Synthesis, structure, and reactivity of closo-2,3,4,5,6,7,8,9,10,11-decahydroxy-1,12-bis(sulfonic acid)-1,12-dicarbadodecaborane(12)

The reaction of closo-1,12-bis(lithio)-1,12-dicarbadodecaborane(12) (1,12-bis(lithio)-p-carborane) with SO(2) formed closo-1,12-bis(lithiosulfinato)-p-carborane (10) in nearly quantitative yield. The latter was converted to closo-1,12-bis(sulfinic acid)-p-carborane (13) via H(+)-exchange. The corresponding 1,12-bis(sulfonic acid) derivative of p-carborane (12) was obtained in high yield by treating 10 with SO(2)Cl(2) and subsequent AlCl(3) mediated hydrolysis of the closo-1,12-bis(chlorosulfonyl)-p-carborane intermediate. The exhaustive oxidation of 12 in hot aqueous H(2)O(2) (30%) afforded B-decahydroxy-1,12-bis(sulfonic acid)-p-carborane (15) in 40% yield. As a byproduct, closo-B-decahydroxy-1-sulfonic acid-p-carborane (14) was formed. Both 14 and 15 were also obtained from the hydroxylation of 10 and 13. Compound 14 was obtained directly in 88% yield by heating 1-sulfinic acid-p-carborane (17) in H(2)O(2) (30%). Compound 17 was synthesized from diphenylmethylsilyl-protected p-carborane by using the method employed in the synthesis of 13. The X-ray structures of 15, its disodium salt, and its dipotassium salt are presented and discussed. Exhaustive methylation of 15 with methyl triflate furnishes closo-B-decamethoxy-1,12-bis(methyl sulfonate)-p-carborane (20). The characterization of closomer 20 also includes its crystal structure determination.

A new method for surgical repair of impression fractures of the cranial vault and frontal sinus with rivet-like titanium clamps

Conventional methods of stabilizing fragments in cranial impression fracture include the use of threads, wires, plates, etc. A new approach to facilitate this surgery is the use of titanium clamps, presented here in five cases, including one with frontal sinus fracture. Surgery was performed on admission day, with the exception of the sinus fracture. Compared with the use of mini- and microplates, the procedure was simple and short. The fixation was very rigid and the esthetic result excellent in all five cases. Skin irritation was minimal, compared with that from miniplates. Computed tomography and MRI compatibility due to artifacts are identical to those with miniplates.

Children's spatial behavior is differentially affected after traumatic brain injury

Spatial behavior in 20 children with severe traumatic brain injury (TBI) and 20 healthy controls was investigated using the Kiel Locomotor Maze. Children had to remember defined locations in an experimental chamber with completely controlled intra- and extra-maze cues until learning criterion was reached. In a second experiment, spatial orientation strategies were assessed. Children with TBI were shown to be impaired in spatial learning and spatial memory. Spatial orientation was found to be deficient even in cases where spatial learning and memory proved to be unimpaired, especially in tasks that demanded the use of relational place strategies. Children who suffered a TBI at an early age proved to be more severely impaired in spatial learning and orientation than older children.

Transient paralysis of the bladder due to wound botulism

In the last 10 years, wound botulism has increasingly been reported and nearly all of these new cases have occurred in injecting-drug abusers. After absorption into the bloodstream, botulinum toxin binds irreversibly to the presynaptic nerve endings, where it inhibits the release of acetylcholine. Diplopia, blurred vision, dysarthria, dysphagia, respiratory failure and paresis of the limbs are common symptoms of this intoxication. Surprisingly and despite the well-known blocking action of the botulinum toxin on the autonomic nerve system, little attention has been paid to changes in the lower urinary tract following acute botulinum toxin poisoning. Here we report a case of bladder paralysis following wound botulism. Early diagnosis and adequate management of bladder paralysis following botulism is mandatory to avoid urologic complications. Accordingly, the prognosis is usually favorable and the bladder recovery complete.

