PubMed Health⌕ Search

Biomedical subjects

F M Griffin

Publications and source records attributed to F M Griffin.

At least 19 recordsLinked to original sources

Anatomy of the epicondyles of the distal femur: MRI analysis of normal knees.

Knowledge of precise anatomic landmarks and relationships of the distal femur can be helpful in knee surgery, especially primary and revision total knee arthroplasty. We analyzed 104 consecutive routine knee magnetic resonance imaging studies to define useful landmarks and relationships. The epicondyles are described, and the relationship of the epicondyles to the joint line is defined in multiple planes. Some significant gender differences were noted. The distance from the epicondyles to the joint line correlates with the transepicondylar width of the distal femur. This information can be helpful in determining appropriate joint line position intraoperatively. The posterior condylar angle averaged 3.11 degrees for all patients, and a tendency for the posterior condylar angle to increase with age was noted, but further study of this tendency is needed.

Adolescent↗

Accuracy of soft tissue balancing in total knee arthroplasty.

To the best of our knowledge, this is the first study to assess the accuracy of balancing of the flexion and extension gaps in total knee arthroplasty (TKA). Measurements of the heights of the flexion and extension gaps were obtained during 104 consecutive primary, posterior-stabilized TKAs in osteoarthritic patients. Clinically, all knees appeared to be well balanced intraoperatively. Rectangular flexion and extension gaps almost always were obtained within 1 mm (84%-89%). None of the knees was >3 mm from being perfectly rectangular. Equality of the flexion and extension gaps was more difficult to obtain (47%-57% were within 1 mm). With meticulous attention, perfect soft tissue balance is not always achieved in TKA.

Arthroplasty, Replacement, Knee↗

The posterior condylar angle in osteoarthritic knees.

The posterior condylar angle is formed by the transepicondylar axis and the tangent line to the posterior condyles. It is an important relationship to determine rotational alignment of the femoral component in total knee arthroplasty. We measured this angle directly in 107 osteoarthritic knees undergoing total knee arthroplasty. The posterior condylar angle was significantly greater in valgus knees than in other osteoarthritic knees. Given the standard deviations and ranges of values noted, the posterior condyles are potentially unreliable references for femoral component rotation in some knees.

Adult↗

Osteolysis associated with cemented total knee arthroplasty.

Osteolysis has not been mentioned as a complication or cause of failure of cemented total knee arthroplasties in long-term follow-up studies. We are aware of a single case report of osteolysis after cemented total knee arthroplasty. We report the case of an 87-year-old woman with massive osteolysis beneath a cemented tibial component.

Aged↗

Total knee arthroplasty in patients who were obese with 10 years followup.

The 10-year results of primary total knee arthroplasty in patients who were obese were evaluated. In a 2-year period, 120 patients had 165 primary, posterior stabilized, cemented total knee replacements with metal backed tibial components. After exclusions, 56 patients (73 knees) were available for study. Twenty-two patients (32 knees) were classified as obese, and 34 patients (41 knees) were classified as nonobese. At 10 years followup, patients who were obese had lower Knee Society function scores than had the patients who were nonobese (mostly attributable to more difficulty with stair climbing). Patients who were obese had poorer patellar scores at 10 years. Bilaterality was more common in patients who were obese and preoperative knee scores were lower. Minor nonprogressive radiolucent lines were seen more commonly in the patients who were obese. Overall, however, 10-year Hospital for Special Surgery scores and Knee Society scores for patients who were obese were comparable with scores for patients who were nonobese and given lower preoperative Hospital for Special Surgery scores, improvement in knee score was greater. Revision rates in patients who were obese were not higher than in patients who were nonobese at 10 years followup. More study is needed of the subgroup of patients who were morbidly obese.

Aged↗

Case report: neutrophilic CSF pleocytosis in hypertensive encephalopathy.

A patient with hypertensive crisis developed encephalopathy with a lumbar puncture revealing neutrophilic pleocytosis. No explanation for her case could be found, eg, no evidence of infection or vasculitis. It is concluded that the most probable cause of her neutrophilic cerebrospinal fluid pleocytosis is hypertensive encephalopathy.

