HLA-Ehigh /HLA-Ghigh /HLA-IIlow Human iPSC-Derived Cardiomyocytes Exhibit Low Immunogenicity for Heart Regeneration

Although human pluripotent stem cells (hPSCs)-derived cardiomyocytes (hPSC-CMs) can remuscularize infarcted hearts and restore post-infarct cardiac function, post-transplant rejection resulting from human leukocyte antigen (HLA) mismatching is an enormous obstacle. It is crucial to identify hypoimmunogenic hPSCs for allogeneic cell therapy. This study is conducted to demonstrate the immune privilege of HLA-Ehigh /HLA-Ghigh /HLA-IIlow human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs). Ischemia-reperfusion surgery is done to create transmural myocardial infarction in rats. At post-infarct 4 days, hPSC-CMs (1.0×107 cells per kg), including human embryonic stem cell-derived cardiomyocytes (hESC-CMs), HLA-Elow/HLA-Glow/HLA-IIhigh hiPSC-CMs, and HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs, are injected into the infarcted myocardium. Under the treatment of very low dose cyclosporine A (CsA), only HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs survive in vivo and improved post-infarct cardiac function with infarct size reduction. HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs activate the SHP-1 signaling pathway of natural killer (NK) cells and cytotoxic T cells to evade attack by NK cells and cytotoxic T cells. Herein, it is demonstrated that using a clinically relevant CsA dose, HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs repair the infarcted myocardium and restore the post-infarct heart function. HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSCs are less immunogenic and may serve as platforms for regeneration medicine.

Does Prior Night’s Sleep Impact Next Day’s Executive Functioning? It Depends on an Individual’s Average Sleep Quality

Executive functioning (EF) is a series of fundamental goal-directed cognitive abilities that enable effective learning. Differences in daily sleep quality may covary with fluctuations in EF among youth. Most studies linking sleep to EF rely on between-person differences and average effects for the sample. This study employed an intensive longitudinal design and examined the within-person relations between self-reported prior night’s sleep quality and next day’s EF. Students from Grades 4 to 12 (M age= 14.60, SD = 2.53) completed three behavioral EF tasks repeatedly across approximately one semester. The final analytic sample included 2898 observations embedded in 73 participants. Although, on average, sleep did not significantly covary with EF, there was heterogeneity in within-person sleep-EF relations. Moreover, individuals’ average sleep quality moderated within-person effects. For individuals with low mean sleep quality, a better-than-usual sleep quality was linked to better EF performance. However, for individuals with high mean sleep quality, better-than-usual sleep quality was linked to worse EF performance. Understanding person-specific relations between sleep and EF can help educators optimize EF and learning on a daily basis and produce positive academic outcomes across longer time periods.

Intraindividual fluctuations in sleep predict subsequent goal setting in adolescents

The purpose of this study was to investigate within- and between-person associations between sleep and subsequent goal setting in adolescents. We conducted an intensive repeated measures longitudinal study to assess intra- and inter-individual associations between sleep and goal setting and potential moderators of such associations. Thirty-nine seventh through 12th graders reported on their sleep quality and propensity to set goals in their daily lives several times per week for approximately four months. We used a combination of multilevel modeling with time-varying covariates and centering techniques to partition within- and between-person variance. We found significant and positive associations between sleep and goal setting within individuals, but no such associations between individuals. That is, students were more likely to set goals for their work after getting a good night’s sleep relative to their own average sleep quality, but getting good sleep on average relative to other individuals showed no association with average goal setting. These relationships were not moderated by participant age, gender, or sociodemographic status as indexed by maternal education. Differences in average sleep between adolescents matters less for their propensity to set goals than whether they experienced better- or worse-than-usual sleep the previous night given their own average. This finding represents the first evidence documenting effects of sleep on goal setting, which is an important psychological precursor to many youth behavioral and achievement outcomes. Our findings highlight the individuality of sleep needs and point to new directions for sleep-related practice and policy aimed at youth.

