Derivation of Highly Predictive 3D-QSAR Models for hERG Channel Blockers Based on the Quantum Artificial Neural Network Algorithm

The hERG potassium channel serves as an annexed target for drug discovery because the associated off-target inhibitory activity may cause serious cardiotoxicity. Quantitative structure-activity relationship (QSAR) models were developed to predict inhibitory activities against the hERG potassium channel, utilizing the three-dimensional (3D) distribution of quantum mechanical electrostatic potential (ESP) as the molecular descriptor. To prepare the optimal atomic coordinates of dataset molecules, pairwise 3D structural alignments were carried out in order for the quantum mechanical cross correlation between the template and other molecules to be maximized. This alignment method stands out from the common atom-by-atom matching technique, as it can handle structurally diverse molecules as effectively as chemical derivatives that share an identical scaffold. The alignment problem prevalent in 3D-QSAR methods was ameliorated substantially by dividing the dataset molecules into seven subsets, each of which contained molecules with similar molecular weights. Using an artificial neural network algorithm to find the functional relationship between the quantum mechanical ESP descriptors and the experimental hERG inhibitory activities, highly predictive 3D-QSAR models were derived for all seven molecular subsets to the extent that the squared correlation coefficients exceeded 0.79. Given their simplicity in model development and strong predictability, the 3D-QSAR models developed in this study are expected to function as an effective virtual screening tool for assessing the potential cardiotoxicity of drug candidate molecules.

Quantum Artificial Neural Network Approach to Derive a Highly Predictive 3D-QSAR Model for Blood-Brain Barrier Passage

A successful passage of the blood–brain barrier (BBB) is an essential prerequisite for the drug molecules designed to act on the central nervous system. The logarithm of blood–brain partitioning (LogBB) has served as an effective index of molecular BBB permeability. Using the three-dimensional (3D) distribution of the molecular electrostatic potential (ESP) as the numerical descriptor, a quantitative structure-activity relationship (QSAR) model termed AlphaQ was derived to predict the molecular LogBB values. To obtain the optimal atomic coordinates of the molecules under investigation, the pairwise 3D structural alignments were conducted in such a way to maximize the quantum mechanical cross correlation between the template and a target molecule. This alignment method has the advantage over the conventional atom-by-atom matching protocol in that the structurally diverse molecules can be analyzed as rigorously as the chemical derivatives with the same scaffold. The inaccuracy problem in the 3D structural alignment was alleviated in a large part by categorizing the molecules into the eight subsets according to the molecular weight. By applying the artificial neural network algorithm to associate the fully quantum mechanical ESP descriptors with the extensive experimental LogBB data, a highly predictive 3D-QSAR model was derived for each molecular subset with a squared correlation coefficient larger than 0.8. Due to the simplicity in model building and the high predictability, AlphaQ is anticipated to serve as an effective computational screening tool for molecular BBB permeability.

Development and application of a comprehensive machine learning program for predicting molecular biochemical and pharmacological properties

We establish a comprehensive quantitative structure-activity relationship (QSAR) model termed AlphaQ through the machine learning algorithm to associate the fully quantum mechanical molecular descriptors with various biochemical and pharmacological properties. Preliminarily, a novel method for molecular structural alignments was developed in such a way to maximize the quantum mechanical cross correlations among the molecules. Besides the improvement of structural alignments, three-dimensional (3D) distribution of the molecular electrostatic potential was introduced as the unique numerical descriptor for individual molecules. These dual modifications lead to a substantial accuracy enhancement in multifarious 3D-QSAR prediction models of AlphaQ. Most remarkably, AlphaQ has been proven to be applicable to structurally diverse molecules to the extent that it outperforms the conventional QSAR methods in estimating the inhibitory activity against thrombin, the water-cyclohexane distribution coefficient, the permeability across the membrane of the Caco-2 cell, and the metabolic stability in human liver microsomes. Due to the simplicity in model building and the high predictive capability for varying biochemical and pharmacological properties, AlphaQ is anticipated to serve as a valuable screening tool at both early and late stages of drug discovery.

