Bone aluminum measured in miners exposed to McIntyre powder.

A small pilot study was conducted to test whether the technique of in vivo neutron activation analysis could measure bone aluminum levels in 15 miners who had been exposed to McIntyre Powder over 40 years prior. All miners were over 60 years of age, had worked in mines that used McIntyre Powder, and were sufficiently healthy to travel from northern to southern Ontario for the measurements. Individual aluminum levels were found to be significantly greater than zero with 95% confidence (p < 0.05) in 7 out of the 15 miners. The inverse variance weighted mean of the 15 participants was 21.77 ± 2.27µgAl/gCa. This was significantly higher (p < 0.001) than in a group of 15 non-occupationally exposed subjects of a comparable age from Southern Ontario who had been measured in a previous study. The inverse variance weighted mean bone aluminum content in the non-occupationally exposed group was 3.51 ± 0.85µgAl/gCa. Since the use of McIntyre Powder ceased in 1979, these subjects had not been exposed for more than 40 years. Calculations of potential levels at the cessation of exposure in the 1970s, using a biological half-life of aluminum in bone of 10 to 20 years predicted levels of bone aluminum comparable with studies performed in dialysis patients in the 1970s and 1980s. This pilot study has shown that the neutron activation analysis technique can determine differences in bone aluminum between McIntyre Powder exposed and non-exposed populations even though 40 years have passed since exposure ceased. The technique has potential application as a biomarker of exposure in cross-sectional studies of the health consequences of exposure to McIntyre Powder.

The role of patient factors and implant position in squeaking of ceramic-on-ceramic total hip replacements.

We investigated factors that were thought to be associated with an increased incidence of squeaking of ceramic-on-ceramic total hip replacements. Between June 1997 and December 2008 the three senior authors implanted 2406 primary total hip replacements with a ceramic-on-ceramic bearing surface. The mean follow-up was 10.6 years. The diagnosis was primary osteoarthritis in each case, and no patient had undergone previous surgery to the hip. We identified 74 squeaking hips (73 patients) giving an incidence of 3.1% at a mean follow-up of 9.5 years (4.1 to 13.3). Taller, heavier and younger patients were significantly more likely to have hips that squeaked. Squeaking hips had a significantly higher range of post-operative internal (p = 0.001) and external rotation (p = 0.003) compared with silent hips. Patients with squeaking hips had significantly higher activity levels (p = 0.009). A squeaking hip was not associated with a significant difference in patient satisfaction (p = 0.24) or Harris hip score (p = 0.34). Four implant position factors enabled good prediction of squeaking. These were high acetabular component inclination, high femoral offset, lateralisation of the hip centre and either high or low acetabular component anteversion. This is the largest study to date to examine patient factors and implant position factors that predispose to squeaking of a ceramic-on-ceramic hip. The results suggest that factors which increase the mechanical forces across the hip joint and factors which increase the risk of neck-to-rim impingement, and therefore edge-loading, are those that predispose to squeaking.

Cementless acetabular reconstruction and structural bone-grafting in dysplastic hips. Surgical technique.

BACKGROUND: Studies of acetabular reconstruction with use of cement and bulk bone graft have demonstrated increasing rates of cup failure in patients with dysplastic hips seven years after total hip arthroplasty. Comparable data on the long-term results of bulk bone-grafting done in conjunction with cementless implants are limited. The aim of this study was to review the clinical and radiographic results of autologous bulk bone-grafting in conjunction with a cementless cup. METHODS: From 1987 to 1992, forty-seven patients (forty women and seven men, with an average age of 50.4 years) who had developmental dysplasia of the hip underwent fifty-six total hip arthroplasties and received a structural graft in combination with a cementless Harris-Galante type-I cup. All patients were followed prospectively. In fifty-five hips, implant migration was measured with single-image radiographic analysis. RESULTS: After an average duration (and standard deviation) of 10.2 +/- 2.9 years, three patients (four hips) had died. In the surviving patients, four implants had been revised and two had radiographic evidence of loosening. With use of revision and loosening as end points, the eleven-year survival rates were 91.6% and 88.9%, respectively. Of the fifty implants that had no loosening, fourteen had measurable cup migration, thirty-five had no migration, and one implant could not be measured. All migrations but one were progressive. With loosening used as the end point, the survival rate at eleven years was 100% for the implants with no migration; however, the survival rate for the cups that had migrated was 69.3% (p = 0.0012). CONCLUSIONS: The eleven-year survival rate for the spherical press-fit cups in combination with bulk bone-grafting is satisfactory, given the complexity of these reconstructions. However, the difference between the survival of the implants that had migrated and those that had not was significant. We expect that the thirteen implants with progressive acetabular migration at the time of the latest follow-up are at risk for loosening, which will increase the revision rate for this series in the coming years.