Health issues for women with epilepsy: a descriptive survey to assess knowledge and awareness among healthcare providers

The American Academy of Neurology and the American College of Obstetricians and Gynecologists recently issued practice parameters for women with epilepsy. These parameters suggest optimal care practices. To assess knowledge of the issues covered in the parameters and to facilitate educational efforts to promote best care, the Epilepsy Foundation conducted a survey of healthcare professionals likely to provide care to women with epilepsy. The survey sampled 3535 healthcare professionals across a wide range of specialties. Most respondents did not know the specific effects of estrogen and progesterone on the seizure threshold, were not aware of menstrual-associated seizure patterns, and could not identify which antiepileptic drugs interfere with oral contraceptives. The majority of respondents did not know that women with epilepsy have higher rates of infertility, reproductive endocrine disorders, and sexual dysfunction. Most respondents did not know the frequency of birth defects in children born to women with epilepsy. Providers seeing the largest number of persons with epilepsy were more likely to have correct answers. By specialty, neurologists provided the highest number of correct responses, followed (in descending order) by endocrinologists, obstetricians/gynecologists, internal medicine physicians, family practice physicians, and pediatricians. These results suggest that women with epilepsy are not receiving adequate counseling and that care practices may not conform to those recommended.

Spatial information transfer from virtual to real versions of the Kiel locomotor maze

The Kiel locomotor maze requires participants to choose five targets from among 20 locations marked by small red lights on the floor of a dimly lit circular environment having four wall-mounted extramaze cues and two intramaze cues at floor level. In the present study, acquisition of the real task was examined in 11-year-old children following prior accurate training in a virtual version, following misleading virtual training, or following no training. The virtual version was displayed on a desk-top computer monitor. Acquisition testing in the real maze was either locomotor or non-locomotor. Good transfer was achieved from virtual to real versions. Children's exploration of the real maze prior to real maze acquisition training revealed a clear transfer of spatial information previously learned in the virtual version. Children taught the correct target configuration in the simulation made fewer errors and more rapid, confident responses to targets in the real maze than children given no training. However, acquisition was also better following misleading training than no training, suggesting that a non-specific components of performance also transferred. Male superiority was only seen following misleading training, which was interpreted in terms of male superiority in mental rotation. After acquisition, a single probe trial was performed, in which proximal cues and participants' starting position were rotated, but this had equivalent effects on all groups' performance. It is clear that transfer of spatial information occurs from the simulated Kiel maze to the real version. This has implications for its use in diagnosis and training.

Conserved Ca2+-antagonist-binding properties and putative folding structure of a recombinant high-affinity dihydropyridine-binding domain

Sensitivity to 1,4-dihydropyridines (DHPs) can be transferred from L-type (alpha1C) to non-L-type (alpha1A) Ca(2+) channel alpha1 subunits by the mutation of nine pore-associated non-conserved amino acid residues, yielding mutant alpha1A(DHP). To determine whether the hallmarks of reversible DHP binding to L-type Ca(2+) channels (nanomolar dissociation constants, stereoselectivity and modulation by other chemical classes of Ca(2+) antagonist drugs) were maintained in alpha1A(DHP), we analysed the pharmacological properties of (+)-[(3)H]isradipine-labelled alpha1A(DHP) Ca(2+) channels after heterologous expression. Binding of (+)-isradipine (K(i) 7.4 nM) and the non-benzoxadiazole DHPs nifedipine (K(i) 86 nM), (+/-)-nitrendipine (K(i) 33 nM) and (+/-)-nimodipine (K(i) 67 nM) to alpha1A(DHP) occurred at low nanomolar K(i) values. DHP binding was highly stereoselective [25-fold higher affinity for (+)-isradipine]. As with native channels it was stimulated by (+)-cis-diltiazem, (+)-tetrandrine and mibefradil. This suggested that the three-dimensional architecture of the channel pore was maintained within the non-L-type alpha1A subunit. To predict the three-dimensional arrangement of the DHP-binding residues we exploited the X-ray structure of a recently crystallized bacterial K(+) channel (KcsA) as a template. Our model is based on the assumption that the Ca(2+) channel S5 and S6 segments closely resemble the KcsA transmembrane folding architecture. In the absence of three-dimensional structural data for the alpha1 subunit this is currently the most reasonable approach for modelling this drug-interaction domain. Our model predicts that the previously identified DHP-binding residues form a binding pocket large enough to co-ordinate a single DHP molecule. It also implies that the four homologous Ca(2+) channel repeats are arranged in a clockwise manner.