Effectiveness of anti-osteoporotic drugs to prevent secondary fragility fractures: systematic review and meta-analysis

Patients with osteoporotic fractures have an increased risk for secondary fractures. However, a rigorous study that assesses the effectiveness of individual osteoporotic drugs in preventing subsequent fractures is lacking. The purpose of this review was to analyze the effectiveness of anti-osteoporotic drugs in preventing secondary fractures. We searched for randomized controlled trials that showed the incidence of secondary fractures while using anti-osteoporotic drugs (bisphosphonates, selective estrogen receptor modulators, parathyroid hormone (PTH), or calcitonin) in MEDLINE, Embase.com , and Cochrane Central Register databases. We estimated risk ratios (RR) and numbers needed to treat (NNT) to prevent secondary fractures. Twenty-six studies met our eligibility criteria. There was a significant reduction in RR (0.38-0.77) after the use of anti-osteoporotic drugs for secondary vertebral fractures. Bisphosphonates and PTH significantly reduced the risk of a secondary non-vertebral fracture (RR 0.59 and 0.64). PTH needed the fewest number of patients to be treated to prevent a secondary vertebral fracture (NNT: 56). Our study demonstrated the effectiveness of anti-osteoporotic agents included in our systematic review in preventing secondary vertebral fractures. Bisphosphonates and PTH were most effective in preventing non-vertebral fractures. We suggest that clinicians should prescribe these drugs to prevent secondary vertebral/non-vertebral fractures.

Proteolytic degradation and potential role of onconeural protein cdr2 in neurodegeneration

Cerebellar degeneration-related protein 2 (cdr2) is expressed in the central nervous system, and its ectopic expression in tumor cells of patients with gynecological malignancies elicits immune responses by cdr2-specific autoantibodies and T lymphocytes, leading to neurological symptoms. However, little is known about the regulation and function of cdr2 in neurodegenerative diseases. Because we found that cdr2 is highly expressed in the midbrain, we investigated the role of cdr2 in experimental models of Parkinson's disease (PD). We found that cdr2 levels were significantly reduced after stereotaxic injection of 1-methyl-4-phenylpyridinium (MPP(+)) into the striatum. cdr2 levels were also decreased in the brains of post-mortem PD patients. Using primary cultures of mesencephalic neurons and MN9D cells, we confirmed that MPP(+) reduces cdr2 in tyrosine hydroxylase-positive dopaminergic neuronal cells. The MPP(+)-induced decrease of cdr2 was primarily caused by calpain- and ubiquitin proteasome system-mediated degradation, and cotreatment with pharmacological inhibitors of these enzymes or overexpression of calcium-binding protein rendered cells less vulnerable to MPP(+)-mediated cytotoxicity. Consequently, overexpression of cdr2 rescued cells from MPP(+)-induced cytotoxicity, whereas knockdown of cdr2 accelerated toxicity. Collectively, our findings provide insights into the novel regulatory mechanism and potentially protective role of onconeural protein during dopaminergic neurodegeneration.

The influence of androstadienone during psychosocial stress is modulated by gender, trait anxiety and subjective stress: An fMRI study