Cementless acetabular reconstruction and structural bone-grafting in dysplastic hips.

BACKGROUND: Studies of acetabular reconstruction with use of cement and bulk bone graft have demonstrated increasing rates of cup failure in patients with dysplastic hips seven years after total hip arthroplasty. Comparable data on the long-term results of bulk bone-grafting done in conjunction with cementless implants are limited. The aim of this study was to review the clinical and radiographic results of autologous bulk bone-grafting in conjunction with a cementless cup. METHODS: From 1987 to 1992, forty-seven patients (forty women and seven men, with an average age of 50.4 years) who had developmental dysplasia of the hip underwent fifty-six total hip arthroplasties and received a structural graft in combination with a cementless Harris-Galante type-I cup. All patients were followed prospectively. In fifty-five hips, implant migration was measured with single-image radiographic analysis. RESULTS: After an average duration (and standard deviation) of 10.2 +/- 2.9 years, three patients (four hips) had died. In the surviving patients, four implants had been revised and two had radiographic evidence of loosening. With use of revision and loosening as end points, the eleven-year survival rates were 91.6% and 88.9%, respectively. Of the fifty implants that had no loosening, fourteen had measurable cup migration, thirty-five had no migration, and one implant could not be measured. All migrations but one were progressive. With loosening used as the end point, the survival rate at eleven years was 100% for the implants with no migration; however, the survival rate for the cups that had migrated was 69.3% (p = 0.0012). CONCLUSIONS: The eleven-year survival rate for the spherical press-fit cups in combination with bulk bone-grafting is satisfactory, given the complexity of these reconstructions. However, the difference between the survival of the implants that had migrated and those that had not was significant. We expect that the thirteen implants with progressive acetabular migration at the time of the latest follow-up are at risk for loosening, which will increase the revision rate for this series in the coming years.

Predicting postoperative morbidity by clinical assessment.

BACKGROUND: The aim of this study was to determine the accuracy of prediction of the surgeon's 'gut-feeling' in estimating postoperative outcome. METHODS: A prospective series of 1077 consecutive patients undergoing major hepatobiliary or gastrointestinal surgery were studied. Patients having elective (n = 827) and emergency (n = 250) procedures were included. The surgeon predicted the development of postoperative complications immediately after completion of surgery on a scale from 0 to 100 percent. These predictions were compared with the actual outcome and with predictions made using the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM). The Portsmouth predictor equation (P-POSSUM) was applied for the estimation of mortality. RESULTS: The observed morbidity and mortality rates were 29.5 and 3.4 percent respectively. POSSUM predicted a morbidity rate of 46.4 percent and P-POSSUM a mortality rate of 6.9 percent. The surgeon's gut-feeling was more accurate in the prediction of morbidity at 32.1 percent. On the basis of gut-feeling, surgeons overpredicted morbidity in elective surgery, but underestimated the risk of complications in the emergency setting. The (P)-POSSUM scoring system overpredicted morbidity and mortality for elective and emergency operations. CONCLUSION: The surgeon's gut-feeling is a good predictor of postoperative outcome, especially after elective surgery. (P)-POSSUM overpredicted morbidity and mortality in this series of major gastrointestinal and hepatobiliary operations.