[Porcine stress syndrome and PSE meat: clinical symptoms, pathogenesis, etiology and animal rights aspects]

A review is given about the clinical symptoms, pathogenesis and aetiology of the porcine stress syndrome, furthermore aspects of animal welfare are discussed. The current breeding programmes of pig industry in Germany in many cases include animals with a mutation of the ryanodine-receptor (RYR-1)-gene--homozygous or heterozygous. This situation is the result of an intensive breeding of pigs during the last decades with the intention of increased lean carcass content and corresponding proceeds. The homozygous pigs are more stress susceptible (porcine stress syndrome) and produce meat of poor quality (PSE), which is also the case to some extend in heterozygous animals. The clinical symptoms of this muscle disease are characterised by a deficit of oxygen and a rapid glycolysis accompanied by a production of lactic acid and acidosis primarily in II B white muscle fibres. There is no doubt that a very close causal relation exists between the mutation of the RYR-1 and the porcine stress syndrome as well as the poor meat quality. The present knowledge of this disease, the genetic background, the physiology and pathophysiology of the mutation of the RYR-1 leads to the imperative conclusion to eliminate this mutated RYR-1 by selection of healthy pigs, which has been done successfully in other countries with important pig production. This conclusion is also supported by simple economic reasons because fertility, reproduction and daily weight gain are significantly reduced in stress susceptible pigs. Furthermore, it should be emphasised that regular breeding with the mutated RYR-1 is also a matter of animal welfare. The evident correlation between the mutated RYR-1 and the porcine stress syndrome, which includes degeneration of the muscle, pain and even life threatening malignant hyperthermia, can easily lead to the accusation in the public that diseased animals are used for pig meat production. Consequently, the authors would like to urge the breeding companies and the responsible authorities to discuss the problem with the intention to finish the current breeding programmes using animals with the mutated RYR-1 within a reasonable period of time.

Surface plasmon resonance studies prove the interaction of skeletal muscle sarcoplasmic reticular Ca(2+) release channel/ryanodine receptor with calsequestrin

A high affinity molecular interaction is demonstrated between calsequestrin and the sarcoplasmic reticular Ca(2+) release channel/ryanodine receptor (RyR) by surface plasmon resonance. K(D) values of 92 nM and 102 nM for the phosphorylated and dephosphorylated calsequestrin have been determined, respectively. Phosphorylation of calsequestrin seems not to influence this high affinity interaction, i.e. calsequestrin might always be bound to RyR. However, the phosphorylation state of calsequestrin determines the amount of Ca(2+) released from the lumen. Dephosphorylation of approximately 1% of the phosphorylated calsequestrin could be enough to activate the RyR channel half-maximally, as we have shown previously [Szegedi et al., Biochem. J. 337 (1999) 19].

Point mutations throughout the GLI3 gene cause Greig cephalopolysyndactyly syndrome

