Effect of hypoxia on UDP-glucuronosyl transferase mRNA expression in human hepatocarcinoma functional liver celL4 cell line.

Although hypoxic conditions have been reported to affect the expression levels of various enzymes like cytochrome P450, the effect of hypoxia for UDP-glucuronosyl transferase (UGT) expression has been unclear. We evaluated the mRNA expression of UGTs (UGT1A1·1A6·1A9·2B7) in a functional liver cell-4 (FLC-4) cell line by three-dimensional culture under hypoxic conditions (37 °C, 1% O2, 5% CO2) fo 7 days. The mRNA expression of UGT1A1·1A6·1A9·2B7 decreased significantly after 3 days and that of UGT1A1·1A6·1A9 decreased significantly after 7 days. Hypoxic conditions affect the expression levels of UGT enzymes, thus the adjustment of dosage and interval should be considered in drug therapy that metabolized by UGT.

Total hip replacement rates are higher among Caucasians than Asians in Hawaii.

The etiology of hip osteoarthritis remains unknown but may involve genetic or lifestyle factors. Most cases of total hip replacement are performed because of osteoarthritis. To examine possible ethnic differences, hospital records in Hawaii from 1985 to 1989 were reviewed. Preoperative radiographs were reviewed for a subset of patients to ascertain the reason for total hip replacement. Osteoarthritis accounted for a greater percentage of total hip replacements among whites (59% for women and 66% for men) than among Japanese (36% of women and 30% of men). The incidence of total hip replacement for whites was three to 25 times greater than that of other ethnic groups (Japanese, Chinese, Filipino, and Hawaiians). For example, the risk of total hip replacement for white women 40 years to 84 years of age was 4.4%, compared with 1.1% for Japanese women and 1.7% for Chinese women of the same age group. Compared with published data, the incidence was similar for Chinese in Hawaii and San Francisco; however; whites in Hawaii had a total hip replacement incidence less than half that of whites in San Francisco. Lifestyle differences might account for the lower incidence of total hip replacement for whites in Hawaii, compared with those in San Francisco. The lower incidence among Asians suggests a possible genetic basis for osteoarthritis.

100 cemented versus 100 noncemented stems with comparison of 25 matched pairs.

Two series of 100 consecutive primary total hip arthroplasties, each using a single design of noncemented or cemented femoral component (all 28 mm heads), were compared. One cemented and two noncemented stems underwent revision for aseptic loosening. Of unrevised hips, outcome data statistically favored cemented, rather than noncemented, stems. The data for cemented and noncemented stems, respectively, were: An excellent to good result in 97% versus 88%; thigh pain in 3% versus 40%; subsidence in 0% versus 22%; and endosteal cavitation in 6% versus 12%. For patients with 25 unrevised matched pairs, selected by gender, age, diagnosis, and weight, outcome data also statistically favored cemented over noncemented stems, respectively: an excellent or good result in 25 versus 20 hips; thigh pain in two versus eight hips; and subsidence in none versus six hips. Midterm followup data for these concurrent total hip arthroplasty series of a mid 1980s design revealed prevalence of mechanical failure of 1% for cemented stems and 4% for noncemented stems. Corroborating matched pair comparison neutralized selection bias as a causative factor for these differences. These data indicate contemporary cemented femoral stem fixation is superior to second generation noncemented femoral stem fixation. Controlled comparative studies at midterm to long term followup, such as in this report, are needed to define outcome and indications for current third generation noncemented stem fixation.

Differential expression of maf-1 and maf-2 genes in the developing rat lens.

PURPOSE: To examine the expression of maf-1 and maf-2 protocogenes in the developing rat lens. METHODS: Maf-1 and maf-2 transcripts were assayed in rat lenses on embryonic days 13 and 16 (E13 and E16) by in situ hybridization using single-stranded RNA probes. Proteins encoded by the maf-2 gene were assayed immunocytochemically in embryonic (E12, 13, 16, 19) and postnatal day 14 and 90 (P14 and P90) lenses. RESULTS: In embryonic lenses, we detected maf-1 messenger RNA (mRNA) in the lens epithelium and maf-2 mRNA diffusely distributed in the lens fiber cells. By immunocytochemistry, Maf-2 was detected on E12 in the nuclei of almost all lens pit cells. On days E13, E16, and E19, however, lens epithelial cells showed no immunoreactivity, but nuclei of fiber cells reacted strongly. On P14, nuclei containing Maf-2 protein were confined to the equator of the lens, but at 3 months of age, no Maf-2 could be detected in the rat lens. Western blotting showed that the anti-Maf-2 antiserum reacted with a single protein, of molecular weight approximately 39 kDa, in rat lens. CONCLUSIONS: Results showed the spatial and temporal regulation of maf gene expression and suggest that these genes participate in transcriptional regulation during the development of the lens in the rat.