The effect of cytokine gene polymorphisms on pediatric heart allograft outcome.

BACKGROUND: Cytokines play a major role in the inflammatory and immune responses that mediate allograft outcome. Several studies have shown that the production of cytokines varies among individuals and these variations are determined by genetic polymorphisms, most commonly within the regulatory region of the cytokine gene. The aim of this study was to assess the effect of these allelic variations on acute rejection after pediatric heart transplantation. METHODS: We performed cytokine genotyping using polymerase chain reaction-sequence specific primers in 93 pediatric heart transplant recipients and 29 heart donors for the following functional polymorphisms: tumor necrosis factor-alpha (TNF-alpha) (-308), interleukin (IL)-10 (-1082, -819, and -592), TGF-beta1 (codon 10 and 25), IL-6 (-174), and interferon-gamma (INF-gamma) (+874). The distribution of polymorphisms in this population did not differ from published controls. The patients were classified as either non-rejecters (0 or 1 episode) or rejecters (> 1 episode) based on the number of biopsy proven rejection episodes in the first year after transplantation. RESULTS: Forty-two of the 69 TNF-alpha patients (61%) in the low producer group were non-rejecters, while 9 of the 24 (37.5%) with high TNF-alpha were non-rejecters (p = 0.047). In contrast, IL-10 genotype showed the opposite finding. Forty-two of the 66 patients (64%) in the high and intermediate IL-10 group were non-rejecters, while 9 of the 26 (35%) in the low IL-10 group were non-rejecters (p = 0.011). The combination of low TNF-alpha with a high or intermediate IL-10 genotype was associated with the lowest risk of rejection (34/49 or 69% non-rejecters). Neither the distribution of the IL-6, INF-gamma, and TGF-beta1 genotype in recipients nor the donor genotype showed any association with acute rejection. CONCLUSION: Genetic polymorphisms that have been associated with low TNF-alpha and high IL-10 production are associated with a lower number of acute rejection episodes after pediatric heart transplantation.

The effect of joint loading on acetabular wear measurement in total hip arthroplasty.

All radiographic calculations of acetabular wear assume concentric reduction of the prosthetic articulation. To date, no studies have shown that the femoral head is fully reduced on standard radiographs, and we have seen cases on early postoperative radiographs in which this assumption is not met. Using our computerized radiographic technique, 78 paired anteroposterior pelvic radiographs in 46 patients at a mean of 14 months after surgery (range, 1-92 months) were evaluated with and without joint loading. Displacement with loading was analyzed against time since surgery, a surrogate for acetabular wear. Regression analysis found a statistically significant increase in femoral head displacement after loading with longer duration of follow-up, but the rate of this increase was small (0.027 mm/y). This difference affects calculated wear values by <15%. We conclude that in a low-wear cohort, joint loading does not affect radiographic calculations of acetabular polyethylene wear in a clinically important way.

Determination of polyethylene wear in total hip replacements with use of digital radiographs.

UNLABELLED: We describe a computer-assisted vector wear technique for the determination of polyethylene wear on digital radiographs. Twenty-five hips that had had a total hip arthroplasty were used to evaluate the repeatability and performance of three radiographic techniques to measure wear of the acetabular polyethylene liner: the manual technique with use of calipers described by Livermore et al., the same technique with use of a digitizing tablet, and our new technique of computer-assisted vector wear analysis. We found our new technique to be at least ten times more repeatable than the technique with use of either calipers or a digitizing tablet. Fourteen of the polyethylene liners were retrieved at autopsy, and the actual measurements of wear of those liners were compared with the measurements that had been obtained with the three radiographic techniques of wear analysis. Computer-assisted vector wear analysis outperformed the manual techniques of Livermore et al. When compared with the data obtained from the specimens retrieved at autopsy, the measurement of wear determined with the computer-assisted technique differed by an average of 0.08 millimeter, whereas the measurements obtained with use of calipers and use of a digitizing tablet differed by 0.26 and 0.25 millimeter, respectively. The performance of computer-assisted vector wear analysis in the clinical setting was evaluated with use of controls with known amounts of wear. These were mounted in pelvic phantoms, and radiographs were made with use of a setup that simulated the clinical setting. Analysis of nine controls with 2.0 millimeters of wear yielded an average measurement of wear (and a standard deviation) of 1.99 +/- 0.21 millimeters. CLINICAL RELEVANCE: Computer-assisted vector wear analysis demonstrated superior repeatability and accuracy compared with current techniques of manual analysis. Improved repeatability and accuracy in the determination of polyethylene wear should facilitate the investigation of factors related to the prosthesis and to the patient that affect the rates of wear.