Stressful Experiences, Connection, and Depressive Symptoms Among Taiwanese Han and Indigenous Youth

This study examined Taiwanese Han and indigenous (Tayal) youth’s experiences of stressful life events, the association between stressful experiences and depressive symptomology, and also the indirect and interactive effects of connection on the relationship between stressful experiences and depressive symptomology. Taiwanese Han (97%) is the majority group, whereas indigenous people make up 2.3% of Taiwan’s population. Taiwanese indigenous people have experienced disparities across socio-historical, educational, and economic aspects of their lives. This study included 291 eighth-grade participants (40% from the Tayal tribe, 48.8% female, and M_age = 13.44). The Han sample in this study all lived in cities, and the Tayal sample all lived in the tribal areas of the Northern Taiwan mountain regions. Person-centered (latent class analyses) and cumulative (sum of items) approaches were used to investigate family and school stressful events, respectively. Hierarchical regression analyses were conducted separately for the Han and Tayal participants to examine the role of family and school connection in relation to family and school stressors and depressive symptomology. Our results showed that stressful experiences are clearly linked to depressive symptomology and family connection was important to both Tayal and Han youth in supporting their coping with depressive symptoms. However, Tayal youth might be particularly vulnerable to family stressful events because family stressors disrupted their connection with their parents and thereby minimized the protective function of family relationships. To decrease the likely onset of depression during early adolescence, our results suggest that it is important for parents and other family members to monitor adolescents’ daily experiences of stress and provide support when needed. Furthermore, mental health interventions need to be tailored specifically for youth in specific racial, social, and economic contexts. Tayal youth mental health might benefit particularly from increasing school connection and decreasing stresses experienced in family contexts. Implications, limitations, and recommendations for future research are discussed.

Exploring Idiographic Approaches to Children's Executive Function Performance: An Intensive Longitudinal Study

Traditional variable-centered research on executive functions (EFs) often infers intraindividual development using group-based averages. Such a method masks meaningful individuality and involves the fallacy of equating group-level data with person-specific changes. We used an intensive longitudinal design to study idiographic executive function fluctuation among ten boys from Grade 4. Each of the participants completed between 33 and 43 measurement occasions (M = 38.8) across approximately three months. Data were collected remotely using a computerized short version of the Dimensional Change Card Sort task. Multi-group analyses of three participant pairs (Participants 5 and 3, 5 and 2, and 5 and 6) demonstrated that Participant 5 differed from Participants 3 and 2 in different ways but Participants 5 and 6 were similar in all comparisons. Dynamic structural equation modeling demonstrated unique individual trajectories, which were not represented by the trajectory of group-averages. Although more than half of the participants showed a negative association between EFs and inattention, two participants showed a positive association between EF and inattention. This study demonstrated meaningful person-specific trajectories of EFs, suggesting that future study should undertake the analysis of individual development before data-aggregation or generalization from aggregate statistics to individuals.

Efficient Cardiac Differentiation of Human Amniotic Fluid-Derived Stem Cells into Induced Pluripotent Stem Cells and Their Potential Immune Privilege

