Densitometer type and impact on risk assessment for osteoporosis.

Studies have shown a high correlation between measurements of bone mineral density (BMD) obtained on differentdual-energy X-ray absorptiometry machines. Challenger osteodensitometers (Diagnostic Medical System [DMS],Montpellier, France) are becoming widely used but little is known about their clinical performance. The aim of this study was to compare BMD measurements and the resulting patient classification based on T-scores obtained on a DMS Challenger device to those obtained on Hologic 4500A (Bedford, MA) device. Fifty-three volunteers were studied.The BMD of the spine and of the hip were simultaneously measured on both densitometers. BMD values obtained on the Challenger were significantly higher than those obtained with the Hologic QDR4500 (p<0.001). The correlations coefficients between the Hologic QDR4500 and the DMS Challenger measured BMDs were r=0.70 at the femoral neck, r=0.70 at the trochanter, and r=0.83 at the spine (p<0.001). Among the 35 postmenopausal women, there was discordance in the WHO T-score-based classification in 28 subjects (80%) at the spine, 18 subjects (52%) at the femoral neck, and 14 subjects (42%) at the trochanter. The intermachine agreement was low: The kappa score was -0.10 at the spine, 0.2 at the femoral neck, and 0.3 at the trochanter. In conclusion, this study cautions against the use of non established densitometers that leads to underdiagnosis of patients and, subsequently, to inappropriate treatment strategies.     

Dual-energy x-ray absorptiometry of the forearm: reproducibility and correlation with single-photon absorptiometry.

Although single-photon absorptiometry (SPA) has been the predominant tool used to assess bone mineral density (BMD) in the forearm, the development of dual-energy x-ray absorptiometry (DEXA) provides the benefits of greater source stability, reduced scanning time, and improved image resolution compared to SPA. In the present study we used the DEXA bone densitometer (Hologic, Inc., Waltham, MA) to (1) measure BMD in the one-third radius and ultradistal radius; (2) examine the reproducibility of these BMD measurements; and (3) compare the BMD at the one-third radius with SPA (SP2, Lunar Corp., Madison, WI). In 65 normal women (ages 22-74 years) we examined changes in the forearm DEXA BMD with age, revealing significant quadratic regression equations. The reproducibility of DEXA BMD (mean +/- SEM) in 7 normal subjects aged 22-50 years is 0.85 +/- 0.16% for the predominantly cortical one-third radius site and 0.97 +/- 0.15% for the more trabecular ultradistal site. The regression relationship between DEXA and SPA of the one-third radius in 26 subjects (ages 22-68 years) is DEXA BMD = 0.105 + 0.826 (SPA BMD); R = 0.97, R2 = 0.94, p less than 0.0001. Bone densitometry of the forearm using DEXA may be performed relatively rapidly, providing reproducibility and image resolution that are generally superior to those observed with SPA.     

Successful replantation of amputated nose and auricle

Amputations of the nose and of the auricle present difficult management problems. Application of simple reattachment techniques, followed by aggressive medical therapy which consists of cooling, anticoagulation, antibiotic coverage, and multiple stab incisions in the amputated tissues, have resulted in the successful replantation of major portions of an amputated nose and an amputated auricle with satisfactory cosmetic results.     

Rosai-Dorfman Disease: A previously unreported association with Sickle Cell Disease

Background  

Rosai-Dorfman Disease is an uncommon benign systemic histio-proliferative disease. This is the first time the disease, although more common in people of African descent, is described in association with Sickle cell disease.     

Human papillomavirus infection in Egyptian esophageal carcinoma: correlation with p53, p21, mdm2, C-erbB2 and impact on survival

The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21(waf), c-erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21(waf)and c-erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c-erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21(waf) was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c-erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21(waf). Human papillomavirus infection is frequent in Egyptian EC. Both p53-dependent and p53-independent pathways seem to be involved in HPV-associated EC. mdm2 and c-erbB2 are possible targets for HPV in the p53-independent pathway. However, only advanced stage and aberrant expression of p53 and p21(waf) are independent prognostic markers.     

REM sleep deprivation inhibits LTP in vivo in area CA1 of rat hippocampus

Rapid eye movement (REM) sleep deprivation has previously been shown to interfere with normal learning and memory and to inhibit long-term potentiation (LTP) in vitro. Previous studies on REM sleep deprivation and LTP have relied on in vitro analysis in isolated brain slices taken from animals following several days of sleep deprivation. LTP in the hippocampus in situ may differ from LTP in vitro due to modulatory inputs from other brain regions, which are altered after REM sleep deprivation. Here, we examined LTP in unanesthetized, behaving animals on the first and second recovery days following REM sleep deprivation to determine if similar effects are seen in vivo as previously reported in vitro. We found that LTP was significantly impaired in REM sleep-deprived animals on the second recovery day but not the first recovery day. Our results extend previous findings by showing that REM sleep deprivation continues to affect hippocampal function for more than 24h following the end of deprivation. Our results also suggest the presence of a modulatory process not present in vitro. Our findings are not explained by stress during REM sleep deprivation because equivalent circulating corticosterone levels (an index of stress) were found during both REM sleep deprivation and control treatment.     

Deletions in the ligand for CD40 in X-linked immunoglobulin deficiency with normal or elevated IgM (HIGMX-1)

Patients with X-linked Ig deficiency with normal or elevatedIgM (HIGMX-1) fail to switch from IgM/IgD to other Ig isotypes.Interaction between the B cell antigen CD40 and the CD40 ligandexpressed on activated T cells is critical for T cell drivenisotype switching. We have reported that T lymphocytes fromthree unrelated male patients with HIGMX-1 failed to expressCD40 ligand on their surface, but the mRNA for CD40 ligand wasof an apparently normal size and level. Analysis of CD40 ligandcDNA from two of the patients revealed deletions that alterthe reading frame. Patient 1 displayed two mutations: a C Atransversion at nucleotide 590 and the deletion of an adjacentC nucleotide. The second patient had a 58 bp deletion from nucleotides289–346. Furthermore, neither patient expressed a proteinproduct detectable by the CD40L mAb, 5c8.     

Finite Element Analysis of Self-Healing Concrete Beams Using Bacteria

Deterioration or crack formation in concrete elements is a phenomenon that cannot be easily avoided, and it has a high cost of repair. A modern technology that needs wider study is the use of the bio-precipitation of calcium carbonate using bacteria to increase a structures’ capacity. The current research presents an analytical study on self-healing concrete beams using bacteria to enhance the beam’s capacity. A Finite Element Analysis on (ANSYS 15.0) was carried out to study the effect of the bacteria concentration (the weight of bacteria to cement weight 1%, 2%, and 3%), the type of bacteria (Bacillus subtilis, E. coli, and Pseudomonas sps.), and the loading (a one-point load, a two-point load, and a distributed load on four points) on concrete beams. Two beams were chosen from previous experimental research and simulated on the ANSYS before carrying out our parametric study to verify the validity of our simulation. Following this, our parametric study was carried out on eight beams; each beam was loaded gradually up to failure. The results show that the optimum type of bacteria was the Bacillus subtilis, and that the bacteria concentration of 3% for Bacillus subtilis can increase the beam’s capacity by 20.2%. Also, we found that distributing the load to four points led to the increase of the beam’s capacity by 74.5% more than the beam with a one-point load.     

Uxoricide by a schizophrenic patient with delusional misidentification syndromes: A case report

Delusional misidentification syndromes in psychiatric disorders might result in dangerous behavior leading sometimes to homicide. An early diagnosis and thorough follow up is important to avoid such consequences.