Clostridial gas gangrene of the abdominal wall after laparoscopic cholecystectomy.

Laparoscopic cholecystectomy is associated with a considerable rate of infectious complications of up to 2.8%. Such infections are usually of minor clinical importance. However, we observed a case of life-threatening Clostridial gas gangrene centering around the right lateral port site and developing across all of the right-sided abdominal wall, causing septic shock and severe multi-organ failure. Considering the overall infection rate and the possibility of even severe morbidity, we advocate perioperative antibiotics in laparoscopic cholecystectomy.

Mecanismos inmunológicos de la inmunoterapia específica y controversias sobre su uso / Immunological mechanism of specific immunotherapy and controversy about its utilization

Recientemente han aparecido varios reportes contradictorios acerca del uso de la inmunoterapia específica para el tratamiento de las enfermedades alérgicas. Algunos estudios ponen en duda su eficacia y sus mecanismos de acción. En esta revisión se exponen los datos más recientes que se encuentran en la literatura acerca de los mecanismos inmunológicos que sustentan el buen manejo de la inmunoterapia y los estudios clínicos que encuentran buenos resultados clínicos con su uso. Finalmente exponemos algunos puntos interesantes que surgieron recientemente en esta controversia sobre el uso de inmunoterapia específica en asma y los comentarios que han aparecido en la literatura mundial

Assessing risk in liver transplantation. Special reference to the significance of a positive cytotoxic crossmatch.

OBJECTIVE: The authors determined the impact of a positive cytotoxic crossmatch on the outcome of liver transplantation. SUMMARY BACKGROUND DATA: Liver allografts rarely undergo hyperacute rejection, but transplants performed across a positive cytotoxic crossmatch tend to follow a different clinical course, with higher intraoperative blood use, postoperative graft dysfunction, and, in some cases, graft loss. How this affects overall graft survival has not been determined. METHODS: The authors provide a retrospective analysis of 1520 liver transplants performed between November 1989 and December 1993, with a minimum follow-up of 1 year. All cases had a cytotoxic crossmatch using serum pretreated with dithiothreitol. RESULTS: There were 1390 negative crossmatch and 130 positive crossmatch cases. There was no difference in overall graft survival, although early survival rates were lower in the positive crossmatch group, with the maximum difference at 6 months: 0.76 (95% confidence interval, 0.74-0.78) for a negative crossmatch versus 0.68 (95% confidence interval, 0.61-0.77) for a positive crossmatch. These differences become negligible by the 2-year mark. Using stepwise logistic regression, the authors identified seven variables independently associated with outcome: 1) donor age, 2) donor gender, 3) prior liver transplant, 4) medical urgency status, 5) ischemia time, 6) indication for transplantation, and 7) primary immunosuppressant. CONCLUSIONS: The cytotoxic crossmatch is not statistically associated with overall graft survival after liver transplantation. However, early failure rates are higher in the positive crossmatch cases, a difference that disappears by the second year.

Survival up to 5 and 10 years of mexican pediatric patients with systemic lupus erythematosus. Overhaul of 23 years experience.