Mature mammalian hearts possess very limited regenerative potential. The irreversible cardiomyocyte loss after heart injury can lead to heart failure and death. Pluripotent stem cells (PSCs) can differentiate into cardiomyocytes for cardiac repair, but there are obstacles to their clinical application. Among these obstacles is their potential for post-transplant rejection. Although human amniotic fluid-derived stem cells (hAFSCs) are immune privileged, they cannot induce cardiac differentiation. Thus, we generated hAFSC-derived induced PSCs (hAFSC-iPSCs) and used a Wnt-modulating differentiation protocol for the cardiac differentiation of hAFSC-iPSCs. In vitro studies using flow cytometry, immunofluorescence staining, and patch-clamp electrophysiological study, were performed to identify the characteristics of hAFSC-iPSC-derived cardiomyocytes (hAFSC-iPSC-CMs). We injected hAFSC-iPSC-CMs intramuscularly into rat infarcted hearts to evaluate the therapeutic potential of hAFSC-iPSC-CM transplantation. At day 21 of differentiation, the hAFSC-iPSC-CMs expressed cardiac-specific marker (cardiac troponin T), presented cardiomyocyte-specific electrophysiological properties, and contracted spontaneously. Importantly, these hAFSC-iPSC-CMs demonstrated low major histocompatibility complex (MHC) class I antigen expression and the absence of MHC class II antigens, indicating their low immunogenicity. The intramyocardial transplantation of hAFSC-iPSC-CMs restored cardiac function, partially remuscularized the injured region, and reduced fibrosis in the rat infarcted hearts. Therefore, hAFSC-iPSCs are potential candidates for the repair of infarcted myocardium.

Hybrid proximal linearized algorithm for the split DC program in infinite-dimensional real Hilbert spaces

To be the best of our knowledge, the convergence theorem for the DC program and split DC program are proposed in finite-dimensional real Hilbert spaces or Euclidean spaces. In this paper, to study the split DC program, we give a hybrid proximal linearized algorithm and propose related convergence theorems in the settings of finite- and infinite-dimensional real Hilbert spaces, respectively.

Clathrin-mediated endocytosis is required for ANE 30-100K-induced autophagy

BACKGROUND

We identified an autophagy-inducing areca nut (AN) ingredient (AIAI) in the 30-100 kDa fraction of AN extract (ANE 30-100K). This study was to analyze the role of endocytosis in ANE 30-100K-induced autophagy.

METHODS

We used benzyl alcohol, dynasore, and shRNA of clathrin and dynamin to assess whether ANE 30-100K-induced cytotoxicity and accumulation of microtubule-associated protein 1 light chain 3 (LC3)-II were affected in oral (OECM-1) and esophageal (CE81T/VGH) carcinoma cells.

RESULTS

Both benzyl alcohol and dynasore effectively reduced ANE 30-100K-induced cytotoxicity and LC3-II accumulation in OECM-1 and CE81T/VGH cells. Downregulated protein expression of both clathrin and dynamin by their shRNA also significantly attenuated ANE 30-100K-induced elevation of LC3-II levels in CE81T/VGH cells.

CONCLUSIONS

These results indicate that AIAI may be engulfed by cells through clathrin-mediated endocytosis, which promotes the execution of the following autophagy program.

Surgical resolution of accidental intramuscular injection of Gudair® vaccine in a mare

This case report describes the accidental intramuscular administration of 20 mL Gudair® vaccine to a 7-year-old Standardbred mare and successful treatment of the resulting inflammatory reaction by radical surgical resection.

Do human figure diagrams help alleged victims of sexual abuse provide elaborate and clear accounts of physical contact with alleged perpetrators?

The present study examined whether the use of human figure diagrams within a well-structured interview was associated with more elaborate and clearer accounts about physical contact that had occurred in the course of an alleged abuse. The sample included investigative interviews of 88 children ranging from 4 to 13 years of age. Children were interviewed using the NICHD Investigative Interview Protocol, and were then asked a series of questions in association with unclothed gender-neutral outline diagrams of a human body. A new coding scheme was developed to examine the types and clarity of touch-related information. Use of the HFDs was associated with reports of new touches not mentioned before and elaborations regarding the body parts reportedly touched. The HFDs especially helped clarify reports by the oldest rather than the youngest children. The clarity of children's accounts of touch was also greater when details were sought using recall prompts.