Greig cephalopolysyndactyly syndrome, characterized by craniofacial and limb anomalies (GCPS; MIM 175700), previously has been demonstrated to be associated with translocations as well as point mutations affecting one allele of the zinc finger gene GLI3. In addition to GCPS, Pallister-Hall syndrome (PHS; MIM 146510) and post-axial polydactyly type A (PAP-A; MIM 174200), two other disorders of human development, are caused by GLI3 mutations. In order to gain more insight into the mutational spectrum associated with a single phenotype, we report here the extension of the GLI3 mutation analysis to 24 new GCPS cases. We report the identification of 15 novel mutations present in one of the patient's GLI3 alleles. The mutations map throughout the coding gene regions. The majority are truncating mutations (nine of 15) that engender prematurely terminated protein products mostly but not exclusively N-terminally to or within the central region encoding the DNA-binding domain. Two missense and two splicing mutations mapping within the zinc finger motifs presumably also interfere with DNA binding. The five mutations identified within the protein regions C-terminal to the zinc fingers putatively affect additional functional properties of GLI3. In cell transfection experiments using fusions of the DNA-binding domain of yeast GAL4 to different segments of GLI3, transactivating capacity was assigned to two adjacent independent domains (TA(1)and TA(2)) in the C-terminal third of GLI3. Since these are the only functional domains affected by three C-terminally truncating mutations, we postulate that GCPS may be due either to haploinsufficiency resulting from the complete loss of one gene copy or to functional haploinsufficiency related to compromised properties of this transcription factor such as DNA binding and transactivation.

Polygraphic sleep criteria as predictors of successful aging: an exploratory longitudinal study

BACKGROUND

A cohort of 57 elderly healthy volunteers (34 male, 23 female) was studied in a sleep laboratory on four consecutive nights when their average age was 63.5 +/- 3.7 years. Thirty subjects (20 male, 10 female) were assessed 14 years later; 21 had either died in the meantime or were very ill, and 6 did not participate for other reasons.

METHODS

Two operationalizations of successful aging were applied: survival in relatively good health (30 survivors vs. 21 nonsurvivors), and cognitive competence as assessed in the survivors by means of tests of cognitive function.

RESULTS

Whereas none of the sleep characteristics determined at baseline distinguished the survivors from the nonsurvivors, several parameters [REM (rapid eye movement) sleep latency, REM density, and NREM (non-REM) shifts] were significantly correlated with one or more measures of cognitive functioning at follow-up. These polygraphic sleep parameters also distinguished a subgroup of cognitively fully competent subjects from those who, according to their performance in tests of cognitive function, could be considered as mildly demented.

CONCLUSIONS

While the REM latency and density findings support the theory of a functional link between brain cholinergic activity, timing, and density of REM sleep and cognitive functioning, the positive association between the number of NREM shifts at baseline and cognitive performance 14 years later is difficult to explain. It is suggested that the findings of the present study, in particular the potential predictive value of REM latency and REM density for cognitive functioning in the old, need replication in other subject samples followed for similar time periods.

[Rectovaginal fistulas in patients with Crohn disease--therapy and prognosis]

Perianal and especially rectovaginal fistulas in Crohn's disease represent a great therapeutic dilemma. Surgical intervention is mandatory in the impending destruction of the anal sphincter mechanism, weighed against the efficacy of the methods available. We report on the surgical approach in 25 women with rectovaginal fistula, concluding that either levator plasty or mucosal flap is the procedure of choice.

Calsequestrin: more than 'only' a luminal Ca2+ buffer inside the sarcoplasmic reticulum

In striated muscle, the sarcoplasmic reticulum (SR) Ca2+ release/ryanodine receptor (RyR) channel provides the pathway through which stored Ca2+ is released into the myoplasm during excitation-contraction coupling. Various luminal Ca2+-binding proteins are responsible for maintaining the free [Ca2+] at 10(-3)-10(-4) M in the SR lumen; in skeletal-muscle SR, it is mainly calsequestrin. Here we show that, depending on its phosphorylation state, calsequestrin selectively controls the RyR channel activity at 1 mM free luminal [Ca2+]. Calsequestrin exclusively in the dephosphorylated state enhanced the open probability by approx. 5-fold with a Hill coefficient (h) of 3.3, and increased the mean open time by about 2-fold, i.e. solely dephosphorylated calsequestrin regulates Ca2+ release from the SR. Because calsequestrin has been found to occur mainly in the phosphorylated state in the skeletal-muscle SR for the regulation of RyR channel activity, the dephosphorylation of calsequestrin would appear to be a quintessential physiological event.

