The protective effect of anterior cruciate ligament reconstruction on articular cartilage: a systematic review of animal studies

OBJECTIVE

It is unclear if anterior cruciate ligament (ACL) reconstruction can prevent the onset of degenerative changes in the knee. Previous studies were inconclusive on this subject. The aim of this study was to systematically review all studies on the effect of ACL reconstruction on articular cartilage in animals.

DESIGN

Pubmed and Embase were searched to identify all original articles concerning the effect of ACL reconstruction on articular cartilage compared with both its positive (ACL transection) and negative (sham and/or non-operated) control in animals. Subsequently a Risk of bias and meta analysis was conducted based on five outcomes (gross macroscopic assessment, medical imaging, histological histochemical grading, histomophometrics and biomechanical characterization) related to articular cartilage.

RESULTS

From the 19 included studies, 29 independent comparisons could be identified which underwent ACL reconstruction with an average timing of data collection of 23 weeks (range 1-104 weeks). Due to limited data availability meta-analysis could only be conducted for gross macroscopic damage. ACL reconstruction caused significant gross macroscopic damage compared with intact controls (SMD 2.0 [0.88; 3.13]). These findings were supported by individual studies reporting on histomorphometrics, histology and imaging. No significant gross macroscopic damage was found when ACL reconstruction was compared with ACL transection (SMD -0.64 [-1.85; 0.57]).

CONCLUSION

This systematic review with an average follow up of included studies of 23 weeks (range 1-104 weeks) demonstrates that, in animals, ACL reconstruction does not protect articular cartilage from degenerative changes. The consistency of the direction of effect, provides some reassurance that the direction of effect in humans might be the same.

Clinical case management: what works, what doesn't

Often, what works best depends less on a specific model, and more on choosing the right people. Two nurses were selected to role model critical path and case management principles. These clinical care coordinators focused on all involved disciplines, cost containment and quality outcomes.

[Comparison of in vitro action of cetylpyridinium chloride containing preparations]

The fungicidal efficacy on Candida albicans of cetylpyridinium chloride (CAS 123-03-5) solution (CPC I solution, Dobendan) in various dilutions was tested with help of the quantitative suspension test and compared with CPC containing self-made preparations with or without addition of alcohol. The dilution of all test preparations caused an impairment of antimicrobial efficacy; the activity was reduced distinctly: due to a 50% dilution a decrease of 2-3 ten's powers was observed. The reduction of efficacy of the self-made preparation was less pronounced. The addition of 1% albumin as well impaired the fungicidal activity of all test preparations. CPC + alcohol revealed the most pronounced fungicidal efficacy; no differences were seen between CPC (without alcohol) and CPC I solution.

Predictive value of serum alkaline DNase activity variations in treatment of head and neck cancer

The aim of this study was to evaluate the variation in serum alkaline DNase activity (SADA) as a means of therapeutic monitoring in patients with head and neck cancer. Blood samples from 40 patients were collected before, during, and some weeks up to months after therapy. A decrease in SADA during treatment was usually associated with a primary clinical response, while no decrease indicated non-response to therapy. In patients with complete tumor regression the initial decrease of SADA was usually followed by an increase exceeding the initial level. A similar increase was not observed in patients with tumor progression.

Correlation between size and external temperature in four rat tumours after treatment with cytostatic agents

The reduction in size of four experimental tumours (ISIS 130 and ISIS 208 immunocytomas, S 437 mammary adenocarcinoma, S 447 colon adenocarcinoma) was investigated in LOU rats under the influence of cytostatic agents belonging to different classes (5-fluorouracil, methotrexate, vinblastine, cisplatin, doxorubicin, cyclophosphamide). External tumour and rectal temperatures were measured at the same time, twice daily, during the whole experiment. With the rectal temperature of the rats kept constant, the reduction in tumour dimensions following chemotherapy correlated via a linear relationship with the duration and degree of tumour hypothermia for the three tumours S 437, ISIS 208, ISIS 130. However, for the same reduction in tumour volume following chemotherapy, the duration and degree of transient tumour hypothermia varied according to the type of tumour and cytostatic agent studied. There was not correlation between the decrease in size of S 447 and external tumour hypothermia. Even when the reduction in tumour size was statistically significant, the hypothermic tumour phase after drug administration was not sufficient to be significant, except for vinblastine. However, the temperature of this slowly growing tumour before chemotherapy was particularly low. The measurement of the degree and duration of external tumour hypothermia of tumours following chemotherapy would represent a new physiological technique for measuring the efficacy and duration of action of cytostatic agents.

Correlation between size and external temperature of the ISIS 130 tumour after treatment with cytostatic agents

The reduction in size of the experimental ISIS 130 tumour has been investigated in LOU rats under the influence of increasing doses of cytostatic agents belonging to different classes. External temperatures of tumours as well as rectal temperatures have been measured at the same time, twice daily, during the whole experiment. The greater the decrease in the tumour size after drug administration, the larger was the decrease in external temperature of tumour. The rectal temperatures remained fairly stable, thus differences between the tumour and rectal temperatures increased. A possible correlation between the reduction of tumour size and the decrease of external temperature of tumour has been traced for every cytostatic agent, and the same linear relationship has been found to link these two parameters. The decrease in external temperature of tumour may, moreover, predict the decrease in tumour size within a term of 1-2 days. Measurement of the magnitude of the transient tumour hypothermia of ISIS 130, following chemotherapy, would represent a new method for measuring the efficiency and duration of action of cytostatic agents.