Acute lobar nephronia in a renal allograft: a case report and literature review

We report a diabetic renal transplant recipient who presented with fever and right lower quadrant abdominal pain. Acute appendicitis was considered initially and she underwent emergent appendectomy. However, persistent symptoms postoperatively made us perform an imaging study to identify the problems. Abdominal and pelvic computed tomography disclosed several focal wedge-shaped lesions of low attenuation in the renal allograft. Acute lobar nephronia was successfully managed with parenteral antibiotics. The patient recovered without any sequela. A renal allograft in the right iliac fossa complicates the diagnosis among acute renal infection, malignancy, acute rejection, and even acute appendicitis. Biopsy of the renal allograft is sometimes needed due to clinically ambiguous imaging results. In this report, we not only detail the clinical course of such a rare case, but also review the previous 3 cases of acute lobar nephronia in renal allografts in the literature.

Repair of oroantral communications in the third molar region by random palatal flap

Various palatal flap procedures based on the greater palatine vessels have been advocated for the repair of oroantral communications (OACs). However, when the defect is located in the third molar region, difficulty is encountered in using the palatal flap because rotation is hindered by the vascular pedicle. In this study, we used random palatal flaps to repair OACs in the third molar area in 21 patients. The vascular pedicles were ligated and severed in all cases in order to evaluate whether it was necessary to preserve the greater palatine vessels when using the palatal rotation flap (PRF). The repair was successful in 16 cases (76.2%). The length/width ratio of the flap was the most important factor determining the outcome. The ratios were 2.23 +/- 0.12 and 2.40 +/- 0.14 in the success and failure groups, respectively and their difference was statistically significant (P<0.05). Other clinical parameters such as age, gender, antral infection, tooth displacement into the sinus and duration of the communication had no influence on the outcome (P>0.05). The study showed that the PRF with the appropriate length/width ratio can safely be used in a random fashion. This provided another option in the repair of oroantral communications of difficult locations such as in the tuberosity area.

Evaluation of peribulbar anesthesia in encircling scleral buckle surgery and its postoperative pain course

BACKGROUND

Retrobulbar anesthesia is considered effective in ocular surgery but it can give rise to serious complications. We used peribulbar anesthesia with sub-Tenon's irrigation to perform encircling scleral buckling for retinal detachment, as it could reduce the complications caused by retrobulbar anesthesia. We also recorded the course of pain for 72 hours after surgery.

METHODS

Thirty patients who were diagnosed with rhegmatogenous retinal detachment were treated with an encircling scleral buckle. The surgery was performed with peribulbar anesthesia with occasional sub-Tenon's irrigation. We evaluated the patient's pain with a visual analogue scale after surgery at 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24 hours, 48 hours, and 72 hours.

RESULTS

In 24 cases (80%), the anesthesia was complete with the peribulbar block. Only 6 patients (20%) needed sub-Tenon's irrigation and four of them felt no pain after augmentation. Although all the surgical procedures proceeded without problem, two of the patients felt pain and were uncomfortable during the surgery. No serious complications occurred. The course of pain peaked 6 hours after surgery when 26 patients (86.7%) felt pain and 12 patients (40%) were uncomfortable (pain score > or = 5). Forty-eight hours after surgery, 9 patients (30%) still felt pain but no one felt uncomfortable.

CONCLUSION

Peribulbar anesthesia can be used safely in encircling scleral buckling for retinal detachment. The postoperative pain is maximal 6 hours after surgery and becomes mild (pain score < or = 4) after 48 hours.

Arecoline cytotoxicity on human oral mucosal fibroblasts related to cellular thiol and esterase activities

