically significant, irrespective of self-reported skin type.
Conclusion: Biophysical parameter mean values differ between frontal and malar zones regardless of self-reported skin type. Except for the elevated sebum casual levels in greasy and combined skin, no single or combined biophysical characteristics could be linked to any of the self-reported skin types. Furthermore our data confirm that in contrast to the common belief that dry skin is associated with reduced sebum production, sebum levels in women declaring to have dry skin and those declaring to have normal skin were not found to be different. 相似文献
110.