[Disorders of sex development in dogs]

In two prepubertal dogs of female phenotype, a clitoral enlargement with a penile structure leading to recurring inflammation of the vagina was diagnosed. Progesterone, oestrogen and testosterone serum concentrations were radioimmunologically analysed. The histology of the penile structure, the gonads and the uterus was made via a hematoxylin-eosin staining method. The chromosome constitution being analysed by the method of Basur and Gilman (1964) was 2n = 78,XX. Regarding all results of this investigation the diagnose was XX-male. The development of this sexual disorder is discussed. The surgical removal of gonads and uterus and the excision of the enlarged clitoris is described.

Development of spatial memory and spatial orientation in preschoolers and primary school children

The present study addresses the question of what kind of information children use when orientating in new environments, if given proximal and distal landmarks, and how spatial memory develops in the investigated age groups. Ten 5-year-old, ten 7-year-old and ten 10-year-old children were presented with the 'Kiel Locomotor Maze', containing features of the Radial Arm Maze and the Morris Water Maze, in order to assess spatial memory and orientation. Children had to learn to approach baited locations only. Task difficulty was equated with respect to the children's age. Training was given until the children reached criterion. During testing, the maze configuration and response requirements were systematically altered, including response rotation, cue rotation, cue deletion and response rotation with cue deletion in order to assess the spatial strategies used by the children. During training and testing, working-memory errors (WM), reference-memory errors (RM) and working-reference memory errors (WR) were recorded. As expected, no difference between age groups appeared during training, thus confirming comparable task difficulty across age groups. During testing, age groups differed significantly with regard to the orientation strategy used. The 5-year-olds were bound to a cue strategy, orientating towards local, proximal cues. The 10-year-olds mastered all tasks, thus displaying a place strategy, being able to use distal cues for orientation, and were even able to do so after being rotated 180 degrees. The 7-year-olds proved to be at an age of transition: five of them were bound to a cue strategy, five children were able to adopt a place strategy. The differences in the orientation strategies used by children of different age groups was reflected by the sum of errors they made, also by RM. WM were found to be rare, especially in older children. We conclude that preschoolers use a cue strategy, that the development of place strategies occurs during primary school age and seems to be complete by the age of 10 years.

Effects of doxazosin and atenolol on atherothrombogenic risk profile in hypertensive middle-aged men

The alpha-blockers prazosin and doxazosin reduce hypertriglyceridemia (HTG) and increase serum levels of high-density lipoprotein (HDL)-cholesterol, whereas beta-blockers such as atenolol have the opposite effect. As HTG is associated with reduced fibrinolysis and hypercoagulability, we investigated the effects of doxazosin and atenolol on serum lipids and hemostatic factors in hypertensive men with an atherothrombogenic risk profile. The study was randomized and open, but blinded to investigator of biochemical results. Forty-five men (mean age, 44.5 years) with central obesity [median body-mass index (BMI), 28 kg/m2] and moderate hypertension [median diastolic blood pressure (DBP), 104.5 mm Hg] were treated with atenolol (n = 22) or doxazosin (n = 23) for 22 weeks, after which changes in between-group differences from baseline were estimated. After intervention, significant between-group differences in favor of doxazosin were found: lower triglycerides (p = 0.008) and higher HDL cholesterol (p = 0.036); furthermore, improvement of fibrinolysis: lower plasminogen activator inhibitor-1 (PAI-1) activity (p = 0.012), higher tissue plasminogen activator (tPA) activity after venous occlusion (VO); and higher levels of serum D-dimer, both unstimulated (p = 0.0016) and after VO (p = 0.0032). In addition, lower levels of serum testosterone were found in the atenolol group (p = 0.0016). A profile with reduced HTG, increased HDL cholesterol, and improved fibrinolysis was obtained with doxazosin when compared with atenolol. Furthermore, the observed decrease in serum testosterone on atenolol treatment would rather favor long-term treatment with doxazosin in this study population.