Betel quid (BQ) chewing is associated with an increased risk of oral submucous fibrosis (OSF) and oral cancer in India and many south-east Asian countries. Recently, we have shown that arecoline is cytotoxic to cultured human oral mucosal fibroblasts. This study investigated protective effects of various agents against the cytotoxicity of arecoline and its mechanisms. Arecoline, at concentrations of 0.2 and 0.4 mM, decreased the cell numbers by 38% and 63%, respectively. At a concentration of 2 mM, N-acetyl-L-cysteine [a glutathione (GSH) synthesis precursor] could prevent arecoline-induced cytotoxicity. The decrease in cell numbers was reduced to 17% relative to control. Extracellular addition of esterase at a concentration of 0.1 U/ml could almost completely protect the oral mucosal fibroblast (OMF) from arecoline-induced cytotoxicity. Arecoline is a muscarinic receptor agonist. However, atropine, a muscarinic receptor antagonist was unable to protect the cells from arecoline cytotoxicity at a concentration of 10 microM. Pretreatment of OMF with 50 microM buthionine sulfoximine (a cellular GSH synthesis inhibitor) or 0.5 mM diethylmaleate (a cellular GSH depleting agent) potentiated the cytotoxic effects of arecoline. These results indicate that cytotoxicity of arecoline on OMF is associated with cellular GSH levels and esterase activities. Factors that induce the GSH synthesis or esterase activity of oral mucosal cells can be used for future chemoprevention of BQ chewing-related lesions.

Once-a-month treatment with a combination of mifepristone and the prostaglandin analogue misoprostol

In this two centre study, the efficacy of 200 mg mifepristone orally followed 48 h later by 0.4 mg misoprostol orally for menstrual regulation was investigated. The dose of mifepristone was taken the day before the expected day of menstruation. Each volunteer was planned to participate for up to 6 months. A plasma beta human chorionic gonadotrophin (HCG) was measured on the day of mifepristone intake. The study was disrupted prematurely due to low efficacy. In 125 treatment cycles the overall pregnancy rate was 17.6% (22 pregnancies) and the rate of continuing pregnancies (failure) was 4.0%. Eight women discontinued the study due to bleeding irregularities which were seen in 15 cycles (12%). These effects on bleeding pattern made the timing of treatment day difficult. Late luteal phase treatment with a combination of mifepristone and misoprostol is not adequately effective for menstrual regulation.

Cytotoxic and cytostatic effects of arecoline on oral mucosal fibroblasts

Betel quid (BQ) chewing shows strong correlation to the incidence of oral submucous fibrosis and oral cancer in Taiwan. Arecoline, the main areca alkaloid, is considered to be one of the etiologic factors in BQ. To elucidate the role(s) of arecoline in the pathogenesis of BQ chewing related oral mucosal lesions, we used oral mucosal fibroblasts to study the effects of serum concentration, cell density, and incubation time on the cytotoxic response to arecoline. At a concentration less than 0.2 mM, arecoline was not cytotoxic to oral mucosal cells after 1, 3, and 6 days of incubation. After 3 days of incubation, the cytotoxic and cytostatic effects of arecoline became evident when the cells were exposed to higher concentrations of arecoline (0.2 mM) and serum (10% FCS). Exposure of cells (1 x 10(4) cells/well) to 0.2 mM of arecoline in 0.5% FCS for 3 and 6 days led to a 20% and 23% decrease, respectively, in the cell number, whereas exposure of cells (1 x 10(4) cells/well) to 0.2 mM arecoline in 10% FCS led to a 38% and 53% decrease, respectively, in cell number. At a higher cell density (5 x 10(4) and 1 x 10(5) cells/well), 0.2 mM arecoline led to less cytotoxicity (38% and 21% of decreasing in cell number, respectively) after 6 days of incubation. Our results indicated that arecoline was not mitogenic to oral mucosal fibroblasts, and that the cytotoxic and cytostatic effects of arecoline on oral mucosal fibroblasts could be modulated by the changes in the cell density, serum concentrations, and incubation time.

[A study on the relation between cerebral lesion and cognitive defect in multi-infarct patients]

240 cases of multi-infarct patients with more than two cerebral infarct lesions in CT findings were collected successively from 1991 to 1992. 42.92% of them were shown to have cognitive defect with a series of neuropsychological tests. Correlation of the occurrence of cognitive defect with the CT findings such as the location and extent of focal lesions as well as the presence of cerebral atrophy or subcortical degeneration were carried out. According to the results by multiple regression and factor analysis, the location and extent of the focal infarct lesions were not the primary determining factor for the occurrence of cognitive defect. It is, therefore, suggested that the term of ischemic or vascular dementia be used clinically instead of the so-called multi-infarct dementia.

