Cerebral autoregulation in pediatric traumatic brain injury.

OBJECTIVE: The aims of this study were to document the incidence of impaired cerebral autoregulation in children with traumatic brain injury using transcranial Doppler ultrasonography and to examine the relationship between autoregulatory capacity and outcome in children following traumatic brain injury. DESIGN: Prospective cohort study. SETTING: Harborview Medical Center (level I pediatric trauma center) in Washington state. PATIENTS: Thirty-six children <15 yrs old with traumatic brain injury: Glasgow Coma Scale score <9 (n = 12, group 1), Glasgow Coma Scale score 9-12 (n = 12, group 2), and Glasgow Coma Scale score 13-15 (n = 12, group 3). INTERVENTIONS: Cerebral autoregulation testing was conducted during extracranial surgery. Mean middle cerebral artery flow velocities were measured using transcranial Doppler as mean arterial pressure was increased to whichever variable was greater: 20% above baseline or a set value (80 mm Hg for <9 yrs and 90 mm Hg for 9-14 yrs). Autoregulatory capacity was quantified by the Autoregulatory Index. Autoregulatory Index <0.4 was considered impaired cerebral autoregulation. Discharge outcome using the Glasgow Outcome Scale score was considered good if the Glasgow Outcome Scale score was > or =4. MEASUREMENTS AND MAIN RESULTS: Twenty-four (67%) of 36 children had an Autoregulatory Index > or =0.4. The incidence of impaired cerebral autoregulation was 42% (five of 12) in group 1, 42% (five of 12) in group 2, and 17% (two of 12) in group 3. Ten (42%) of the 24 children with intact cerebral autoregulation had a good outcome compared with only one of 12 (8%) children with impaired cerebral autoregulation (p =.04). Six of 12 (50%) children with impaired cerebral autoregulation had hyperemia compared with one of 24 (4%) children with intact cerebral autoregulation (p <.01). Hyperemia was associated with poor outcome (p =.01). CONCLUSIONS: The incidence of impaired cerebral autoregulation was greatest following moderate to severe traumatic brain injury. Impaired cerebral autoregulation was associated with poor outcome. Hyperemia was associated with impaired cerebral autoregulation and poor outcome.     

Neuro-ophthalmic complications of sarcoidosis

Sarcoidosis is a systemic disorder that is caused by granulomatous changes of uncertain etiology and commonly has multiorgan involvement. Ocular involvement may occur in up to 32% of persons afflicted by sarcoid. The neuro-ophthalmic manifestations of sarcoid, in particular, are varied and may affect any portion of the visual system, including neural structures. Diagnosis is often difficult due to the fact that the clinical presentation can mimic other disorders, such as Multiple Sclerosis, and therefore a systematic approach to testing must be used once the diagnosis has been considered. The importance of diagnosing neuro-ophthalmic sarcoid lies in the fact that it is a treatable disease. The mainstay of treatment is corticosteroids although other immunosuppressive agents may be used. The long-term prognosis of neuro-ophthalmic sarcoid has not been studied in large patient populations, but the data that is available suggests that remission may occur in up to 47%.     

Racial differences in the prevalence of dementia among patients admitted to nursing homes

OBJECTIVE: The purpose of this study was to determine the prevalence of dementia among black and white residents on admission to nursing homes and to determine whether demographic and health characteristics known to be associated with dementia were correlated with dementia in this population. METHODS: Data from medical records and structured interviews with family members, nursing staff, and nursing home residents were gathered for 2,285 persons newly admitted to nursing homes in Maryland from 1992 to 1995. A stratified sample of 59 nursing homes was used. An expert panel of five physicians classified each resident as demented, nondemented, or indeterminate. Associations between dementia status, race, and selected characteristics were examined. RESULTS: Black residents (77 percent) were significantly more likely than white residents (57 percent) to be classified as demented. Older age was associated with dementia in both races. Less education, male gender, and a history of a cerebrovascular accident were associated with an increased prevalence of dementia among white residents only. After demographic and health characteristics associated with dementia were controlled for, black race remained independently associated with a diagnosis of dementia. CONCLUSIONS: The rate of dementia on admission to nursing homes was higher among black residents than among white residents, a finding that has implications for the delivery of care. The higher rate may be due to psychosocial factors operating differently in blacks and whites that influence the timing of admission to a nursing home.     

Hepatic metastases from breast carcinoma: comparison of noncontrast, arterial-dominant, and portal-dominant phase spiral CT

PURPOSE: The purpose of this work was to determine the relative value of noncontrast (NC), arterial-dominant (AD), and portal-dominant (PD) phase images in spiral CT of the liver for breast cancer metastases. METHOD: Forty-four spiral CT scans in 18 patients with hepatic metastases from breast cancer were retrospectively reviewed by three radiologists. Subjective evaluations of overall lesion conspicuity and margination were graded on a 5 point scale for NC, AD, and PD phase images, and the three phases were also ranked for demonstration of overall tumor volume. Those scans with hypervascular lesions were separately analyzed, resulting in three groups (all, hypervascular, hypovascular). RESULTS: For lesion conspicuity and margination for the entire study group, AD phase images showed the lowest grades (1.97 and 1.83), whereas the PD phase showed the highest grade (3.34 and 3.14; p < 0.0001) followed by NC (2.36 and 2.42; p < 0.0001). For the hypervascular subgroup, the AD phase also showed the lowest grades (2.39 and 2.24). In no case did the AD phase show more lesions than the combination of NC and PD phases. For depiction of overall tumor volume, the AD phase had the lowest ranking (2.51) compared with the NC and PD phases (1.71 and 1.78; p < 0.001). For the hypervascular subgroup, the AD phase had the lowest ranking (2.33) compared with the NC and PD phases (1.39 and 2.27; p < 0.0001). CONCLUSION: The AD phase is not required for lesion detection in spiral CT for hepatic metastases from breast carcinoma. The NC phase depicts the maximal tumor volume.     