Androstadienone (ANDR), a bodily secreted steroid compound, is a socially relevant chemosignal that modulates subjective and (neuro)physiological responses, predominantly in females. The impact of ANDR on stress responses in males and females has not been explored. Therefore, this fMRI study aimed to examine psychosocial stress reactions induced by mental arithmetic and social evaluation on behavioral and hormonal levels (46 participants: 15 naturally cycling females in their early follicular phase (EF), 15 females on hormonal contraceptives (HC) and 16 males); and on a neural level (40 participants: 13 EF-females, 13 HC-females and 14 males) in an ANDR and placebo treatment repeated-measures design. While no gender differences emerged in subjective ratings and performance during stress, neural activation patterns differed significantly. Besides, ANDR attenuated the post-stress increase of negative mood in all participants. Region of interest analyses showed that irrespective of treatment, males showed stronger activation of the dorsolateral prefrontal cortex (DLPFC) than females. At the whole brain level, gender differences emerged indicating stronger fronto-parietal activation in males compared to HC-females on both treatments. Males showed stronger visual and fusiform activation than EF-females under ANDR. Both female groups did not show stronger activation than males. Further, error ratio in the ANDR-stress condition was positively associated with their post-stress cortisol level and increase in subjective stress in males; and male DLPFC activity in the ANDR-stress condition was negatively associated with trait anxiety. Surprisingly, compared to HC-females, EF-female only showed stronger activation of arousal-related areas under placebo treatment. Taken together, these findings suggest that the male stress reaction under social evaluative threat was stronger than female stress reactions as a function of ANDR. More specifically, this effect on behavioral and neural stress reactions seems to depend on trait anxiety in males only. The study highlights the significance of a chemosignal in enhancing social threat that may facilitate adaptive stress responses.

Accuracy enhancement in the estimation of molecular hydration free energies by implementing the intramolecular hydrogen bond effects

Background

The formation of intramolecular hydrogen bonds (IHBs) may induce the remarkable changes in molecular physicochemical properties. Within the framework of the extended solvent-contact model, we investigate the effect of implementing the IHB interactions on the accuracy in estimating the molecular hydration free energies.

Results

The performances of hydration free energy functions including and excluding the IHB parameters are compared using the molecules distributed for SAMPL4 blind prediction challenge and those in Free Solvation Database (FSD). The calculated hydration free energies with IHB effects are found to be in considerably better agreement with the experimental data than those without them. For example, the root mean square error of the estimation decreases from 2.56 to 1.66 and from 1.73 to 1.54 kcal/mol for SAMPL4 and FSD molecules, respectively, due to the extension of atomic parameter space to cope with IHBs.

Conclusions

These improvements are made possible by reducing the overestimation of attractive interactions between water and the solute molecules involving IHBs. The modified hydration free energy function is thus anticipated to be useful for estimating the desolvation cost for various organic molecules.

Electronic supplementary material

The online version of this article (doi:10.1186/s13321-015-0106-2) contains supplementary material, which is available to authorized users.

Mortality after distal radial fractures in the Medicare population

The occurrence of a low energy fracture of the distal radius increases the risk for another, more serious fracture, such as a proximal femoral fracture. Early mortality after a proximal femoral fracture has been widely studied, but the association between a distal radial fracture and mortality is unknown. The date of death for all Medicare beneficiaries who sustained an isolated distal radial fracture in 2007 was determined using Medicare Vital Statistics files. The adjusted mortality rate for each age-sex group was calculated and compared with published US mortality tables. Distal radial fractures were not associated with an increased mortality rate. In fact, beneficiaries had a significantly lower mortality rate after distal radial fractures than the general population. This may be related to the injured beneficiaries' involvement in the healthcare system. Mortality rate did not vary significantly based on time from injury. Our results indicate that any mortality is unlikely to be attributable to the distal radial fracture or its treatment. Level of evidence: III.

The impact of abnormal muscle tone from hemiplegia on reclining wheelchair positioning: a sliding and pressure evaluation

BACKGROUND

Little is known about the influence of existing muscle tone abnormality on the sitting posture of stroke patients in reclining wheelchairs.

AIM

To investigate the impact of muscle tone abnormality from hemiplegia on the forward sliding and pressure of stroke patients while sitting in reclining wheelchairs.

DESIGN

Experimental study.

SETTING

The Assistive Devices/Technology Center at the Rehabilitation Department of hospital.

POPULATION

14 able-bodied elders and nonambulatory elderly stroke patients with flaccid (N.=12) or spastic hemiplegia (N.=13) participated in this study. Of the 12 patients with flaccid hemiplegia, 8 suffered from left-sided hemiplegia and 4 from right-sided hemiplegia. Of the 13 patients with spastic hemiplegia, 6 suffered from left-sided hemiplegia and 7 from right-sided hemiplegia.

