scholarly journals Influence of Clarithromycin on Early Atherosclerotic Lesions after Chlamydia pneumoniae Infection in a Rabbit Model

2002 ◽  
Vol 46 (8) ◽  
pp. 2321-2326 ◽  
Author(s):  
Ignatius W. Fong ◽  
Brian Chiu ◽  
Esther Viira ◽  
Dan Jang ◽  
James B. Mahony

ABSTRACT Chlamydia pneumoniae may play a role in atherogenesis and vascular diseases, and antibiotics may prove useful in these conditions. Three groups of New Zealand White rabbits (24 per group) were infected via the nasopharynx with C. pneumoniae on three separate occasions (2 weeks apart). Group I was untreated and sacrificed at 12 weeks; group II received clarithromycin at 20 mg/kg/day for 8 days, beginning 5 days after each inoculation (early treatment); and group III received a similar dose of clarithromycin starting 2 weeks after the third inoculation and continued for 6 weeks thereafter (delayed treatment). To test for a possible anti-inflammatory effect of clarithromycin, two other groups of uninfected rabbits (12 animals in each) were fed 0.5% cholesterol-enriched chow, and one of these groups was treated with clarithromycin at 30 mg/kg/day for 6 weeks. Of 23 untreated infected rabbits, 8 developed early lesions of atherosclerosis, whereas 2 of the 24 early-treated group II had similar changes (P = 0.036 [75% efficacy]). However, in the delayed-treatment group, group III, 3 of 24 rabbits developed early lesions of atherosclerosis, thus demonstrating 62.5% reduction compared to the untreated controls (P = 0.07 [trend to statistical significance]). C. pneumoniae antigen was detected in 8 of 23 group I (untreated) rabbits versus 1 of 24 of the early-treated (group II) rabbits and 4 of 24 animals in the delayed group III (P = 0.009 and 0.138, respectively). All of the untreated, cholesterol-fed rabbits had moderate to advanced atherosclerosis (grade III or IV); clarithromycin had no effect on reducing the prevalence of but did reduce the extent of atherosclerosis in the cholesterol-fed rabbits by 17% compared to untreated controls. Thus, clarithromycin administration modified C. pneumoniae-induced atherosclerotic lesions and reduced the ability to detect organism in tissue. Early treatment was more effective than delayed treatment.

1999 ◽  
Vol 6 (6) ◽  
pp. 891-894 ◽  
Author(s):  
Ignatius W. Fong ◽  
Brian Chiu ◽  
Esther Viira ◽  
Dan Jang ◽  
Michael W. Fong ◽  
...  

ABSTRACT There is increasing data implicating Chlamydia pneumoniae in the pathogenesis of atherosclerosis, and antibiotics may theoretically be useful to prevent secondary vascular complications. Three groups of New Zealand White specific-pathogen-free rabbits, fed cholesterol-free chow, were inoculated via the nasopharynx on three occasions, 2 weeks apart, with C. pneumoniae. Group I (n = 23) rabbits were untreated; group II (n = 24) rabbits were treated with azithromycin at 30 mg/kg of body weight daily for 3 days and then once every 6 days, starting 5 days after first inoculation and continuing until sacrifice (early treatment); and group III (n = 24) rabbits were treated with the same dose of azithromycin but initiated 2 weeks after the last inoculation. All animals were sacrificed at 10 to 11 weeks after initial inoculation and examined for signs of atherosclerosis of the aorta. Eight (34.8%) untreated rabbits developed early signs of atherosclerosis, whereas only one (4.2%) in the early-treatment group had such signs (P = 0.02). However, eight rabbits (33.3%) of the delayed-treatment group had atherosclerotic changes of the aorta and no significant reduction compared to untreated rabbits. Early treatment of C. pneumoniae-infected rabbits with azithromycin was highly effective (87%) in preventing atherosclerotic changes, but delayed treatment was ineffective. It is possible that longer or more aggressive antibiotic treatment may be needed to reverse preformed lesions or that antibiotics may not be of value once lesions have formed.


