Ultra-early evaluation of regional cerebral blood flow in severely head-injured patients using xenon-enhanced computerized tomography.

The role of cerebral ischemia in the pathophysiology of traumatic brain injury is unclear. Cerebral blood flow (CBF) measurements with 133Xe have thus far revealed ischemia in a substantial number of patients only when performed between 4 and 12 hours postinjury. But these studies cannot be performed sooner after injury, they cannot be done in patients with intracranial hematomas still in place, and they cannot detect focal ischemia. Therefore, the authors performed CBF measurements in 35 comatose head-injured patients using stable xenon-enhanced computerized tomography (CT), simultaneously with the initial CT scan (at a mean (+/- standard error of the mean) interval of 3.1 +/- 2.1 hours after injury). Seven patients with diffuse cerebral swelling had significantly lower flows in all brain regions measured as compared to patients without swelling or with focal contusions; in four of the seven, cerebral ischemia (CBF less than or equal to 18 ml/100 gm.min-1) was present. Acute intracranial hematomas were associated with decreased CBF and regional ischemia in the ipsilateral hemisphere, but did not disproportionately impair brain-stem blood flow. Overall, global or regional ischemia was found in 11 patients (31.4%). There was no correlation between the presence of hypoxia or hypertension before resuscitation and the occurrence of ischemia, neither could ischemia be attributed to low pCO2. Ischemia was significantly associated with early mortality (p less than 0.02), whereas normal or high CBF values were not predictive of favorable short-term outcome. These data support the hypothesis that ischemia is an important secondary injury mechanism after traumatic brain injury, and that trauma may share pathophysiological mechanisms with stroke in a large number of cases; this may have important implications for the use of hyperventilation and antihypertensive drugs in the acute management of severely head-injured patients, and may lead to testing of drugs that are effective or have shown promise in the treatment of ischemic stroke.     

The future of outcomes measurement: item banking,tailored short-forms,and computerized adaptive assessment

The use of item banks and computerized adaptive testing (CAT) begins with clear definitions of important outcomes, and references those definitions to specific questions gathered into large and well-studied pools, or “banks” of items. Items can be selected from the bank to form customized short scales, or can be administered in a sequence and length determined by a computer programmed for precision and clinical relevance. Although far from perfect, such item banks can form a common definition and understanding of human symptoms and functional problems such as fatigue, pain, depression, mobility, social function, sensory function, and many other health concepts that we can only measure by asking people directly. The support of the National Institutes of Health (NIH), as witnessed by its cooperative agreement with measurement experts through the NIH Roadmap Initiative known as PROMIS (www.nihpromis.org), is a big step in that direction. Our approach to item banking and CAT is practical; as focused on application as it is on science or theory. From a practical perspective, we frequently must decide whether to re-write and retest an item, add more items to fill gaps (often at the ceiling of the measure), re-test a bank after some modifications, or split up a bank into units that are more unidimensional, yet less clinically relevant or complete. These decisions are not easy, and yet they are rarely unforgiving. We encourage people to build practical tools that are capable of producing multiple short form measures and CAT administrations from common banks, and to further our understanding of these banks with various clinical populations and ages, so that with time the scores that emerge from these many activities begin to have not only a common metric and range, but a shared meaning and understanding across users. In this paper, we provide an overview of item banking and CAT, discuss our approach to item banking and its byproducts, describe testing options, discuss an example of CAT for fatigue, and discuss models for long term sustainability of an entity such as PROMIS. Some barriers to success include limitations in the methods themselves, controversies and disagreements across approaches, and end-user reluctance to move away from the familiar.     

Intestinal bacterial metabolism of flavonoids and its relation to some biological activities

Flavonoid glycosides were metabolized to phenolic acids via aglycones by human intestinal microflora producing α-rhamnosidase, exo-β-glucosidase, endo-β-glucosidase and/or β-glucuronidase. Rutin, hesperidin, naringin and poncirin were transformed to their aglycones by the bacteria producing α-rhamnosidase and β-glucosidase or endo-β-glucosidase, and baicalin, puerarin and daidzin were transformed to their aglycones by the bacteria producing β-glucuronidase, C-glycosidase and β-glycosidase, respectively. Anti-platelet activity and cytotoxicity of the metabolites of flavonoid glycosides by human intestinal bacteria were more effective than those of the parental compounds. 3,4-Dihydroxyphenylacetic acid and 4-hydroxyl-phenylacetic acid were more effective than rutin and quercetin on anti-platelet aggregation activity. 2,4,6-Trihydroxybenzaldehyde, quercetin and ponciretin were more effective than rutin and ponciretin on the cytotoxicity for tumor cell lines. We insist that these flavonoid glycosides should be natural prodrugs.     

Multiple internal resorptions in deciduous teeth: a case report

We report a case of rare multiple internal resorptions. Etiology of multiple internal resorptions is unknown. Interestingly, the patient had an atopic dermatitis, which is possibly related to multiple and rapid internal resorptions.     

Bilateral versus unilateral sudden sensorineural hearing loss.

OBJECTIVES: To analyze the clinical characteristics and treatment results between bilateral (bi-) and unilateral (uni-) sudden sensorineural hearing loss (SSNHL). STUDY DESIGN AND SETTING: A retrospective study. METHODS: Three hundred twenty-four patients with SSNHL were classified into two groups; simultaneous bi-SSNHL (n = 16) and uni-SSNHL (n = 308). We compared clinical characteristics, medical history, hearing level, and treatment results between the 2 groups. RESULTS: The incidence of bi-SSNHL was 4.9 percent of overall patients with SSNHL. Bi-SSNHL occurs more commonly in patients of older age, with preexisting diabetes mellitus, and lipid panel abnormalities compared with uni-SSNHL. Ten patients (62.5%) in the bi-SSNHL group showed hearing recovery in 1 or both ears compared with 56.5 percent of patients with uni-SSNHL. Only 12 (37.5%) of all 32 ears recovered in bi-SSNHL, which was significantly lower than in uni-SSNHL. CONCLUSION: Bi-SSNHL has a very low incidence and lower recovery rate than uni-SSNHL. Recognition of similarities and differences between bilateral and unilateral SSNHL can help in counseling and managing the patients.     

Flavonoids from the leaves ofRhododendron brachycarpum

The flavonoids isolated from the leaves ofRhododendron brachycarpum, were identified as quercetin, avicularin, quercitrin and hyperin.     

A novel cycloartane glycoside fromThalictrum uchiyamai

A new cycloartane glycoside (1) was isolated from the aerial part ofThalictrum uchiyamai Nakai (Ranunculaceae). On the basis of chemical and physicochemical evidence, the aglycone structure of this compound was characterized as 16,25-dihydroxy-3,24-diacetoxy-9, 19-cycloartane-29-oic acid, a new derivative of cycloartane triterpene. Also, the oligosaccharide moiety of this glycoside were determined as 29-O-α-L-rhanmnopyranosyl-(1→2)-[β-D-xylofuranosyl-(1→6)]-β-D-glucopyranosy by application of HMBC technique. Consequently, the structure of compound 1 was elucidated as 29-O-α-L-rhanmnopyranosyl-(1→2)-[β-D-xylofuranosyl-(1→6)]-β-D-glucopyranosyl-16, 25-dihydroxy-3,24-diacetoxy-9,19-cycloartane-29-oic acid ester.