Low-income African-American mothers' perception of exposure to racial discrimination and infant birth weight

We performed a hospital-based case-control study of African-American mothers to explore the relation between a mother's perception of exposure to racial discrimination during pregnancy and very low birth weight. We administered a structured questionnaire to low-income mothers of very low birth weight (<1500 gm; N = 25) and non-low birth weight (>2500 gm; N = 60) infants. The unadjusted and adjusted odds ratio of very low birth weight for maternal exposure to racial discrimination were 1.9 (0.5-6.6) and 3.2 (0.9-11.3), respectively. We conclude that maternal perception of exposure to racial discrimination during pregnancy may be associated with very low birth weight in their infants.     

Peritonitis due to Leuconostoc species in a child receiving peritoneal dialysis

Leuconostoc species are rarely pathogenic in humans, but may cause infection in patients at risk. A 7-year-old girl with p-ANCA-positive crescentic glomerulonephritis, treated with peritoneal dialysis, developed peritonitis due to Leuconostoc species. She had a history of treatment with vancomycin and a brief course of immunosuppressive therapy. The peritonitis responded well to ampicillin therapy. To date, only 47 cases of Leuconostoc infection, including our patient, have been reported in the medical literature; 25 of the cases occurred in children. Only 1 prior case has been reported in the setting of peritoneal dialysis. The risk factors for Leuconostoc infections are not clear, but commonly associated conditions include immunocompromised status and indwelling medical devices. Leuconostoc species are easily misidentified as streptococci in culture, but they possess inherent resistance to vancomycin despite sensitivity to most other antibiotics. In patients with gram-positive peritonitis, Leuconostoc should be considered as a possible etiological agent, particularly if vancomycin resistance is noted in an organism thought to be a Streptococcus species.     

Intravitreal injection of adeno-associated viral vectors results in the transduction of different types of retinal neurons in neonatal and adult rats: a comparison with lentiviral vectors

Replication-deficient viral vectors encoding the marker gene green fluorescent protein (GFP) were injected into the vitreous of newborn, juvenile (P14), and adult rats. We tested two different types of modified virus: adeno-associated viral-2-GFP (AAV-GFP) and lentiviral-GFP vectors (LV-GFP). The extent of retinal cell transduction in different-aged animals was compared 7, 21, and 70 days after eye injections. At all postinjection times, LV-GFP transduction was mostly limited to pigment epithelium and cells in sclera and choroid. In contrast, transduction of large numbers of neural retinal cells was seen 21 and 70 days after AAV-GFP injections. AAV-GFP predominantly transduced neurons, although GFP-positive Müller cells were seen. All neuronal classes were labeled, but the extent of transduction for a given class varied depending on injection age. After P0 injections about 50% of transduced cells were photoreceptors and 30-40% were amacrine or bipolar cells. After adult injections 60-70% of transduced cells were retinal ganglion cells. In adults many GFP-positive retinal axons were traced through the optic nerve/tract and terminal arbors were visualized in central targets.     

Hyperhomocysteinemia evoked by folate depletion: effects on coronary and carotid arterial function

High circulating concentrations of homocysteine (ie, hyperhomocysteinemia [Hhcy]) impair the vascular function of peripheral conduit arteries and arterioles perfusing splanchnic and skeletal muscle regions. The effects of HHcy on coronary resistance vessel function and other indexes of vascular function, ie, arterial permeability and stiffening, are unclear. We tested the hypotheses that HHcy impairs coronary resistance vessel reactivity; increases carotid arterial permeability; and initiates arterial stiffening. Male rats that consumed folate-replete (CON, n=44) or folate-deplete (HHcy, n=48) chow for 4 to 5 weeks had total plasma homocysteine concentrations of 7+/-2 or 58+/-4 micromol/L, respectively. Maximal acetylcholine-evoked relaxation (approximately 40% vs approximately 60%) and tension development from baseline in response to nitric oxide synthase inhibition (approximately 20% vs approximately 40%) were lower (both P<0.05) in coronary resistance vessels (approximately 120 microm, internal diameter) isolated from HHcy versus CON animals, respectively, whereas sodium nitroprusside-evoked relaxation and contractile responses to serotonin and potassium chloride were similar between groups. Permeability to 4400 MW and 65 000 MW fluorescently labeled (TRITC) dextran reference macromolecules (quantitative fluorescence microscopy) was approximately 44% and approximately 24% greater (P<0.05), respectively, in carotid arteries from HHcy versus CON rats. Maximal strain, evaluated by using a vessel elastigraph, was less ( approximately 32% vs 42%, P<0.05) in carotid arterial segments from HHcy versus CON animals, respectively. Finally, estimates of oxidative (copper-zinc+manganese superoxide dismutase activity) and glycoxidative (pentosidine) stress were elevated (P<0.05) in arterial tissue from HHcy versus CON rats. These findings suggest that moderately severe HHcy evoked by folate-depletion impairs endothelium-dependent relaxation of coronary resistance vessels, increases carotid arterial permeability, and initiates arterial stiffening. HHcy may produce these effects by a mechanism associated with increased oxidative and glycoxidative stress.     

A methodology study to validate a structured diagnostic method used to diagnose female sexual dysfunction and its subtypes in postmenopausal women

The currently accepted gold standard for diagnosis of female sexual dysfunction (FSD) is a nonstandardized interview by a clinician whose field of expertise is FSD. However, the limited number of experts in the field has implications for running efficient large-scale clinical trials. Therefore, we developed a structured diagnostic method (SDM) to enable diagnosis of FSD in postmenopausal women by health care professionals who are not FSD experts. Our study objectives were to evaluate both convergent validity and intrarater reliability of the SDM. The results showed that the method had good convergent validity and excellent intrarater reliability. Thus, we conclude that the SDM can reliably diagnose FSD status and FSD subtypes in postmenopausal women.     

Stress fracture of the clavicle in a patient with no obvious risk factors

A 28-year-old woman presented with right shoulder pain and, after a delay, a diagnosis of clavicular stress fracture was made. The patient gave no history of repetitive abnormal loading of the upper limbs which could have assisted the diagnosis. The authors wish to raise awareness of this rare diagnosis such that it can be considered in the differential for shoulder pain of unclear origin.