Hemodilution with other blood reinfusion techniques in total hip arthroplasty.

Acute normovolemic hemodilution has been reported to result in blood savings varying from 18% to 90%. Very few of these are randomized prospective studies. This study attempts to determine the blood transfusion savings if acute normovolemic hemodilution is used in combination with autologous predonated blood and cell saver. Thirty-three patients undergoing total hip arthroplasty were assigned randomly to one of two groups (control, n = 16; hemodilution, n = 17). Patients in both groups entered an autologous predonation program if cleared medically and were placed on Cell Saver intraoperatively and in the postanesthesia care unit. In addition, the hemodilution group underwent acute normovolemic hemodilution preoperatively. Only 41% of the patients in the hemodilution group required any autologous blood transfusion as compared with 75% of the control group. In addition, the hemodilution group required a mean lower quantity of autologous blood transfusion (41% of the estimated blood loss) as compared with the control group (71%). The net anesthesia time increased by an average of 11.4 minutes in the hemodilution group. Acute normovolemic hemodilution is a safe procedure even in an older patient population. Hemodilution resulted in fewer patients needing autologous predonated blood transfusions. The major benefit of hemodilution was seen when predonation was not possible.

Effects of patellar thickness on compression and shear forces in total knee arthroplasty.

Ten unembalmed cadaveric knees were dissected to the capsule preserving the ligamentous and tendinous structures. A posterior cruciate ligament sparing total condylar knee arthroplasty was implanted routinely. A force transducer that measured compression force and shear was implanted into each patella. For each knee, 3 thicknesses of the patellar composite (osteotomized patella, transducer, polyethylene component) were evaluated: (1) precut patellar thickness, (2) precut plus 2 mm, and (3) precut plus 4 mm. The knees were tested in an Oxford Knee Testing Rig, which allowed dynamic testing with 6 degrees of freedom. Values of patellar forces were obtained throughout a range of motion of 0 degrees to 95 degrees flexion. At higher flexion angles (45 degrees and above), the total patellofemoral shear forces for the precut plus 2 mm and the precut plus 4 mm composites were altered significantly from the precut thickness. Increasing the patellar thickness results in a significant increase in shear forces, potentially leading to early loosening of the component or increased wear or both. Therefore, bone conserving resections that increase the patellar composite thickness above the precut thickness should be avoided.

Perioperative bladder management after primary total hip arthroplasty.

A retrospective review of 95 consecutive primary total hip arthroplasty patients was performed to assess the clinical outcome of two postoperative bladder management protocols. The first 49 patients (group 1) were treated with a pro re nata straight catheterization protocol. The next 46 patients (group 2) were treated with an indwelling catheterization protocol. There were no differences between the groups with respect to sex or age. The patients in group 2 had significantly lower incidences of urinary retention (P < .0005) and bladder distention (P < .0005) than those in group 1. Preoperative systemic diseases and urologic symptoms did not correlate with the occurrence of postoperative urinary retention or bladder distention. There were no infections in group 1. In group 2, one patient (2%) had bacteriuria and one patient (2%) had a urinary tract infection (P > .1). This trend of increased contamination in the catheterization group may be related to a mean catheterization duration of 72 hours.

Recurrent hemarthrosis following a total knee arthroplasty.

The case of a recurrent hemarthrosis of a total knee arthroplasty after the sixth postoperative month is described. Because of disabling pain, the patient underwent an explorative arthrotomy 18 months after implantation of the total knee arthroplasty. A hypertrophied vascular mass of synovium was discovered in the lateral gutter and excised with an associated synovectomy. Since the arthrotomy, the hemarthrosis has not recurred. Therefore, in cases of recurrent hemarthrosis of a total knee arthroplasty that becomes disabling, exploration by arthrotomy should be considered.