头皮糠疹与巯氧吡啶锌

头皮糠疹是常见病是多发病,临床表现为头皮红斑和脱屑,提示皮损部位表皮结构和功能异常,头皮角质层代谢紊乱,最近对头皮糠疹病因和病理的研究证实马拉色菌,皮脂分泌和个体敏感性是形成上述皮损的3个关键因素,硫氧吡啶锌（PTZ或ZPT）可以有效地杀灭马拉色菌,PTZ的颗粒大小和形状对其在头皮的生物利用度有明显的影响。此外,PTZ的抗菌效果有赖于其分子结构的完整性,在外用制剂中加入附加的游离锌,可以有效防止PTZ解离,从而提高其疗效。     

Effects of histamine-receptor antagonists on histamine-stimulated renin secretion

The effects of histamine H1- and H2-receptor antagonists on histamine-stimulated renin secretion were examined in anesthetized dogs. Tripelennamine (H1 blocker) further enhanced renin secretion in the presence of exogenous histamine. Moreover, tripelennamine alone increased renin secretion. These effects are probably due to non-specific properties of the drug and not to interaction of tripelennamine with H1 receptors. Conversely, cimetidine (H2 blocker) significantly inhibited histamine-induced increases in renin secretion, renal blood flow, and sodium excretion without any changes in mean arterial blood pressure or glomerular filtration rate. Cimetidine alone had no effect. We conclude that H2 receptors mediate the effect of histamine on renin secretion in dogs with innervated, intact kidneys.     

Interactions of gold coordination complexes with DNA

The interactions of certain gold(I) and gold(III) complexes with isolated plasmid pBR322 DNA were defined and compared to those of cis-diamminedichloroplatinum(II), CDDP, using an agarose gel electrophoresis assay. Trichloro(pyridine)gold(III) appeared to bind to DNA as evidenced by its ability to produce dose-dependent changes in the electrophoretic mobilities of closed circular, supercoiled, closed circular, relaxed, and open circular plasmid DNAs. These effects suggest that the gold containing complex induces conformational changes in the plasmid as a result of the compound binding to the DNA and the subsequent unwinding of the double helix and shorting of the DNA. Auranofin [(2,3,4,6-tetra-O-acetyl-1-thio-beta-D-glucopyranosato-S)-triethyl phosphine gold(I)] did not appear to interact with DNA under any conditions. However, its analog chloro(triethylphosphine) gold(I) interacted with DNA at pH 9.5 in borate buffer and produced electrophoretic mobility changes in pBR322 DNA which were different from those produced by the gold(III) complexes that were evaluated. Binding of chloro(triethylphosphine) gold(I) was inhibited by the co-addition of the thiosugar portion of auranofin suggesting preferential binding of the gold moiety to thiosugar, which results in the production of auranofin (or a sugar containing) gold complex and inhibition of gold binding to DNA. The interactions of a number of gold compounds with DNA were also evidenced by their abilities to inhibit the binding of ethidium bromide to DNA. The results from these studies indicate that: gold containing complexes can bind to, and produce conformational changes in, DNA; gold(I) and gold(III) complexes may interact with DNA via different chemical mechanisms to produce different conformational changes in DNA; and certain coordinating ligands in gold complexes (e.g. Cl, Br and SCN) can be exchanged for binding sites on DNA by gold.     

Magnetic resonance imaging diagnosis of disseminated necrotizing leukoencephalopathy

Disseminated necrotizing leukoencephalopathy is a rare syndrome of progressive neurologic deterioration seen most often in patients who have received central nervous system irradiation combined with intrathecal or systemic chemotherapy in the treatment or prophylaxis of various malignancies. Magnetic resonance imaging was more sensitive than computed tomography in detecting white matter abnormalities in the case of disseminated necrotizing leukoencephalopathy reported here. Magnetic resonance imaging may be useful in diagnosing incipient white matter changes in disseminated necrotizing leukoencephalopathy, thus permitting early, appropriate therapeutic modifications.     

Surveillance of Bungowannah Pestivirus in the Upper Midwestern USA

Pestiviruses, a genetically and antigenically highly diverse group, include one of the most historically significant swine pathogens, that is, classical swine fever virus. In Australia, investigations into swine outbreaks characterized by neonatal mortality, stillbirths and mummified foetuses resulted in the discovery of a new pestivirus, Bungowannah virus. This finding raised the possibility that Bungowannah virus, or a variant thereof, was circulating in swine herds elsewhere in the World. If so, it raised the possibility of a pestivirus emerging as a new swine disease with unknown consequences for animal health and food safety. Thus, we developed three specific qRT‐PCR assays to evaluate tissue samples from undiagnosed cases of abortion or respiratory disease for evidence of Bungowannah virus. Examination of 64 samples collected between the Fall of 2007 and Spring of 2010 tested negative for all three genes examined. We conclude that Bungowannah‐like pestivirus is unlikely to be present in swine in the upper Midwestern USA.