2021 ◽  
Vol 9 (1) ◽  
pp. 76-81
Author(s):  
Aisha Azmat ◽  
Muhammad Ahmed

Background: Limited research studies are reported regarding the toxicological effect of different herbal medicine already used in different countries. Objective: This research study was planned to examine the changes in liver (biochemical and histological) associated with oral administration of somina (acute and sub-acute) in rats. Methodology: Group– I served as control (saline), while other groups (II, III) were daily treated with somina at different doses of 0.285g/kg (group – II), 10g/kg/day (group – III), for 14 (set I), 21 (set II), and 30 (set III) consecutive days.  Each group contains 12 rats. During the study period, signs and behavioral changes, mortality, were observed. At the end of study period, blood sample was drawn directly from heart, for the estimation of liver enzymes: Bilirubin (BIL), alkaline phosphatase (ALP), serum glutamic pyruvic transferase (SGPT), aspartate aminotransferase (SGOT), Albumin (ALB) and total protein (TP). The liver was carefully dichotomized, weighed, and further processed for histopathological analysis. Results: Herbal drug somina was claimed to be practically non-toxic as in rats no mortality was recorded after the oral administration of somina (14, 21 and 30 consecutive days). Liver profile showed non-significant changes in treated group- II and III (P > 0.05), as compared to the control (group- I). The histopathological examination did not reveal any deteriorative effect. Conclusion: It was concluded that oral administration of somina did not produce any significant detrimental effects on rat liver (biochemical and histopathological parameters), even at doses of 10g/kg/day indicating its safe use.


2005 ◽  
Vol 18 (4) ◽  
pp. 779-790 ◽  
Author(s):  
M. Migliori ◽  
L. Giovannini ◽  
V. Panichi ◽  
C. Filippi ◽  
D. Taccola ◽  
...  

In this study, we investigated the effect of 1,25(OH)2D3 on proteinuria and on the alteration of slit diaphragm-associated proteins induced by anti-Thy 1.1 in Wistar rats. Four groups of animals were studied: group I, anti-Thy 1.1 treated rats; group II, anti-Thy1.1 treated group that at day 2, after the onset of overt proteinuria, started the treatment with 1,25(OH)2D3; group III, normal control rats injected with vehicle alone; group IV, rats that received only 1,25(OH)2D3. At day 2, in group I and II, before the administration of 1,25(OH)2D3, protein excretion was significantly increased when compared to controls. Overt proteinuria was maintained until day 14 in group I whereas in group II protein excretion was significantly reduced from day 3 to day 14. Moreover, treatment with 1,25(OH)2D3 abrogated podocytes injury, detected as desmin expression and loss of nephrin and zonula occludens-1 (ZO-1), two slit diaphragm-associated proteins, and glomerular polyanion staining, that were observed in group I. In conclusion, these results suggest that 1,25(OH)2D3 administrated with a therapeutic regiment may revert proteinuria, counteracting glomerular podocyte injury.


Author(s):  
Waleed K. Ghanim ◽  
Nada N. Al-Shawi

Cyclophosphamide is chemotherapeutic agent that utilized for the treatment of different malignancies; however its’ used associated with numerous adverse effects. Vitamin B2 and vitamin B12 suggested having myeloprotective effect. This work is designed to investigate the myeloprotective effect of both vitamins against cyclophosphamide induced myelosuppression. One hundred adult rats of both sexes were used in this study. The animals were randomly enrolled into ten groups of 10 rats each. Group I: Control group. Group II: Cyclophosphamide-treated. Group III and Group IV Orally-administered vitamin B2 (10, and 40 mg/kg/day), respectively alone for 7 days. Group V: Orally-administered vitamin B12 (0.1 mg/kg/day) alone for 7 days. Group VI and Group VII: Orally-administered vitamin B2 (10, and 40 mg/kg/day), respectively for 7 days and a single IP injection of cyclophosphamide (150 mg/kg) at day 7.Group VIII: Orally-administered vitamin B12 (0.1 mg/kg/day) for 7 days and a single IP injection of cyclophosphamide (150 mg/kg) at day 7. Group IX: Orally-administered a combination of vitamin B2 (10 mg/kg/day) and vitamin B12 (0.1 mg/kg/day) for 7 days and a single IP injection of cyclophosphamide (150 mg/kg) at day 7. Group X: orally-administered a combination of vitamin B2 (40 mg/kg/day) and vitamin B12 (0.1 mg/kg/day) for 7 days and a single IP injection of cyclophosphamide (150 mg/kg) at day 7. On day eight, animals were sacrificed and blood collected for CBCs and femur bone were extracted for bone marrow histological examination. Vitamin B2 and vitamin B12 significantly (P<0.05) increase CBCs; and the combination of vitamins produce -a significant (P<0.05) increase in CBCs compared to corresponding counts in other Groups, and -improve histopathological changes compared to Group II rats. In conclusion both vitamins may have myeloprotective effects against cyclophosphamide-induced myelosuppression.


