The changing approach to falls in the elderly

The annual incidence of falls is approximately 30 percent in persons over the age of 65 years. The risk of falls is greater in older persons, with the annual incidence increasing to 50 percent in those over age 80. Because of the significant incidence of falls in the elderly, physicians should have an organized approach to fall assessment and prevention. Most falls in the elderly are caused by complex interactions of intrinsic and extrinsic factors. A thorough history is essential to identifying the intrinsic or extrinsic factors involved. Approximately one half of falls in the elderly can be attributed to accidents and extrinsic causes such as slippery floors, and the remainder from intrinsic causes such as lower extremity weakness, gait disorders, effects of medications or acute illness. Extrinsic and intrinsic factors that are identified may be amenable to one of three management approaches: treating acute or reversible deficits, reducing the cumulative burdens of deficits, or using adaptive devices for irreversible deficits. A careful and focused evaluation can identify factors that can be corrected or therapeutic interventions that will lessen the risk of a subsequent fall.     

Peripheral nerve regeneration: the effects of postoperative irradiation

Our purpose is to review recent data and provide a clinical opinion on the use of antibiotics to prevent preterm birth or related maternal-neonatal complications. A literature review and a synthesis of opinion are provided. During prenatal care, standard practices should be applied regarding Neisseria gonorrhoeae, Chlamydia trachomatis, and bacteriuria. In addition, screen for and treat bacterial vaginosis in patients at high risk for preterm birth but do not treat Ureaplasma urealyticum or group B streptococci genital colonization. With preterm labor and intact membranes, standard practices should be applied regarding group B streptococci prophylaxis. Do not give antibiotics routinely to prolong pregnancy, but in patients with bacterial vaginosis and Trichomonas vaginalis specific treatment should be given. With preterm premature rupture of membranes, standard practices should be applied regarding group B streptococci prophylaxis, but additional antibiotics should also be given to prolong pregnancies at 24 to 32 weeks' gestation. Reported adverse effects have been few to date. However, increased diligence is needed for resistant organisms. In selected clinical settings antibiotic therapy is now indicated to prolong pregnancy and prevent maternal-neonatal complications associated with preterm birth.     

Itraconazole maintenance treatment for histoplasmosis in AIDS: a prospective, multicenter trial

The expression of cytokeratins (CKs) in normal cervical epithelium, low grade squamous intraepithelial lesions (SIL), high grade SILs and squamous cell carcinoma (SCC) were analyzed using four different monoclonal antikeratin antibodies. In normal cervical epithelium, CK 18 showed strong immunoreactivity in basal and parabasal layers. CK 19 and 14 were expressed only in the basal layer while CK 13 was found selectively n the spinal cells. As the lesions progressed from low grade SIL to high grade SIL, immunoreactivity of CK 18, 19 and 14 in the basal cell compartment increased while the expression of CK 13 decreased. In SCC, as well-differentiated tumors showed decreased immunoreactivity for CK 18, 19 and 14 with CK 13 showing a strong and focal (localized) immunoreactivity. Undifferentiated carcinomas totally lacked CK 13 reactivity. Our findings therefore suggest that expression of CK 18, 19 and 14 may be directly related to tumor grade and CK 13 may be a marker of differentiation in cervical lesions.     

Striatal and extrastriatal imaging of dopamine D2 receptors in the living human brain with [123I]epidepride single-photon emission tomography

The complete sequence of a 36775 bp DNA segment located on the right arm of chromosome XV of Saccharomyces cerevisiae has been determined and analysed. The sequence encodes 26 open reading frames of at least 100 amino acids. Eight of these correspond to known genes, whereas 18 correspond to new genes.     

Clostridium difficile-associated diarrhea: epidemiology, risk factors, and infection control

OBJECTIVES: To evaluate the effectiveness of specific infection control measures on the incidence of Clostridium difficile-associated diarrhea (CDAD) and to identify risk factors for its development. SETTING: 370-bed, tertiary-care teaching hospital with approximately 12,000 to 15,000 admissions per year. METHODS: Several infection control measures were implemented in 1991 and 1992, and the attack rates of CDAD were calculated quarterly. Antibiotic use for 1988 through 1993 was analyzed. A case-control study was conducted from January 1992 to December 1992 to identify risk factors for acquisition of CDAD. RESULTS: From 1989 to 1992, the attack rate of CDAD increased from 0.49% to 2.25%. An increase in antibiotic use preceded the rise in the incidence of CDAD in 1991. Despite implementation of various infection control measures, the attack rate decreased to 1.32% in 1993, but did not return to baseline. Ninety-two cases and 78 controls (patients with diarrhea but with negative toxin assay) were studied. By univariate analysis, history of prior respiratory tract infections (odds ratio [OR], 3.6; 95% confidence interval [CI95], 1.2-10.4), the number of antibiotics, and the duration of exposure to second-generation cephalosporins (OR, 3.55; CI95, 1.47-9.41) and to ciprofloxacin (OR, 7.27; CI95, 1.13-166.0) were related significantly to the development of CDAD. By stepwise logistic regression analysis, only exposure to antibiotics and prior respiratory tract infections (P = .0001 and .0203, respectively) were found to be significant. CONCLUSION: Antibiotic pressure might have contributed to failure of infection control measures to reduce the incidence of CDAD to baseline.     

Radon penetration of concrete slab cracks, joints, pipe penetrations, and sealants

Radon movement through 12 test slabs with different cracks, pipe penetrations, cold joints, masonry blocks, sealants, and tensile stresses characterized the importance of these anomalous structural domains. Diffusive and advective radon transport were measured with steady-state air pressure differences controlled throughout the deltaP = 0 to 60 Pa range. Diffusion coefficients (deltaP = 0) initially averaged 6.5 x 10(-8) m2 s(-1) among nine slabs with only 8% standard deviation, but increased due to drying by 0.16% per day over a 2-y period to an average of 2.0 x 10(-7) m2 s(-1). An asphalt coating reduced diffusion sixfold but an acrylic surface sealant had no effect. Diffusion was 42 times higher in solid masonry blocks than in concrete and was not affected by small cracks. Advective transport (deltaP < or = 60 Pa) was negligible for the slabs (10(-16) m2 permeability), pipe penetrations, and caulked gaps, but was significant for cracks, disturbed pipe penetrations, cold joints, masonry blocks, and concrete under tensile stress. Crack areas calculated to be as small as 10(-7) m2 significantly increased radon advection. Algebraic expressions predict air velocity and effective crack width from enhanced radon transport and air pressures. Masonry blocks, open cracks, and slab cold joints enhance radon penetration but stressed slabs, undisturbed pipe penetrations, and sealed cracks may not.     

Pigeon perception and discrimination of rapidly changing texture stimuli

The perception and discrimination of rapidly changing texture stimuli by pigeons was examined in a target localization task. Five experienced pigeons were rewarded for finding and pecking at a randomly placed odd target block of small repeated elements embedded in a larger rectangular array of contrasting distractor elements. On dynamic color test trials, the color of the target, distractor, or both of these regions changed at rates of 100, 250, 500, or 1000 ms per frame. The number of colors appearing within such trials also varied. Pigeons performed well above chance in all test conditions, with target-associated changes producing the best discrimination. The results suggest: (a) global relational information can exclusively guide target localization behavior, (b) pigeons can perceptually group and segregate colored textured differences quite rapidly (< or = 100 ms), and (c) pigeons may possess automatic search control processes that can be captured by stimulus-driven changes in the display.