Effect of chemotherapy on tumor temperature in rats

Two transplanted rat immunocytomas with different degrees of sensitivity to single injection of cyclophosphamide (CY) were used to assess the reliability of recording of the tumoral and rectal temperatures may be useful to evaluate the efficacy of cytostatic drugs against experimental rat tumors. With the highly sensitive tumor (ISIS 130), 25 mg/m2 of CY resulted in a pronounced tumor inhibition (Treated/Control tumors = 28%); with the less sensitive (ISIS 208), a CY dose of 320 mg/m2 was necessary to inhibit tumor growth to the same extent. The more important the decrease in tumor size was, after the administration of the drug, the larger the decrease was in tumoral temperature. Since the rectal temperature remained fairly stable, there was an increase of the difference between the tumoral and rectal temperatures. From the comparison between the results obtained for the two tumors with a wide range of CY doses, it appeared that the decrease in tumoral temperature did not correlate with the drug dose itself, but with the actual antitumor efficacy of the drug in each particular case.

Radioimmunodetection of primary and metastatic germ cell tumors containing alpha-fetoprotein

Radioimmunodetection with an 131I anti-alpha-fetoprotein (alpha FP) has been performed in 5 patients with germ cell tumors. In 3 of them, 5 of 6 recognized or suspected tumor sites could be demonstrated. In 1 of these patients, a clinically non-apparent primary tumor was detected by this method. The 2 other patients had received intensive chemotherapy and had a persistent elevation of serum alpha FP, although usual paraclinical examinations were normal. In these patients, the labelled antibody scan did not show any abnormality. These results suggest that radioimmunodetection can be useful in patients with nonseminomatous gonadal and extragonadal tumors at the time of presentation. Usefulness of radioimmunodetection in the follow-up of these patients remains to be determined. Even in our limited series, radioimmunodetection was of no help on localizing the sites of alpha FP secretion in treated patients in whom other methods had also failed to recognize the site of abnormal alpha FP synthesis.

Laboratory rat associated outbreak of haemorrhagic fever with renal syndrome due to Hantaan-like virus in Belgium

Hantaan-like virus was identified as the cause of three cases of acute renal failure in staff handling laboratory rats on a Belgian university campus. Serological studies revealed infected rat strains at different sites on the campus and evidence of past and recent infections in 39 staff members and of infection in 50% of exposed staff. Hantaan-reactive antibody was very rare in control populations. Staff or rats at three other Belgian institutions had no signs of infection. The origin of the virus was not identified. Infected rats have been removed. These are the first confirmed cases, outside East Asia, of human illness due to rat-borne Hantaan-like virus, and of infection in laboratory rats. Surveillance of rat colonies is also recommended in countries which, like Belgium, have no previously recognised cases of haemorrhagic fever with renal syndrome.

A transplantable immunocytoma of the rat as a model for the study of immunoglobulin secretion

An immunoglobulin secreting tumor appeared spontaneouldy in the LOU/Dec rat strain in an incidence of about 3--5% at age 8-20 months. Attempts to increase the incidence using such things as genetic selection, carcinogens, immunosuppressants, adjuvants, cell-free fumor material, and antigenic stimulation were unsuccessful. The tumor was found to be easily transplanted. It secreted monocolonal immunoglobulins related to most of the normal rat immunoglobulins: IgG, IgA, IgM, IgE, and some light chains. Some tumor lines were found to be sensitive to chemotherapy. Tumor-bearing rats, cured by chemotherapy, were found to be resistant to subsequent challenge graft of the tumor. The resistant state could be transferred from one animal to another by parabiosis or peritoneal exudate, but not by way of serum. It was concluded that the tumor-bearing LOU/Dec rat is an excellent model for studies of immunoglobulin secretion, and the cured, resistant rat is an excellent model for studies of cell mediated immunity.

Improvement in measuring migration areas in migration inhibition assays

An improved method for measuring migration areas in migration inhibition assays is described. In this method, drawings of the projected image are analysed with an image analysis system. This method is faster as well as more accurate than a standard method.

A simple procedure for identification of macrophages in peritoneal exudates

Identification of peritoneal exudate macrophages by labelling with China ink followed by May-Grünewald Giemsa staining was investigated as a simple and reliable procedure to differentiate these cells from the largest lymphoid cells. This procedure was compared with techniques which reveal acid phosphatase activity and which vitally stain lysosomes (neutral red). The cells were further separated in adherent and nonadherent populations for investigation by the three described techniques. The results showed that all three techniques revealed the same type of cells with a good correlation between enzymatic activity, presence of lysosomes, phagocytic activity and adherence. China ink labelling of peritoneal exudate cells is a simple and reliable method for routine identification of macrophages. It is suggested that functions required for in vitro tests of cellular immunity should be preserved in cells identified in this way.

A comparative study of the proteins of rat plasma, liver and hepatoma by agarose immunoelectrophoresis

A convenient and selective microtechnique, agarose immunoelectrophoresis, was applied to a comparison of the antigens in rat liver and plasma, and in primary hepatoma induced in male Fischer strain rats with N-2-fluorenylacetamide or N-hydroxy-N-2-fluorenylacetamide. Of the many soluble proteins antigenic in this system, 3 were singled out for detailed study. The albumin in liver and hepatoma had a higher mobility than that in plasma. Extraction of the soluble fraction of rat liver with ether, or treatment with absorbing charcoal, yielded an albumin band with a mobility identical to that in plasma, suggesting that liver albumin carries absorbed molecules with electronegative charges. The transferrin arc from liver, plasma and hepatoma had identical mobility. One protein with low mobility was present in higher concentration in the soluble liver fraction of male than of female rats, but it was reduced in hepatoma of male rats. The "h(2)" proteins of liver were found in the cathodic region as 5 arcs, some of which were reduced, while others were not detectable in hepatoma.