Adult↗

C3bi/CR3 is a main ligand-receptor interaction in attachment and phagocytosis of C3-coated particles by mouse peritoneal macrophages.

We investigated the relative role of C3bi-CR3 interaction in the binding and phagocytosis of EAC43 by mouse peritoneal macrophages. Anti-Mac-1 F(ab')2 markedly inhibited the binding and lymphokine-induced phagocytosis of both EAC43b and EAC43bi. Fifty per cent inhibition of attachment and phagocytosis occurred at 1 microgram/ml of anti-Mac-1 F(ab')2 in the incubation media. On the other hand, EIgG binding and phagocytosis were not inhibited at all even at a concentration of 10 micrograms/ml. Depletion of divalent cations from the incubation media abolished EAC43b and EAC43bi rosettes but not EIgG rosettes or phagocytosis. These data suggested that both EAC43b and EAC43bi binding to macrophages were mediated via CR3. Because a drastic decrease of EAC43bi rosettes was observed in the case of EAC43bi cells prepared with smaller amounts of C3, a small contamination of C3bi molecules on EAC43b, itself, cannot explain the efficient attachment of EAC43b. We propose that EAC43b on the macrophage surface can be quickly converted to EAC43bi, forming EAC43bi rosettes, and that those erythrocytes are vigorously ingested by lymphokine-activated macrophages. In accordance with this hypothesis, we demonstrated that EAC43b was converted to EAC43bi in the medium in which macrophages had been incubated.

Animals↗

In vitro elution characteristics of commercially and noncommercially prepared antibiotic PMMA beads.

The successful treatment of osteomyelitis with commercially prepared gentamicin-polymethylmethacrylate (PMMA) (Septopal) beads and surgical debridement has led to the use of this technique in the United States. However, commercially prepared gentamicin-PMMA beads are not currently available to orthopedic surgeons in the United States. Therefore, these surgeons commonly manufacture their own antibiotic-containing cement beads in the operating room at the time of surgery. There is little data that compare the antibiotic elution characteristics of such preparations to commercially prepared gentamicin-PMMA beads. This study compares the measured amount of antibiotic elution of either gentamicin or tobramycin from laboratory manufactured Zimmer, Simplex, or Palacos beads to commercially prepared gentamicin-PMMA (Septopal) beads. During a 30-day study period, commercially prepared gentamicin-PMMA beads eluted more total antibiotic and maintain higher concentrations than did antibiotic acrylic composites manufactured in the authors' laboratory.

Bacteroides↗

High concentrations of bacterial lipopolysaccharide, but not microbial infection-induced inflammation, activate macrophage C3 receptors for phagocytosis.

Macrophage C3 receptors are normally immobilized in the plane of the cells' plasma membrane and are unable to promote phagocytosis even though they promote avid particle binding. We have previously identified a lymphokine that activates macrophage C3 receptors for phagocytosis both in vitro and in vivo, and others have found that certain types of nonimmunologically mediated inflammation are also able to activate mononuclear phagocyte C3 receptors. These findings raised the possibility that macrophage C3 receptor activation is a universal consequence of inflammation. We sought in the present experiments to determine whether or not inflammation induced by microbial infection in a nonimmune host resulted in activation of macrophage C3 receptors. We injected mice i.p. with either viable microorganisms, microbe-containing immune complexes, or bacterial LPS. Macrophages were harvested by peritoneal lavage 4 days later; nearly all lavage fluids grew the microorganism with which the mouse had been injected, indicating that an infection had been established. Monolayers of macrophages were established and their interaction with sheep E coated with C3 (EIgMC) was determined. All macrophages bound EIgMC, but only macrophages from mice injected with either very high concentrations of LPS or microbe-containing immune complexes ingested them. C3 receptors of macrophages that ingested EIgMC were mobile; others were not. Thus, inflammation induced by microbial infection does not commonly, if at all, activate macrophage C3 receptors; microbe-containing immune complexes and high concentrations of LPS do. The mechanism of receptor activation in each case is C3 receptor mobilization, which is probably mediated by a lymphokine.