Effects of different doses of norethisterone on ovarian function, serum sex hormone binding globulin and high density lipoprotein-cholesterol

The ovarian effects of different doses of norethisterone (NET) were compared in 45 normally menstruating women in order to find the lowest effective dose of the Chinese NET "visiting pill". Subjects were randomly divided into 3 groups. Each subject in each group was taking 0.5, 1.5 or 3.0 mg per day from days 5 to day 18 of the cycle. Blood samples were taken on days 5, 8, 11, 14, 17, 20, 23, 26 and 29 of the cycle. Serum oestradiol (E2), progesterone (P), sex hormone binding globulin (SHBG), high density-lipoprotein cholesterol (HDL-C), and NET concentrations were measured. Ovulation, delayed ovulation, ovulation inhibition and follicular activity were classified by the analysis of the peripheral serum levels of sex hormones. Ovulation occurred in 7 women in the 0.5 mg group, in 2 women in the 1.5 mg group and in none of the 3.0 mg group. Mean serum SHBG levels were reduced progressively by 6.6% (Group 0.5), 15.5% (Group 1.5) and 23.4% (Group 3.0). There were no significant changes in HDL-C levels in any group. There was a significant correlation of mean serum NET concentrations with dose. The lack of complete inhibition of ovulation in most women in the 1.5 mg and 0.5 mg groups might suggest that the dose of NET required when used as a visiting pill could not be reduced below 3.0 mg.

A cross-over study of three oral contraceptives containing ethinyloestradiol and either desogestrel or levonorgestrel

A randomised cross-over trial was performed to compare the pharmacodynamic actions of three low-dose oral contraceptives (OCs): Marvelon (150 micrograms desogestrel (DSG)+ 30 micrograms ethinyloestradiol (EE)), Mercilon (150 micrograms DSG + 20 micrograms EE) and Microgynon (150 micrograms levonorgestrel (LNG) + 30 micrograms EE). None of the OCs produced any significant changes in serum cholesterol, LDL-C and apoprotein B. Triglycerides were increased by the desogestrel OCs but not by Microgynon. The latter however increased the glucose and insulin responses to a glucose tolerance test whereas Marvelon and Mercilon had no effect. HDL-C increased with Marvelon, was unchanged with Mercilon and was decreased with Microgynon. Apoprotein AII was increased by all three OCs but only the DSG OCs increased apoprotein AI. All OCs produced similar increases in caeruloplasmin but the increase in SHBG was much greater with Marvelon and Mercilon than with Microgynon. Testosterone was reduced more with Microgynon than with the DSG OCs. Many of the changes reflect the strong anti-oestrogenic action of LNG on metabolic parameters compared to DSG. Except for the effect on HDL-C, there was little difference between Marvelon and Mercilon on metabolic parameters and this complements the findings from large-scale clinical trials of the two OCs. Mercilon, therefore provides a very satisfactory alternative to Marvelon.

Ni-Ti memory alloy clamp plate for fracture of short tubular bone

The clamp shape implant has a special memorial function. It consists of one main rod and 3 or 4 pairs of curved short arms located at both sides of the rod. Each pair of arms rolls into a circle, which can embrace 2/3 of the circumference of the fractured bone shaft, thus fixing fragmental bones at multiple points more securely without any limitation to the motion of adjacent joints. Therefore, clamp implant is especially useful for comminuted fracture of the short tubular bone, which is difficult to fix by other methods.