Autogenous bone banking in a contralateral total hip arthroplasty. A case report.

The operative technique of autogenous bone banking of a femoral head from a symptomatic degenerative hip undergoing a primary total hip arthroplasty into an osseous deficiency of an asymptomatic, contralateral, loose acetabular component is described. The rationale for bone banking an autogenous femoral head versus the use of an allograft or iliac crest autograft at a later date is discussed.

Extreme variations in racial rates of total hip arthroplasty for primary coxarthrosis: a population-based study in San Francisco.

OBJECTIVES: To compare the incidence of all total hip arthroplasty, and total hip arthroplasty for primary coxarthrosis, among the Asian, black, Hispanic, and white populations living in one locale. METHODS: We identified all San Francisco residents who underwent total hip replacements (THR) in the 17 hospitals for adults within or near San Francisco County during a five year period. Preoperative pelvic radiographs were read without prior knowledge of the gender or race of the subject, to diagnose the specific hip diseases. Age standardised THR incidence by race and gender was determined, as was the comparative THR incidence for specific diagnosis (primary and secondary osteoarthritis). RESULTS: The greatest annual rate of total hip replacement occurred in white women (97 per 100,000 population), followed by white men, black women, black men, Hispanic women, and Hispanic men. The smallest numbers were found in Asians, whose THR rate was 10% that of whites. A primary coxarthrosis diagnosis was greatest among white subjects (66%), followed by black subjects (54%), Hispanics (53%), and Asians (28%). Age standardised THR rates for primary coxarthrosis per 100,000 population were likewise greatest among whites (43.0) and least among Asians (1.3 for Chinese). Mean age of patients undergoing THR for primary coxarthrosis was 70 years for white subjects and almost a decade younger in all other groups. CONCLUSIONS: THR rates are much lower for Asians, Hispanics, and black subjects than for the white population living in San Francisco. The low rates of total hip arthroplasty in the non-white groups was related to the much lower incidence of THR for primary coxarthrosis among non-whites than among whites. The racial distribution of primary coxarthrosis among patients who underwent THR is consistent with distribution patterns reported internationally.

Molecular analysis of T cell receptor V beta chain to detect leukemia cell clonality in patients by adaptor ligation-mediated polymerase chain reaction.

We have developed a simple and rapid method to analyze the clonality of leukemia cells. After three rounds of amplification by adaptor-ligation polymerase chain reaction (PCR), the cDNA is cut with AluI, HaeIII, RsaI, and Sau3AI, and analyzed by polyacrylamide gel electrophoresis. The size of the restriction fragments is compared to that of the published restriction fragments size each TCR-beta subfamily V region. The sensitivity of adaptor-ligation PCR restriction enzyme analysis (AL-PCR-REA) was 10(-4) MOLT-4 T-ALL cell population in the normal peripheral blood lymphocytes (PBL). Application of AL-PCR-REA to PBL and bone marrow (BM) cells from eight clinical leukemia samples indicated that a detection sensitivity was rather low, but revealed the clonality of all eight clinical samples. This AL-PCR-REA method can detect clonality without the need for either radioisotopes or sequencing procedures.

The effect of trochlear design on patellofemoral shear and compressive forces in total knee arthroplasty.

Biomechanical testing was performed on 5 cadaveric knees to evaluate the effect of patellofemoral design on shear and compressive force at the patellar component-bone interface. Three patellofemoral designs with identical tibiofemoral articular surfaces were tested. The knees were tested under dynamic loading conditions from 0 degree to 100 degrees flexion. A transducer that measured 3 orthogonal force components was mounted between the patellar component and the patella. The combination of an oval dome patella with a 2-mm deeper trochlear groove and associated increased femoral resection was compared with a biconcave patella with standard trochlea and normal femoral resection. Alignment of the trochlear groove in 7 degrees valgus (anatomic) decreased medial-lateral shear by 10% to symmetric trochlear groove alignment.

Postoperative surveillance for deep venous thrombosis with duplex ultrasonography after total knee arthroplasty.

