Abnormal US appearance of the cerebellum (banana sign): indirect sign of spina bifida

Certain fetal cranial abnormalities found on second-trimester sonograms can be signs of an open spina bifida. In particular, an abnormal configuration of the cerebellum, known as the banana sign, has been associated with neural tube defects. To further evaluate the usefulness of this sign, the authors compared images of the posterior fossa in 23 fetuses who had documented neural tube defects with those of 38 control fetuses who underwent sonography because of an elevated maternal serum alpha-fetoprotein level. Twenty-two of the 23 fetuses with neural tube defects had compression and anterior alignment of the cerebellar hemispheres (the banana sign), and follow-up confirmed the presence of an open neural tube defect. One fetus had a normal-appearing posterior fossa; however, the neural tube defect at birth was completely covered with skin. Four of the neural tube defects were difficult to see sonographically, and the abnormal configuration of the cerebellum, as well as the flattening of the frontal bone (lemon sign), was instrumental in suggesting the correct diagnosis. The 38 control fetuses had normal-appearing posterior fossae.     

Early amniocentesis for prenatal cytogenetic evaluation

Early amniocentesis at 11-14 weeks gestation was evaluated in 100 consecutive patients to see how this technique compares with later amniocentesis. There were no complications as a consequence of the procedure or related pregnancy losses of chromosomally normal fetuses. Samples obtained from three (3%) patients showed insufficient cell growth; two of these patients elected a repeat procedure, which yielded a normal karyotype in each case. There were five abnormal karyotypes, one of which was a culture artifact; in the latter case, repeat amniocentesis at 15 weeks yielded a normal result. Of the 95 pregnancies with normal karyotypes, 94 were progressing normally at follow-up, and one patient elected pregnancy termination because of maternal indications. It appears that early amniocentesis may be an attractive alternative to traditional amniocentesis, in that it provides results at an earlier gestational age and may avoid certain disadvantages of chorionic villus sampling.     

Predictors of incident atrial fibrillation and influence of medications: a retrospective case�Ccontrol study

Background

Atrial fibrillation (AF) is a common condition, associated with raisedmortality and risk of majormorbidity, and is predicted to increase due to an aging population.

Aim

To update earlier research of AF predictors using UK data.

Design and setting

Case–control analysis of adults aged 18 years and older with a diagnosis of AF in practices registered with the General Practice Research Database (GPRD) in the UK.

Method

Using the GPRD, a case.control analysis was performed using logistic regression to compare 55 412 incident AF cases to 216 400 controls, for medical history and prior use of drugs. The association between time since start of diagnosis or drug use and AF risk was summarised using Spline regression.

Results

The following were confirmed as risk factors for AF: heart failure (risk ratio [RR] 2.91 [95% CI = 2.59 to 3.27]); ischaemic heart disease (IHD) (RR 2.00 [95% CI = 1.78 to 2.24]); hypertension (RR 2.60 [95% CI = 2.32 to 2.92]); hyperthyroidism (RR 1.56 [95% CI = 1.39 to 1.75]); being a heavy drinker (RR 1.43 [95% CI = 1.27 to 1.60]); cerebrovascular accident (RR 1.48 [95% CI = 1.32 to 1.66]); and obesity (bodymass index ≥30 kg/m² RR 1.29 [95% CI = 1.15 to 1.45]). Current use of oral glucocorticoids (RR 1.62 [95% CI = 1.44 to 1.82]) and of beta-2 agonists (RR 1.30 [95% CI = 1.16 to 1.46]) were identified as significant risk factors, and statins (RR 0.82 [95% CI = 0.73 to 0.92]) as a significant protective factor. No effect was found for current use of bisphosphonates (RR 0.95 [95% CI = 0.85 to 1.07]), renin.angiotensin.aldosterone system (RAAS) agents (RR 1.04 [95% CI = 0.93 to 1.17]), or xanthine derivatives (RR 1.09 [95% CI = 0.97 to 1.22]). Spline regression analysis found the effect of heart failure, IHD, use of oral glucocorticoids, and use of statins on the likelihood of developing AF was sustained over a number of years.

Conclusion

These findings update the risk factors that are associated with AF, and confirmthe protective properties of statins and the risks of beta-2 agonists in developing AF, but not the supposed protective qualities of glucocorticoids and RAAS agents.     

Increased radiosensitivity of a subpopulation ot T-lymphocyte progenitors from patients with Fanconi's anemia

In vitro radiation survival of peripheral blood T lymphocytes was studied in 15 clinically normal adults and 4 patients with Fanconi's anemia. Tritiated thymidine incorporation in a whole blood lymphocyte stimulation test (LST) and a newly developed whole blood T-lymphocyte colony assay were used to measure lymphocyte blastogenesis and colony formation in response to phytohemagglutinin (PHA) or concanavalin-A (Con-A) stimulation. Lymphocyte colony formation was found to be consistently more sensitive than the LST for detection of low-level radiation effects using both normal cells and lymphocytes from Fanconi's anemia patients. Lymphocytes from patients with Fanconi's anemia were significantly more sensitive to in vitro x-irradiation than lymphocytes from clinically normal individuals as measured by their ability to divide when stimulated by PHA in the LST (patients, D37 = 198 R; normals, D37 = 309 R, p = 0.057) and colony formation assay (patients, D37 = 53 R; normals, D37 = 109 R, p = 0.016). No significant difference in the radiosensitivity of the Con-A response was observed between the two groups. The PHA-responsive T-lymphocyte subpopulation in Fanconi's anemia patients appears to be intrinsically defective. The nature of this defect, significance in the disease process, and relevancy of these findings to the establishment of radiation protection standards are discussed.     