A pharmacodynamic and pharmacokinetic study of the Chinese No. 1 pill

A pharmacodynamic and pharmacokinetic study of the Chinese No. 1 pill, a combined oral contraceptive containing 35 micrograms ethynyloestradiol (EE) and 600 micrograms norethisterone (NET), was performed in 29 women over a period of six months. Blood samples for analysis were taken during a pretreatment cycle, the first and 6th treatment cycles and post-treatment. Minor changes in carbohydrate metabolism occurred and these were particularly noticeable when the incremental areas under the serum concentration-time curves for both glucose and insulin in response to a glucose tolerance test were calculated. No changes occurred in the serum glycosylated haemoglobin levels. The serum concentrations of all the lipids measured (total cholesterol, triglycerides, LDL-C, HDL-C and apolipoproteins AI, AII and B) were significantly increased on treatment as were levels of Factor X, SHBG and caeruloplasmin whereas antithrombin III decreased. In 38 of the 40 treatment cycles, ovulation was suppressed. In one cycle serum oestradiol and progesterone levels showed a typical ovulatory pattern and in another there was evidence of follicular activity without ovulation. Serum EE concentrations showed a similar pattern in both treatment cycles showing that co-administration of NET did not affect EE metabolism. Serum NET levels were higher in the 6th than in the first treatment cycles. On comparing pharmacodynamic and pharmacokinetic parameters, the only statistically significant correlations were between the percentage change in triglycerides and SHBG and serum NET, but not EE concentrations, and between apolipoproteins AI and serum EE.

Spinal cord compression due to metastatic disease: diagnosis with MR imaging versus myelography

To determine the efficacy of magnetic resonance (MR) imaging and myelography for the diagnosis of spinal cord compression due to metastatic disease, the authors prospectively examined 70 patients who had known or suspected spinal involvement by malignancy. Most MR examinations consisted of T1-weighted sagittal imaging of the entire spine, with additional sequences as needed for clarification. Extradural masses were found in 46 patients, 25 of whom had cord compression. For extradural masses causing cord compression, the sensitivity and specificity of MR imaging was .92 and .90, respectively, compared with .95 and .88 for myelography. For extradural masses without cord compression the sensitivity and specificity of MR imaging was .73 and .90, versus .49 and .88 for myelography. MR imaging was much more sensitive for metastases to bone (.90 vs .49), as expected. MR imaging is an acceptable alternative to myelography for diagnosing spinal cord compression and is preferable as a first study because it is noninvasive and better tolerated.

The use of nickel-titanium alloy in orthopedic surgery in China

A new biomaterial made of nickel and titanium with its shape-memory characteristics has been manufactured, investigated, and used in Shanghai, China. Since 1981, this biomaterial has been used in 265 cases clinically, among which 71 involved orthopedic surgery. Results are satisfactory without failure in our short-term follow up. This preliminary report of the use of this new biomaterial with the unique characteristic of being able to recover to its original shape with particular transformation temperatures indicates its potential for opening a new field for investigation in surgery. Research to discover appropriate ratios of nickel and titanium for specific usage is underway. The interest and cooperation between the medical and engineering professions may eventually solve the problems through mutual efforts and result in improved shape-memory biomaterials.

Transvenous embolization of direct carotid cavernous fistulas

Of 165 cases of direct carotid cavernous fistula, 14 (8.5%) were treated from a transvenous approach. Twelve of these were treated through the inferior petrosal sinus and one through the superior ophthalmic vein. In one patient, both approaches were used. The embolic agents were as follows: five patients had balloons only, four patients had minicoils alone, three patients had coils and liquid adhesives, one had balloons and coils, and one had balloons and liquid adhesives. Among the patients who were treated from a transvenous approach, three had an occluded carotid artery caused by trauma, nine failed transarterial balloon attempts, and one had a prior trapping procedure. In the remaining patient, who had Ehlers-Danlos syndrome, a transarterial approach was judged to be too dangerous. This patient suffered a fatal pontine hemorrhage after subtotal transvenous occlusion of the carotid cavernous fistula with diversion of flow into cortical veins. Another complication occurred when the inferior petrosal sinus was perforated during catheterization, causing a small subarachnoid hemorrhage. The tear was immediately closed with minicoils, and surgical exposure and embolization resulted in complete cure. Of the remaining 12 patients treated, 11 were completely cured and one showed angiographic and clinical improvement. Transarterial balloon embolization remains the procedure of choice in the treatment of symptomatic carotid cavernous fistulas; however, transvenous embolization is an alternative when the arterial route fails.