1992 ◽  
Vol 73 (4) ◽  
pp. 1510-1516 ◽  
Author(s):  
J. R. Thomas ◽  
J. M. Harlan ◽  
C. L. Rice ◽  
R. K. Winn

Two models of sepsis were investigated using rabbits. In the first model, rabbits given lipopolysaccharide (LPS) were treated with saline (group II) or CD18 monoclonal antibody (MAb) 60.3 (group III). Group I animals received no LPS. Cardiac output was maintained by infusion of lactated Ringer solution with group II (95 +/- 68 ml/kg) requiring significantly more than group I (0 +/- 0 ml/kg) or group III (39 +/- 27 ml/kg). Lung permeability indexes in groups II (median 0.002, range 0.023) and III (median 0.0035, range 0.053) were not different but were significantly greater than group I (median 0.0007, range 0.001). In the second model, peritonitis was produced by devascularizing the appendix, leaving it in situ for 19 h, and then performing an appendectomy. Saline or MAb 60.3 treatment was at appendectomy and every 12 h for 3 days. Survival was significantly greater in the MAb 60.3-treated group at day 10 (90 vs. 40%). Lung permeability was increased at day 2 and was not different between groups. Day 1 fluid requirements were greater in the saline-treated group. These data are consistent with MAb 60.3 protection of systemic but not pulmonary circulation in two models of sepsis.


2010 ◽  
Vol 25 (2) ◽  
pp. 169-175 ◽  
Author(s):  
Rodrigo de Faria Valle Dornelles ◽  
Vera Lúcia Nocchi Cardim ◽  
Marília Trierveiler Martins ◽  
Ana Carolina Brandão de Campos Fonseca Pinto ◽  
Nivaldo Alonso

PURPOSE: The use of springs in cranial expansion has proven to be effective in the treatment of craniosynostosis. Spring-mediated expansion has been studied both in the sagittal and in parasagittal regions, especially in scaphocephaly. A rabbit model was used in the present study to analyze the effects of springs on the cranial vault and sutures. METHODS: Thirteen 4-week-old New Zealand rabbits were divided into 4 groups: in group I, only amalgam markers were used as control; in group II, amalgam markers were used and sagittal suturectomy was performed; in group III, amalgam markers were used, a sagittal suturectomy was performed and an expansible spring was fitted in the interparietal region and in group IV, markers were used and linear parasagittal craniectomy was carried out with springs. Animals were sacrificed after 2, 4, 8 and 12 weeks. Radiological control and histological analysis were performed in the area of spring implantation. RESULTS: In the groups using springs distraction of the craniectomy borders was greater than in those that did not use springs. New bone formation was observed in all groups, and was faster in group II. Bone growth started from the borders and depth. Bone regeneration presented a similar histological pattern in the groups with spring in the sagittal and parasagittal region. CONCLUSION: The rabbit model proved to be adequate for the analysis proposed by the study. The use of springs in the groups with sagittal and parasagittal osteotomy led to a similar distraction of amalgam markers and both groups had similar ossification histological pattern.


2021 ◽  
Vol 12 (4) ◽  
pp. 54-61
Author(s):  
N. A. Sementsova ◽  
A. I. Chesnikova ◽  
V. P. Terentyev

Objective: To study the features of the parameters of 24-hour blood pressure monitoring (24h-BPM) in patients with hypertension and atherosclerosis of the arteries of the lower extremities (AALE).Materials and Methods: A total of 120 patients with hypertension were divided into 3 groups: Group I consisted of 46 patients with hypertension and clinically manifested AALE; Group II included 39 patients with hypertension and asymptomatic AALE; Group III included 35 patients with hypertension without AALE. Laboratory and instrumental studies were performed, including 24h-BPM and ultrasound triplex scanning (USTS) of the arteries of the lower extremities. Statistical analysis was performed using Microsoft Office Excel 16 (2015, Microsoft, USA), Statistica 10.0 (StatSoft, USA), IBM SPSS Statistica 26.0 (IBM, USA).Results: Higher values of systolic blood pressure (SBP) were revealed in Group I patients compared with Group III (P <0.05). Increased variability of daily average and daytime SBP were found in Group I patients (16 [13; 17] and 15.5 [12; 18] mm Hg), which significantly differed from those in Group III (P = 0.005). The patients of Group II showed higher values of diastolic blood pressure (DBP) compared with Group I (P <0.017). Higher values of pulse blood pressure (PBP) were found in Group I compared with Groups II and III (P = 0.001). In Group I, the normal type of 24-hour index of SBP was 2 times less common (P <0.017).Conclusions: The clinical manifestation of AALE is associated with higher SBP and PBP values, SBP variability and lower DBP values, which indicates a higher risk of cardiovascular complications.


Author(s):  
K.K. SEKHRI ◽  
C.S. ALEXANDER ◽  
H.T. NAGASAWA

C57BL male mice (Jackson Lab., Bar Harbor, Maine) weighing about 18 gms were randomly divided into three groups: group I was fed sweetened liquid alcohol diet (modified Schenkl) in which 36% of the calories were derived from alcohol; group II was maintained on a similar diet but alcohol was isocalorically substituted by sucrose; group III was fed regular mouse chow ad lib for five months. Liver and heart tissues were fixed in 2.5% cacodylate buffered glutaraldehyde, post-fixed in 2% osmium tetroxide and embedded in Epon-araldite.