Duplex ultrasonography of the lower extremity was used for routine non-invasive screening for asymptomatic proximal and distal deep venous thrombosis, for monitoring of potential propagation of deep venous thrombosis from distal to proximal, and for confirmation of the resolution of proximal deep venous thrombosis after treatment. In the first part of the study, to substantiate the accuracy of duplex ultrasonography, 130 lower limbs (seventy-nine patients) were studied with that modality as well as with venography after a total hip or total knee arthroplasty. Compared with venography, duplex ultrasonography demonstrated 100 per cent sensitivity, specificity, and accuracy for the detection of proximal deep venous thrombosis and 88 per cent sensitivity, 98 per cent specificity, and 98 per cent accuracy for the detection of distal deep venous thrombosis. In the second part of the study, 100 patients who had had a total knee arthroplasty and had been managed with pneumatic stockings and aspirin for prophylaxis against deep venous thrombosis had screening of both lower extremities with duplex ultrasonography on the fourth postoperative day. Duplex ultrasonography demonstrated proximal deep venous thrombosis in seven patients and distal deep venous thrombosis in twenty-two patients; all twenty-nine patients were asymptomatic. The patients who had distal deep venous thrombosis had surveillance with serial duplex ultrasonography on the seventh and fourteenth postoperative days; five of these patients were found to have had propagation of the thrombosis to the proximal deep veins.(ABSTRACT TRUNCATED AT 250 WORDS)

The clinical course of distal deep venous thrombosis after total hip and total knee arthroplasty, as determined with duplex ultrasonography.

Duplex ultrasonography was used to screen 273 consecutive patients, on the fourth day after a total hip or total knee arthroplasty, for the presence of a distal deep venous thrombosis. Patients who had a history of thromboembolic disease or who had an active neoplasm were excluded from the study. Of the 273 patients, twenty-four (9 per cent) were found to have a proximal deep venous thrombosis (a thrombosis involving the femoral or popliteal veins) and forty-one (15 per cent), a distal deep venous thrombosis (a thrombosis involving the veins of the calf). All of the thromboses were asymptomatic. The forty-one patients in whom a distal deep venous thrombosis had been detected with duplex screening subsequently had serial duplex examinations, on the seventh and fourteenth postoperative days. If a proximal deep venous thrombosis was detected, anticoagulation was begun immediately. If no proximal thrombosis was observed, the distal thrombosis was considered stable, the serial duplex examinations were terminated, and clinical observation was continued. Of the forty-one patients who had serial examinations, seven (17 per cent) had a proximal deep venous thrombosis in the ipsilateral limb by the fourteenth postoperative day; all seven were asymptomatic, and all were managed with anticoagulation. Thirty-four patients (83 per cent) were determined to have a stable distal deep venous thrombosis on the fourteenth postoperative day, and no additional duplex examinations were performed. Thirty-three (97 per cent) of these thirty-four patients remained asymptomatic for deep venous thrombosis thereafter; the remaining patient (3 per cent) had a proximal deep venous thrombosis in the ipsilateral limb eleven months postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Routine postoperative duplex ultrasonography screening and monitoring for the detection of deep vein thrombosis. A survey of 110 total hip arthroplasties.

The use of duplex ultrasonography for routine noninvasive screening, monitoring, and management of deep venous thrombosis after total hip arthroplasty was evaluated. The reliability of duplex ultrasonography for detection of deep vein thrombosis was confirmed in an initial cohort of 51 total hip arthroplasty patients (102 lower extremities), demonstrating 91% sensitivity, 98% specificity, and 97% accuracy when compared with venography. A second cohort of 110 total hip arthroplasty patients using pneumatic compression stockings and aspirin as deep vein thrombosis prophylaxis underwent screening duplex ultrasonography of both lower extremities on postoperative Day 4. Duplex ultrasonography screening showed 10 (9.1%) patients with proximal deep vein thrombosis and 10 (9.1%) with distal deep vein thrombosis, all of whom were asymptomatic. The 10 patients with proximal deep vein thrombosis on duplex ultrasonography were prescribed therapeutic anticoagulation. Duplex ultrasonography subsequently confirmed resolution of proximal deep vein thrombosis in these patients before discontinuation of anticoagulation; none developed symptomatic pulmonary embolism through 12-month clinical followup. The 10 patients with distal deep vein thrombosis diagnosed by duplex ultrasonography were not treated with anticoagulation, but were monitored by serial duplex ultrasonography through postoperative Day 14 for propagation of distal to proximal deep vein thrombosis; none manifested symptomatic deep vein thrombosis or pulmonary embolism through 12-month clinical followup. The 90 patients with negative duplex ultrasonography results were followed clinically; 3 developed late symptomatic proximal deep vein thrombosis (1 of these later manifested pulmonary embolism). Therefore, duplex ultrasonography was used after total hip arthroplasty for the following: (1) to screen routinely in the hospital for asymptomatic proximal and distal deep vein thrombosis; (2) to monitor for potential propagation of distal to proximal deep vein thrombosis; (3) to minimize exposure to therapeutic anticoagulation by confirming the absence of proximal deep vein thrombosis in 97 of 110 patients; and (4) to demonstrate the effectiveness of mechanical and systemic deep vein thrombosis management by confirming the absence or resolution of deep vein thrombosis in all 110 patients.