Conventional vs computed radiography: evaluation of myelography

A prospective study was performed to compare the diagnostic efficacy of conventional film-screen (FS) imaging with computed radiography (CR) in myelography. Forty examinations were done with both methods. Digital myelography was found to have diagnostic accuracy equal to that of conventional film-screen examinations.

Platinum wire: a new transvascular embolic agent

Standard Gianturco and "mini" coils cannot be used with some of the present microcatheter systems. However, occasions arise in which metallic coils would be an ideal embolic agent in vascular structure accessible only to a tracker (2.2-French) catheter system. We performed nine embolization procedures in eight patients with arteriovenous fistulas using platinum coils as an embolic agent. Fistulas were completely occluded in six of the nine cases. In several cases, platinum wire embolization was augmented with other agents. Complications occurred in two cases, neither resulting in permanent neurologic deficits. Advantages of using platinum coils included availability, radioopacity, thrombogenicity, biocompatibility, and delivery through microcatheters, specifically the tracker catheter system.

Intracranial non-Hodgkin lymphoma occurring after treatment of Hodgkin disease

Patients with successfully treated Hodgkin disease are at increased risk for the development of second malignancies. We present two cases of intracranial non-Hodgkin lymphoma that appeared following successful treatment of Hodgkin disease. The appearance of the lymphomas on computed tomographic images is shown, and possible predisposing factors, differential diagnosis, and clinical implications are discussed.

Computed tomography in hematologic malignancies of paranasal sinuses

Hematologic malignancies of the paranasal sinuses are uncommon. Four young patients with ophthalmologic abnormalities as a chief complaint are presented. Lymphoma or leukemia should be considered in the differential diagnosis of destructive lesions in the paranasal sinuses, particularly in children and young adults.

Cranial metastases from prostate cancer simulating meningioma: report of two cases and review of the literature

Two cases of prostatic carcinoma metastatic to the cranium that presented with clinical and radiographic features simulating meningioma are described. The literature was reviewed, and 13 similar cases were identified. From the data gathered, we conclude that metastatic prostate cancer should be considered in the differential diagnosis of elderly males who present with characteristic clinical and radiological features of meningioma and that the classical description of meningioma is not specific.

A pharmacokinetic and pharmacodynamic study of a 'visiting pill' containing norethisterone

The pharmacokinetics and pharmacodynamic effects of two doses of norethisterone (5mg and 3mg) used as a 'visiting pill' were investigated. There were no significant differences in the pharmacokinetics of the two doses except for the peak concentration achieved and the bioavailability as assessed by the area under the serum norethisterone concentration - time curve. Both doses were rapidly absorbed. Pharmacodynamic effects were minor. No change occurred in serum concentrations of total cholesterol, total triglycerides or HDL-cholesterol. The area under the serum glucose concentration--time curve and particularly the area under the serum insulin concentration--time curve were significantly increased as a result of treatment but no change occurred in the serum levels of glycosylated haemoglobin. SHBG concentrations in serum decreased on treatment whereas those of ceruloplasmin increased.

Vertical fracture of the odontoid: CT diagnosis

A patient with a vertically oriented fracture of the odontoid is described. We found no previous report of this type of fracture. In our patient CT was the best imaging modality for defining the anatomic extent of the fracture.

Dural infolding during C1-2 myelography

Inward buckling of the dura at C1-2 may occasionally occur with hyperextension of the neck and can result in a difficult or unsuccessful puncture when the posterior lateral C1-2 approach is used for cervical myelography. In this circumstance, placement of the head in a neutral or slightly flexed position may widen the posterior subarachnoid space and facilitate the needle puncture.