1998 ◽  
Vol 80 (09) ◽  
pp. 393-398 ◽  
Author(s):  
V. Regnault ◽  
E. Hachulla ◽  
L. Darnige ◽  
B. Roussel ◽  
J. C. Bensa ◽  
...  

SummaryMost anticardiolipin antibodies (ACA) associated with antiphospholipid syndrome (APS) are directed against epitopes expressed on β2-glycoprotein I (β2GPI). Despite a good correlation between standard ACA assays and those using purified human β2GPI as the sole antigen, some sera from APS patients only react in the latter. This is indicative of heterogeneity in anti-β2GPI antibodies. To characterize their reactivity profiles, human and bovine β2GPI were immobilized on γ-irradiated plates (β2GPI-ELISA), plain polystyrene precoated with increasing cardiolipin concentrations (CL/β2GPI-ELISA), and affinity columns. Fluid-phase inhibition experiments were also carried out with both proteins. Of 56 selected sera, restricted recognition of bovine or human β2GPI occurred respectively in 10/29 IgA-positive and 9/22 IgM-positive samples, and most of the latter (8/9) were missed by the standard ACA assay, as expected from a previous study. Based on species specificity and ACA results, IgG-positive samples (53/56) were categorized into three groups: antibodies reactive to bovine β2GPI only (group I) or to bovine and human β2GPI, group II being ACA-negative, and group III being ACA-positive. The most important group, group III (n = 33) was characterized by (i) binding when β2GPI was immobilized on γ-irradiated polystyrene or cardiolipin at sufficient concentration (regardless of β2GPI density, as assessed using 125I-β2GPI); (ii) and low avidity binding to fluid-phase β2GPI (Kd in the range 10–5 M). In contrast, all six group II samples showed (i) ability to bind human and bovine β2GPI immobilized on non-irradiated plates; (ii) concentration-dependent blockade of binding by cardiolipin, suggesting epitope location in the vicinity of the phospholipid binding site on native β2GPI; (iii) and relative avidities approximately 100-fold higher than in group III. Group I patients were heterogeneous with respect to CL/β2GPI-ELISA and ACA results (6/14 scored negative), possibly reflecting antibody differences in terms of avidity and epitope specificity. Affinity fractionation of 23 sera showed the existence, in individual patients, of various combinations of antibody subsets solely reactive to human or bovine β2GPI, together with cross-species reactive subsets present in all samples with dual reactivity namely groups III and II, although the latter antibodies were poorly purified on either column. Therefore, the mode of presentation of β2GPI greatly influences its recognition by anti-β2GPI antibodies with marked inter-individual heterogeneity, in relation to ACA quantitation and, possibly, disease presentation and pathogenesis.


1980 ◽  
Vol 94 (3) ◽  
pp. 315-320 ◽  
Author(s):  
D. Schams ◽  
E. Stephan ◽  
R. D. Hooley

Abstract. Six Holstein bulls were housed in a climate-chamber under constant light regimen and after two weeks of preconditioning at 15°C, 60% relative humidity RH (day) and 12°C, 60% RH (night) were subjected to two weeks of heat exposure. This involved one week at 30°C and 60% RH (day) and 25°C and 60% RH (night) and a further week at 35°C, 60% RH (day) and 30°C, 60% RH (night). Three bulls were untreated (group I) and 3 bulls were treated (group II) just before and during heat exposure with a prolactin inhibitor to study the possible physiological role of prolactin on the regulation of water, potassium and sodium. Serum prolactin levels increased significantly (P < 0.01) in group I from the control value of 6 ng/ml to 33 and 44 ng/ml when the ambient temperature was increased (weeks 3 and 4) and then decreased to 21 and 12 ng/ml after reduction in temperature during weeks 5 and 6, respectively. For group II prolactin values decreased under the treatment with the prolactin inhibitor to 0.5 ng/ml and remained at this level throughout the experiment. GH levels were unaffected by heat treatment or by treatment with prolactin inhibitor. There were no differences between groups I and II in respiratory rate, pulse rate and rectal temperature. Water intake increased in both groups under heat exposure but decreased significantly afterwards only in group II. Differences in urinary excretion volume and blood serum osmolality were not significant. Urinary potassium and sodium excretion were unchanged in group II but increased with heat exposure in group I. During heat exposure 2 bulls of group II lost weight despite maintaining food intake.


Sign in / Sign up

Export Citation Format

Share Document