Health care applications of complexity science. Life at the edge of chaos

The authors explore complexity science, a relatively new field of inquiry, which holds for both clinicians and health care leaders the real possibility of stimulating fresh insights and approaches to health and medical care-both its provision and its organization. Two case studies are presented to illustrate how complexity theory can provide health care leaders with a new perspective on how to address the myriad challenges they confront daily: (1) a patient with dissociative identity disorder; and (2) a physician task group charged to advise on hospital medical staff reorganization and governance. These case studies help clinicians and leaders of health care organizations understand how complexity: (1) may be relevant, even helpful, as they consider difficult challenges in both patient and organizational management; and (2) might emerge as a synthesizing force as they face the extraordinarily complicated task of jointly creating integrated health care systems. A resource section is provided for those who may wish to further pursue the topic.

Enhancing accurate assessment of periodontal disease by improving radiographic interpretation

One of the most difficult areas of radiographic interpretation is periodontal assessment--an area critical to the success of the role of today's dental hygienists charged with the responsibility of evaluation and treatment of periodontal disease. The accurate evaluation and interpretation of radiographs, used by dental hygienists in conjunction with a clinical periodontal examination, is essential for effective planning and provision of nonsurgical periodontal therapy and appropriate referral as necessary. Definitive assessments require high quality radiographs with the minimum of distortion. Currently, bitewing radiographs are the technique of choice for evaluation of periodontal structures, with the use of vertical bitewings (which allow the clinician to view osseous tissue in both arches simultaneously) recommended as disease progresses. Clinicians have complete control over the various technical factors which may affect the processed radiograph and consequently the periodontal interpretation. The procedures highlighted in this article will result in good diagnostic quality with the minimum of exposure to the patient. Accurate radiographic assessment also depends upon the ability of the hygienist to recognize the appearance of normal periodontal tissues as well as the periodontium in a diseased state. Because in the early stages of disease radiographic changes are difficult to observe, a keen, well-trained eye is required to see the slight alterations occurring in the periodontium. This article reviews the radiographic appearance of normal tissues and the generally accepted sequence of radiographic changes associated with periodontitis according to the American Academy of Periodontology (AAP).

Serine phosphorylation site of the 46-kDa mannose 6-phosphate receptor is required for transport to the plasma membrane in Madin-Darby canine kidney and mouse fibroblast cells

Up to 4% of the human 46-kDa mannose 6-phosphate receptor (MPR46) expressed in Madin-Darby canine kidney (MDCK) cells are localized at the cell surface. At steady state, the expression of MPR46 on the apical surface of filter-grown MDCK cells is about sixfold lower than on the basolateral surface. The cytoplasmic domain of the MPR46 is phosphorylated on serine 56 at low stoichiometry. By expressing mutant MPR46 we have shown that the MPR46 phosphorylation site is required for delivery to the plasma membrane. In addition, mutant MPR46 expressed in MPR-deficient mouse embryonic fibroblasts were not detected at the cell surface and their ability to sort newly synthesized cathepsin D was not altered. Since the loss of MPR46 phosphorylation correlates with the lack of cell surface expression, phosphorylation of serine 56 may either function as a direct plasma membrane targeting signal or inhibit MPR46 recycling from endosomes to Golgi, resulting in trafficking to the cell surface.

'Semifree-floating' treatment: a simple and fast method to process consecutive sections for immunohistochemistry and neuronal tracing

A method is described which allows for histochemical processing of thick (50-200 microm) and consecutive sections of neural tissue, a prerequisite for many neuroanatomical studies. Two examples are given: (A) biotin-dextran-amine (BDA) tracing of neuronal connections in 50-100 microm thick vibratome sections of the adult rat brain and (B) immunohistochemical analysis of tyrosine hydroxylase-positive bulbospinal fibers in 50 microm thick cryosections of spinal cord.