Animals↗

Lipolytic surface remnants of triglyceride-rich lipoproteins are cytotoxic to macrophages but not in the presence of high density lipoprotein. A possible mechanism of atherogenesis?

Hypertriglyceridemic (HTG) serum, lipolyzed in vitro by purified bovine milk lipoprotein lipase, was found to be cytotoxic to cultured macrophages. Surviving macrophages contained numerous lipid inclusions similar to those found in foam cells. Individual lipoprotein fractions isolated from the lipolyzed HTG serum, including HDL, were also cytotoxic. Lipolysis of isolated lipoprotein fractions (either HTG or normal) allowed localization of cytotoxicity to postlipolysis remnant VLDL and chylomicron particles. The presence of a critical concentration of HDL in either the lipolysis mixture or the culture dishes inhibited the cytotoxicity. Below this critical concentration HDL itself became cytotoxic, producing lipid inclusions in surviving macrophages. The lipid fraction of the cytotoxic remnants contained the cytotoxic factor(s); neither FFA nor lysolecithin alone could account for this cytotoxicity. Postprandial lipemic sera from subjects with a brisk chylomicron response, when lipolyzed in vitro, were cytotoxic to cultured macrophages; neither fasted sera from these subjects, nor postprandial sera from normolipidemic subjects with a normal chylomicron response, were cytotoxic. Postheparin (in vivo lipolyzed) serum and its isolated lipoprotein fractions obtained 30 min after heparin injection in subjects with HTG were shown to be cytotoxic to macrophages; by 60 min most of the cytotoxicity had disappeared. The postprandial and postheparin observations support an in vivo significance for remnant-associated cytotoxicity. We hypothesize that cytotoxic remnants of lipolyzed VLDL and chylomicrons may be one of the major atherogenic lipoproteins. Further, we suggest that inhibition of the cytotoxicity of these remnants may be one important way that HDL prevents atherosclerosis.

Animals↗

Neoplastic meningitis with eosinophilic pleocytosis in Hodgkin's disease: a case with cerebellar dysfunction and a review of the literature.

A 31-year-old man had Hodgkin's disease (stage IIA, nodular sclerosis) in apparent remission after radiotherapy. Nine months after the diagnosis of Hodgkin's disease, he developed neoplastic meningitis with eosinophilic pleocytosis and neurologic findings suggestive of peri-fourth ventricle infiltration. Morphologic and surface marker analysis of cerebrospinal fluid cells showed large numbers of T-lymphocytes and Reed-Sternberg variant cells positive for CD15, the Lex hapten expressed on myeloid cells and on a variety of malignant cells. Therapy with intrathecal methotrexate, oral dexamethasone, and cranial irradiation resulted in prompt resolution of his cerebrospinal fluid abnormalities and neurologic deficits. Ten months after the diagnosis of eosinophilic meningitis, systemic relapse of Hodgkin's disease occurred in right iliac and inguinal lymph nodes. The diagnosis, pathogenesis, and therapy of this unusual complication of Hodgkin's disease are reviewed.

Adult↗

Peripheral blood mononuclear leukocytes release a mediator(s) that induces phagocytosis of C-reactive protein-coated cells by polymorphonuclear leukocytes.

