Factors affecting early versus late remission in acromegaly following stereotactic radiosurgery

Journal of Neuro-Oncology - Stereotactic radiosurgery (SRS) is a well-established treatment modality for patients with acromegaly. Our previously published study demonstrated a median time to...     

Education is associated with reduction in racial disparities in kidney transplant outcome

In this study, we hypothesized that higher level of education might be associated with reduced racial disparities in renal transplantation outcomes. We used data from the United States Renal Data System (September 1, 1990–September 1, 2007) (n = 79 223) and analyzed two outcomes, graft loss and recipient mortality, using Cox models. Compared with whites, African Americans had increased risk of graft failure (HR, 1.48; p < 0.001) and recipient mortality (HR, 1.06; p = 0.004). Compared with recipients who graduated from college, all other education groups had inferior graft survival. Specifically, compared with college‐graduated individuals, African Americans who never finished high school had the highest risk of graft failure (HR, 1.45; p < 0.001), followed by high school graduates (HR, 1.27; p < 0.001) and those with some college education (HR, 1.18; p < 0.001). A similar trend was observed in whites. In African Americans (compared with whites), the highest risk of graft failure was associated with individuals who did not complete high school (HR, 1.96; p < 0.001) followed by high school graduates (HR, 1.47; p < 0.001), individuals with some college education (HR, 1.45; p < 0.001), and college graduates (HR, 1.39; p < 0.001). A similar trend was observed with recipient mortality. In sum, higher education was associated with reduced racial disparities in graft and recipient survival.     

Finite Element Analysis: A Maxillofacial Surgeon’s Perspective

The science of finite element analysis (FEA) is purely a mathematical way of solving complex problems in the universe. In medical field, this is an innovation in biomedical research and development, as it gives easier mathematical solution to biological problems. This article deals with the understanding of various basic material properties of bone like Young’s modulus, yield strength, Bulk modulus, shear modulus, Poisson’s ratio and density from a maxillofacial surgeon’s perspective. Basic concepts in FEA, its application, advantages, disadvantages, and limitations in the field of maxillofacial surgery have been discussed. The importance of surgical fraternity to be in coordination with evolving technologies has been emphasized for the future of evidence based practice of oral and maxillofacial surgery.     

A study on coronal incision for treating zygomatic complex fractures

Objective  To study the value of coronal incisions for treating zygomatic complex fractures and evaluate the advantages, indications and complications associated with it. Method  In this prospective study, 12 patients were randomly selected regardless of age, sex requiring open reduction and internal fixation of communited zygomatic complex fractures with or without other associated fractures of the midface. Patients were all treated by coronal approach for open reduction and internal fixation of fracture of the zygomatic complex. Other local incisions were used if required. Results  In all cases postoperative complications were relatively minor except in one case were the temporal branch of facial nerve weakness persisted at 3 months. Whereas 5 cases reported with slight weakness of the temporal branch of the facial nerve which resolved at the end of 3 months. The time taken for exposure of the fracture site via the coronal incision had a mean of 28.7 minutes. There were no cases of flap infection and just 1 case of stitch abscess reported. The same case later reported with a hypertrophic scar formation of greater than 0.5cm at 3months. In all other cases scar formation was negligible and well hidden within the hairline. There were no reported cases of paraesthesia at the operated site or hollowing of the temporal fossa. Conclusion  The coronal incision provides excellent access to the zygomatic arch and zygomatic complex, aiding in good anatomical reduction and also has the added advantage of the scar hidden in the hairline. It also has disadvantages like long operating time, risk of facial nerve injury, scarring in patients with male pattern baldness, paraesthesia of operated site etc. Therefore the incision should be judiciously used and not overused and indications strictly applied.     

Cyclooxygenase-2 is Upregulated in Copper-Deficient Rats

Copper deficiency inactivates Cu/Zn-SOD and promotes accumulation of reactive oxygen species. This process likely impairs nitric oxide (NO)-mediated relaxation as well as triggers vascular inflammation. The current study was designed to determine whether COX-2, a proinflammatory protein, expression and activity are upregulated in the oxidative environment associated with inadequate Cu. Weanling male Sprague Dawley rats were fed purified diets which were either Cu-adequate (Cu-A); Cu-marginal (Cu-M), Cu-deficient (Cu-D), or the Cu-D diet combined with the SOD mimetic Tempol (Cu-D/T; 1 mM in drinking water) for 4 weeks. COX-2 protein, PGE₂ (COX-2 metabolite) and isoprostanes (index of oxidative stress) were all higher in the Cu-D group vs Cu-A group, but no significant differences occurred between the Cu-M and Cu-A groups. Tempol protected against an attenuation of NO-mediated vasodilation in the Cu-D rats but did not prevent the elevation of PGE₂ or isoprostanes. Our data suggest a role for copper as a modulator of oxidative stress and inflammation independent of SOD activity or NO-derived oxidants.     