Low dose short duration pulsed electromagnetic field effects on cultured human chondrocytes: An experimental study

Background:

Pulsed electromagnetic field (PEMF) is used to treat bone and joint disorders for over 30 years. Recent studies demonstrate a significant effect of PEMF on bone and cartilage proliferation, differentiation, synthesis of extracellular matrix (ECM) and production of growth factors. The aim of this study is to assess if PEMF of low frequency, ultralow field strength and short time exposure have beneficial effects on in-vitro cultured human chondrocytes.

Materials and Methods:

Primary human chondrocytes cultures were established using articular cartilage obtained from knee joint during joint replacement surgery. Post characterization, the cells were exposed to PEMF at frequencies ranging from 0.1 to 10 Hz and field intensities ranging from 0.65 to 1.95 μT for 60 min/day for 3 consecutive days to analyze the viability, ECM component synthesis, proliferation and morphology related changes post exposure. Association between exposure doses and cellular effects were analyzed with paired''t’ test.

Results:

In-vitro PEMF exposure of 0.1 Hz frequency, 1.95 μT and duration of 60 min/day for 3 consecutive days produced the most favorable response on chondrocytes viability (P < 0.001), ECM component production (P < 0.001) and multiplication. Exposure of identical chondrocyte cultures to PEMFs of 0.65 μT field intensity at 1 Hz frequency resulted in less significant response. Exposure to 1.3 μT PEMFs at 10 Hz frequency does not show any significant effects in different analytical parameters.

Conclusions:

Short duration PEMF exposure may represent a new therapy for patients with Osteoarthritis (OA).     

Urethral cultures in patients with spinal cord injury

STUDY DESIGN: Prospective analysis. OBJECTIVES: To investigate the colonization of the distal urethra and bladder during the initial stages of rehabilitation in acute spinal-cord injury (SCI) and to examine the association between bacteriuria and colonization of the distal urethra. SETTING: Selcuk University Meram Faculty of Medicine, Konya, Turkey. METHODS: A total of 27 patients with SCI (13 females and 14 males) and 40 controls without evidence of disease of the urinary tract were studied. Cultures were taken from the patients who applied clean intermittent catheterization and compared with normal subjects. RESULTS: Escherichia coli was predominantly isolated from the urine and urethral cultures of both female and male SCI patients. Colonization of other bacteria in the urine and urethral cultures was similar in both female and male patients, except for Pseudomonas, which was colonized in male patients. In all, 72% of patients who had E. coli positive urethral cultures also had E. coli colonization in their simultaneous urine cultures. There was concordance between urethra and urine cultures concerning the growth of E. coli (P=0.82). When urethral cultures collected 1 week before were evaluated in patients with E. coli positive urine cultures (n=24 cultures), 15 of these urethral cultures also had E. coli colonization. There was concordance between urethra and urine cultures concerning the growth of E. coli (P=0.66). CONCLUSIONS: Our study suggested that urethral flora was a significant source for the development of urinary infection in spinal cord-injured patients.     

Experimental autoimmune myasthenia gravis induction in B cell-deficient mice

Experimental autoimmune myasthenia gravis (EAMG) is an animal model for human myasthenia gravis (MG). Autoantibody-induced functional loss of nicotinic acetylcholine receptor (AChR) at the postsynaptic membrane is an important pathogenic feature of both MG and EAMG. To evaluate the extent at which the humoral immune response against AChR operates in the pathogenesis of EAMG, we immunized B cell knockout (muMT) and wild- type C57BL/6 mice with AChR and complete Freund's adjuvant. The ability of AChR-primed lymph node cells to proliferate and secrete IFN-gamma in response to AChR and its dominant peptide alpha146-162 were intact in muMT mice as in wild-type mice. Similar amounts of mRNA for IFN-gamma, IL-4 and IL-10 in AChR-reactive lymph node cells were detected in muMT and wild-type mice. However, muMT mice had no detectable anti-AChR antibodies and remained completely free from clinical EAMG. We conclude that B cells are critically required for the genesis of clinical EAMG, but not for AChR-specific T cell priming.      

Diagnostic imaging of human neuroblastoma with radiolabeled antibody

In a previous study, the authors showed that iodine-131 labeled monoclonal antibody (Mab 3F8) could be used to image human neuroblastoma xenografts in mice with excellent tumor-to-tissue ratios. In this study they report their experience with six patients scanned with radiolabeled 3F8. There was strong accumulation of the labeled antibody in viable tumor, but no significant uptake was noted in normal brain, liver, spleen, or adrenal glands. Tumor-to-nontumor activity ratios varied but were approximately 10:1-20:1. This ratio yields good contrast for visualization. Time-activity curves show that radioactivity levels in normal tissue have a half-time of about 40 hours, whereas tumor tissues show a half-time of about 60 hours. Significant gastric secretion of free iodine demonstrated that the Mab was being deiodinated. Calculated radiation doses indicate that tumors receive at least ten times the dose to other tissues. The results indicate that Mab 3F8 has clinical potential for both imaging and therapy of human neuroblastomas.