A retrospective overhaul of all the patients with Systemic Lupus Erythematosus, deceased or followed-up for at least 5 years within the Immunology Service of the Instituto Nacional de Pediatría (Mexico), since 1970 up to december 1993. The objective was to determine overlife of mexican childs attended in a govermental institution and secondary to get information about demographic characteristics, time from inicial manifestations to diagnosis, treatment received, frequent complications, most important sequelas, and deed causes. 65 clinical records were reviewed, 86.2% females and 13.8% males, ages from 2 to 18 years old; 20 months was the average from start of illnes to definitive diagnosis. Most patient's initial treatment was prednisone and cyclophosphamide, being modified according to response evaluated by clinical al laboratory follow-up. Fifty one patients (78.5%) survived, 60% from 5 to 10 years, and 40% more than 10 years. Fourteen patients died (21.5%). Most frequent complications were local and systemic infections, hemorragic cystitis and steroidal diabetes. Principal dead cause was sepsis. Mortality en Systemic Lupus Erythematosus patients continues being high. Many factors contribute for delay diagnosis, in its way responsable for poorer pronostic. As a pediatric hospital, follow-up is end at adulthood, what makes long term follow-up limited.

[Transversal myelitis as initial manifestation of secondary antiphospholipid syndrome. Report of a case]. / Mielitis transversa como manifestación inicial del síndrome antifosfolípido secundario. Informe de un caso.

We report the clinical case of an 8 years female with systemic lupus erythematosous who developed transverse myelitis secondary to antiphospholipid syndrome. She had an excellent response to the treatment with Prednisone and Cyclophosphamide. As long as we know this is the first report of transverse myelitis as clinical manifestation of antiphospholipid syndrome in childhood.

Physiological augmentation of amino acid-induced insulin secretion by GIP and GLP-I but not by CCK-8.

It was the aim of this study to test insulinotropic actions of cholecystokinin octapeptide (CCK-8), gastric inhibitory polypeptide (GIP), and glucagon-like peptide I (GLP-I)-(7--36) amide at basal glucose but physiologically elevated amino acid concentrations. Therefore, in nine fasting healthy volunteers, an amino acid mixture was infused intravenously (12.6 g/h over 120 min). On separate occasions, from 30 to 120 min, placebo (0.9% NaCl-1% human serum albumin), synthetic sulfated CCK-8 (0.5 pmol.kg-1.min-1), human GIP (1 pmol.kg-1.min-1), or GLP-I-(7--36) amide (0.3 pmol.kg-1.min-1) was infused intravenously to mimic physiological increments after a meal. The amino acid infusion lead to a small increment in plasma glucose from 4.8 +/- 0.2 to 5.0 +/- 0.2 mmol/l and significantly elevated insulin and C-peptide concentrations. GIP and GLP-I-(7--36) amide further stimulated insulin (1.8-fold, P = 0.0001 and 0.004, respectively) and C-peptide (1.3-fold, P = 0.0003 and 0.013, respectively), with a subsequent slight reduction in plasma glucose (P < 0.0001). Insulin and C-peptide then decreased again in parallel. CCK-8 was without effect on insulin and C-peptide levels. In conclusion, GIP and GLP-I-(7--36) amide are not only able to interact with elevated plasma glucose but are insulinotropic also with physiologically raised amino acid concentrations. Such an interaction could play a role after the ingestion of mixed meals. Cholecystokinin, on the other hand, is not a physiological incretin also under these conditions.

Total hip replacement with insertion of an acetabular component without cement and a femoral component with cement. Four to seven-year results.