Admission hyperglycemia as a prognostic indicator in trauma

OBJECTIVE: The purpose of this study was to assess the utility of two levels of hyperglycemia as predictors for mortality and infectious morbidity in traumatically injured patients. METHODS: All patients >or= 17 years old presenting to a Level I trauma center as a "trauma alert" or a "trauma code" from January 1, 2000, through December 31, 2000, were reviewed. Hypoglycemic patients (glucose concentration < 70 mg/dL) were excluded (n = 4). Patients were considered hyperglycemic with an admission glucose concentration > 200 mg/dL (moderate hyperglycemia) or an admission glucose concentration in the upper quartile for the group (mild hyperglycemia [glucose concentration > 135 mg/dL]). RESULTS: Seven hundred thirty-eight patients were included in the study. Hyperglycemia was associated with increased mortality among both patients with moderate hyperglycemia (34.1% vs. 3.7%, p < 0.01) and those with mild hyperglycemia (15.5% vs. 2%, p < 0.01) compared with corresponding normoglycemic groups. Hyperglycemia proved to be an independent predictor of mortality and of hospital and intensive care unit length of stay after multiple logistic regression while controlling for age, Injury Severity Score, Revised Trauma Score, and gender. Infectious complications, including pneumonia (9.4% vs. 2%, p = 0.001), urinary tract infections (6.6% vs. 1.4%, p = 0.001), wound infections (4.9% vs. 0.6%, p = 0.039), and bacteremia (5% vs. 1.1%, p = 0.004), were significantly increased in patients with elevated glucose concentrations. Hyperglycemia is an independent predictor of increased infectious morbidity controlling for age, gender, and Injury Severity Score in multiple logistic regression models. CONCLUSION: Hyperglycemia independently predicts increased intensive care unit and hospital length of stay and mortality in the trauma population. It is associated with increased infectious morbidity. These associations hold true for mild hyperglycemia (glucose concentration > 135 mg/dL) and moderate hyperglycemia (glucose concentration > 200 mg/dL).     

Normal coronary artery dimensions in Indians

Background There is no available data on normal coronary artery size in the Indian population. We attempted to establish a database for normal dimensions of the coronary artery segments during life by using quantitative coronary angiography and compared these with Western estimates of coronary artery size. Material and Methods Between december 2003 and June 2004, 94 patients who underwent quantitative coronary angiography for evaluation of symptoms of ischemic heart disease and were found to have no coronary artery disease form the sample size. Results The dimensions of branches in the left coronary system in our patients were less and those of the distal circumflex, and the proximal and distal left anterior descending coronary arteries were significantly greater than those of Indian Asians living in the United Kingdom and the native Caucasians but the dimensions of the right coronary artery were significantly greater in our patients. Conclusions Coronary artery dimensions for at least some branches of the left coronary system are similar to that reported in the West and the dimensions of the right coronary are greater. These findings contradict the general perception that Indians have smaller coronary arteries.     

Immunogenicity of the Mycobacterium tuberculosis PPE55 (Rv3347c) protein during incipient and clinical tuberculosis

Clinical tuberculosis (TB), whether noncavitary or cavitary, is the late stage of a chronic disease process, since Mycobacterium tuberculosis is a slowly growing organism. Our studies have shown that the profiles of antigenic proteins expressed by the in vivo bacteria that elicit antibodies differ in cavitary and noncavitary TB. To gain insight into antigenic proteins expressed during incipient, subclinical TB, an expression library of M. tuberculosis genomic DNA was screened with sera obtained during subclinical TB from guinea pigs infected with aerosols of M. tuberculosis H37Rv. One of the proteins recognized by antibodies elicited during subclinical TB infection of guinea pigs is the 309-kDa PPE55 (Rv3347c) protein. Genomic hybridization studies suggest that the PPE55 gene is specific to the M. tuberculosis complex and is present in a majority of clinical isolates tested. Antibodies to the C-terminal, approximately 100-kDa fragment of PPE55 (PPE-C) were detectable in sera from 29/30 (97%) human immunodeficiency virus-negative/TB-positive (HIV(-) TB(+)) patients and 17/24 (71%) HIV(+) TB(+) patients tested but not in sera from purified-protein derivative-positive healthy controls, suggesting that the in vivo expression of PPE55 protein correlates with active M. tuberculosis infection. Anti-PPE-C antibodies were also detected in retrospective sera obtained months prior to manifestation of clinical TB from 17/21 (81%) HIV(+) TB(+) individuals tested, providing evidence that the protein is expressed during incipient, subclinical TB in HIV-infected humans. Thus, PPE55 is a highly immunogenic protein that may be useful for differentiating between latent TB and incipient, subclinical TB.