The femoral component in total hip arthroplasty. Six to eight-year follow-up of one hundred consecutive patients after use of a third-generation cementing technique.

One hundred consecutive patients had a primary unilateral total hip arthroplasty with use of a single design of the femoral component (Harris Precoat), inserted with a so-called third-generation cementing technique, between July 1985 and June 1987. There were seventy-four women and twenty-six men. The mean age at the time of the operation was seventy-one years (range, forty-one to ninety-two years) and the mean weight was seventy kilograms (range, forty-eight to 105 kilograms). Eleven of the 100 patients died during the follow-up period, all with the implant in place. Of the eighty-nine surviving patients, one had a revision arthroplasty for aseptic loosening. The mean duration of clinical follow-up for the remaining eighty-eight patients was seven years (range, six to eight years). The mean Harris hip score at the latest follow-up evaluation was 91 points (range, 68 to 97 points). Of the eighty-eight patients, eighty-five (97 percent) had a good or excellent result. Radiographic follow-up was performed for eighty-one patients; none had evidence of loosening of the stem, and five (6 percent) had endosteal cavitation but were asymptomatic. The rate of failure (loosening or revision) of the femoral component in the entire series was 1 per cent (one hip). The low rate of failure and the maintenance of good and excellent clinical and radiographic results during this period of follow-up are consistent with reports from other institutions. This strengthens the argument to retain or widen the existing indications for the insertion of a femoral stem with cement in primary total hip arthroplasty.

Use of parenteral prophylactic antibiotics in clean orthopaedic surgery. A review of the literature.

Parenteral prophylactic antibiotics are now a routine part of most clean orthopaedic procedures since so many animal and clinical studies have shown a reduced infection rate with their use. First-generation cephalosporins are theoretically the preferred agents, and the pharmacokinetics of Cefazolin make it the drug of choice. It is imperative that an antibiotic be given on the induction of anesthesia or at least ten minutes before inflation of a tourniquet. Based on evidence in the current literature, 24 hours of postoperative coverage appears to be adequate.

The role of non-invasive vascular studies in determining levels of amputation.

Various non-invasive vascular studies have been reported to provide valuable data for selection of the optimum level of amputation in limbs in patients who have vascular disease. We evaluated three such methods: (1) measurement of the change in the transcutaneous PO2 after inhalation of oxygen; (2) determination, by the Doppler method, of segmental blood pressure; and (3) measurement of the temperature of the skin. The records of eighty patients (ninety amputations) were retrospectively reviewed for correlations between the results of the vascular studies and the outcome of the amputation. Measurement of transcutaneous PO2 was found to be the most accurate predictor of successful healing of an amputation; the other two measurements were less reliable. The values for transcutaneous PO2 both at rest and after inhalation of oxygen were significantly different (p less than 0.001) for the patients who had a healed amputation compared with those who had a failed amputation. Regardless of the initial value, if, after inhalation of oxygen, the transcutaneous PO2 reached ten millimeters of mercury or more, it predicted healing of the amputation stump with a sensitivity of 98 per cent. When the level of amputation was selected on the basis of clinical judgment at the time of operation, the sensitivity was only 90 per cent.