One hundred and fifty-three so-called hybrid total hip replacements were performed in 142 patients from 1985 to 1987 at Rush-Presbyterian-St. Luke's Medical Center. A hemispherical porous-coated acetabular component was inserted without cement and was fixed with screws, and a femoral stem was inserted with the use of so-called third-generation cementing techniques. The average age of the patients at the time of the operation was sixty-seven years (range, thirty-nine to eighty-five years). The average preoperative Harris hip score was 46 points (range, 9 to 73 points). One hundred and eleven patients (120 hips) were available for clinical review; 100 of these patients (109 hips) had a complete set of radiographs available. The average Harris hip score was 86 points (range, 29 to 100 points) at the time of follow-up (average duration, sixty-two months; range, forty-eight to eighty-five months). There was progressive migration of one cup (1 per cent); another cup migrated one centimeter in the first two years after the operation, with no additional migration evident after that time. The remaining acetabular components were stable. Two femoral components (2 per cent) were determined to be definitely loose. The remaining femoral components were stable. This population of patients had a good result after so-called hybrid total hip replacement with insertion of a porous-coated acetabular component without cement and a femoral component with cement for the reconstruction of a painful hip.

Primary total hip reconstruction with a titanium fiber-coated prosthesis inserted without cement.

A prospective study was done of the intermediate-term clinical and radiographic results of 121 total hip arthroplasties in which a Harris-Galante porous titanium-fiber-coated prosthesis was inserted without cement in 110 patients. The average age at the time of the operation was forty-nine years (range, twenty to seventy years). The average duration of follow-up was sixty-seven months (range, fifty-five to seventy-nine months). The average preoperative Harris hip score was 55 points, and the average postoperative score was 93 points. One acetabular component was revised due to recurrent dislocation. Eleven femoral implants were unstable, and of these, four were revised. Cortical erosion was present around the distal part of the femoral stem in nine patients (8 per cent) who had stable implants, and one of these femoral implants was revised because the erosion was extensive. Survivorship analysis at five years revealed a 97 per cent chance of survival (95 per cent confidence limit, 0.937 to 1.0) of the Harris-Galante femoral-stem implant inserted without cement.

Clinical experience with primary cementless total hip arthroplasty.

One hundred-eleven patients (121 hips) treated with cementless total hip arthroplasty (Harris-Galante, Zimmer) were clinically and radiographically reviewed at an average follow-up of 67 months (55-79). 9,1% of the stems presented signs of loosening and 5 stems (4,1%) had to be revised. None of the acetabula required revision surgery for loosening. One socket was revised due to recurrent dislocation. Clinical results were evaluated according to Harris protocol: excellent 75,2%, good 12,4%, fair 5%, poor 3,3%. Ten (7,9%) intraoperative fractures of the proximal femur were observed: in 2 cases stem instability consequently occurred. Endosteal cortical erosions, not clinically evident, were observed in 8,3% of stable stems. A foreign body biological reaction to polyethylene or metallic debris is supposed as cause of erosions.

Cementless Gustilo-Kyle and BIAS total hip arthroplasty: 2- to 5-year results.

We conducted extensive radiographic and clinical examination of 58 cementless total hip arthroplasties. Forty BIAS femoral stems had heads made of Co-base F 75 alloy and 18 Gustilo-Kyle femoral stems had Ti6A14V alloy heads. The cross-sectional geometry and location of the porous coating pads of the two stem types was identical, the BIAS component being slightly shorter. At the last follow-up, 27.8% of the Gustilo-Kyle femoral components and 2.5% of the BIAS femoral components were unstable. None of the acetabular components in the BIAS group as against 38.9% of the acetabular components in the Gustilo-Kyle group demonstrated wear of more than 1 mm. All unstable components which did not suffer intraoperative fracture had also acetabular wear of more than 1 mm. The only case with endosteal erosion was seen in a patient with an unstable implant displaying the most extensive wear. Nonparametric statistical analysis showed that the patients with Ti6A14V/polyethylene bearing surfaces had a statistically significantly higher extent of wear and a statistically significant higher incidence of femoral component loosening than patients with CrCoMo/polyethylene bearing surfaces.

T and Tk transformation in hemolytic uremic syndromes.

In two cases of hemolytic uremic syndrome (HUS) the bacterial pathogenesis of the disease could be elucidated by lectin red cell agglutination tests. The possible role of anti-T and anti-Tk antibodies is discussed. Transfusions of fresh plasma had no adverse effects. The fatal outcome in one case was caused by disseminated intravascular coagulation (DIC).