We studied the phagocytosis by human polymorphonuclear leukocytes (PMN) of sheep erythrocytes (E) passively sensitized with pneumococcal C-polysaccharide (E-PnC), E-PnC coated with C-reactive protein (E-PnC-CRP), and E coated with rabbit antisheep E IgG (E-IgG). PMN isolated from the blood of normal individuals failed to ingest either E-PnC or E-PnC-CRP; however, after incubation with supernatants from stimulated peripheral blood mononuclear leukocytes, glass-adherent PMN ingested E-PnC-CRP with a mean phagocytic index of 47.8 +/- 14.9 (means +/- SD, n = 9) and E-PnC to a lesser extent with a phagocytic index of 9.6 +/- 2.9 (mean +/- SD, n = 4). We also observed a statistically significant increase in the ingestion of E-IgG by lymphokine-stimulated PMN with phagocytic indices of 85.2 +/- 21.2 (mean +/- SD, n = 12) for unstimulated PMN and 158 +/- 37.1 (mean +/- SD, n = 9) for stimulated PMN. The best conditions for stimulating release of this phagocytosis-promoting mediator included exposure to phytohemagglutinin (PHA) in the presence of monocytes that had ingested IgG-coated sheep erythrocytes. The induction of phagocytosis of E-PnC-CRP was rapid, reaching a maximal level after stimulation of the adherent PMN with the conditioned media for 30 min. The factor(s) responsible for the induction of the ingestion of E-PnC-CRP was less than 10,000 daltons and was heat stable (56 degrees C for 45 min). These data are similar to earlier results obtained with PMN activated by 12-0-tetradecanoyl-phorbol-13-acetate (PMA), an important contrast being that in the current studies PMN were activated by a soluble factor released from stimulated mononuclear cells under conditions simulating those in vivo.

Biological Products↗

Stimulation of human neutrophil Fc receptor-mediated phagocytosis by a low molecular weight cytokine.

Human neutrophil Fc receptor-mediated phagocytosis can be markedly enhanced by a low m.w. (less than 10,000) heat-labile cytokine(s) derived from specifically stimulated human mononuclear cells and from a human T cell line, MO(t). PMN incubated with supernatant from control mononuclear leukocyte (MNL) culture bound EIgG (percentage of rosettes = 73.7% +/- 7.1) but did not ingest the attached targets (phagocytic index, PI = 40.7 +/- 9.5) as efficiently as PMN incubated with supernatant from adherent MNL, which had ingested EIgG and were then cocultured with nonadherent MNL (PI = 264.3 +/- 46.3). Cytokine-containing supernatants were fractionated on YM-10 Centricon microconcentrators, and the effluent (YM-10E) was found to contain the phagocytosis-enhancing activity. Optimal Fc receptor-mediated ingestion by YM-10E-stimulated PMN required a critical level of target-bound IgG; stimulation was dose dependent and detectable after 5 min at 37 degrees C with a maximal response by 15 min. Monoclonal antibody 3G8 (anti-PMN Fc receptor) inhibited in a dose-dependent fashion both Fc receptor-mediated rosette formation and ingestion by nonstimulated and YM-10E-stimulated PMN. Solid-phase 3G8 Fab had the same effect. A previously undescribed monoclonal antibody, 1C2, exhibited a different pattern of inhibition. It had no effect on rosetting or ingestion of EIgG by nonstimulated PMN; however, it inhibited EIgG phagocytosis by YM-10E-stimulated PMN down to the level of nonstimulated ingestion without affecting rosette formation. Solid-phase 1C2 had the same effect. These data indicate that phagocytosis mediated by 3G8-positive Fc receptors may be enhanced by cytokine(s) stimulation in a manner requiring the molecule recognized by 1C2. Monoclonal antibodies to the alpha-chain of CR3 had only minimal effects on YM-10E-stimulated ingestion. Fluorescence flow cytometry of YM-10E-stimulated PMN, indirectly stained with 3G8 or 1C2, indicated that cytokine enhancement of EIgG ingestion occurred without an increase in either 3G8 or 1C2 binding sites. These data show that the low avidity Fc receptor, which binds immune complexes, may be functionally modulated at sites of inflammation where PMN and macrophages mediate clearance and destruction of immune complexes and opsonized particles.

Antibodies, Monoclonal↗

Isolation of human complement component C3 from small volumes of plasma.

A method for the isolation of 8-10 mg of human C3 from 20 ml of plasma is described. The procedure is simple and rapid with excellent yields in hemolytic activity (74%) and antigenic activity (68.7%). It consists of polyethylene glycol precipitation, DEAE-Sephacel chromatography, and immunoadsorption. The final product is free of contaminating proteins as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The simplicity and speed of this procedure allow for the continual availability of hemolytically active C3.

Chemical Precipitation↗