METHODS

We performed 3 reclining cycles in wheelchairs with conventional seats and V-shaped seats for each participant. The sliding along the backrest (BS) plane and the seat (SS) plane, mean sitting pressure (MP), and sacral peak pressure (SPP) of the participants were recorded. The Kruskal-Wallis test was used to compare the difference in BS, SS, MP, and SPP between able-bodied elders and stroke patients.

RESULTS

The BS, SS, and SPP during repetitive reclining were generally greatest in flaccid hemiplegic participants, followed by spastic hemiplegic participants, and finally by able-bodied participants. There was no significant difference in MP among three subject groups on both conventional seats and V-shaped seats in most comparisons. Able-bodied participants' buttocks tended to slide forward on conventional seats but backward on V-shaped seats, whereas hemiplegic participants' buttocks slid forward on both seat types.

CONCLUSION

Stroke patients with flaccid hemiplegia are the most vulnerable to sacral sitting and higher sacral pressure in reclining wheelchairs, followed by patients with spastic hemiplegia. There is a difference in the displacement pattern between participants with normal muscle tone and those with abnormal muscle tone during wheelchair positioning. People who have hemiplegia with spasticity do not have incremental forward sliding with repetitive reclining in the same way as those who have a flaccid hemiplegia.

CLINICAL REHABILITATION IMPACT

The findings are valuable for wheelchair prescription and caregiver education.

Wound healing with medications for rheumatoid arthritis in hand surgery

Introduction. Medications used to treat rheumatoid arthritis, such as corticosteroids, disease-modifying agents (DMARDs), and injectable biological agents (anti-TNFα), may have widespread effects on wound healing. In hand surgery, it is important to balance the risks of poor wound healing from continuing a medication against the risks of a flare of rheumatoid arthritis if a drug is temporarily discontinued. Materials and Methods. A United Kingdom (UK) group of 28 patients had metacarpophalangeal joint replacement surgery in 35 hands (140 wounds). All medication for rheumatoid arthritis was continued perioperatively, except for the injectable biological agents. Results. There were no instances of wound dehiscence or deep infection and only one episode of minor superficial infection. Conclusions. We conclude that provided care is taken to identify and treat any problems promptly, it is appropriate to continue most antirheumatoid medications in the perioperative period during hand surgery to reduce the risk of destabilising the patients' overall rheumatoid disease control.

Acute ophthalmoplegia (without ataxia) associated with anti-GQ1b antibody

BACKGROUND

Anti-GQ1b antibody has been found in Miller Fisher syndrome (MFS), Guillain-Barré syndrome (GBS) with ophthalmoplegia, Bickerstaff brainstem encephalitis (BBE), and acute ophthalmoplegia without ataxia (AO). The aim of this study was to determine the clinical features of AO associated with anti-GQ1b antibody.

METHODS

We retrospectively collected 34 patients with anti-GQ1b antibody syndrome. Of these patients, 31 patients had ophthalmoplegia. The patients with ophthalmoplegia were classified into MFS (n = 13), AO (n = 11), GBS with ophthalmoplegia (n = 6), and BBE (n = 1). We analyzed clinical features and patterns of external and internal ophthalmoplegia of AO, and neuro-ophthalmologic findings were compared with those of other anti-GQ1b syndromes with ophthalmoplegia.

RESULTS

AO was observed in 11 (32.4%) of the 34 patients with anti-GQ1b antibody. External ophthalmoparesis was present in all the patients and included mixed horizontal-vertical (n = 7), pure horizontal (n = 3), and pure vertical gaze palsy (n = 1). Binocular involvement was common, but unilateral ophthalmoparesis was also observed in 27.3%. Other findings included ptosis (n = 5, 45.5%) and internal ophthalmoplegia (n = 6, 54.5%). Other anti-GQ1b antibody syndromes had prominent neurologic signs including ataxia, weakness, and facial palsy in addition to ophthalmoplegia. The patterns of neuro-ophthalmologic findings did not differ between AO and other anti-GQ1b antibody syndromes with ophthalmoplegia.

CONCLUSIONS

Acute ophthalmoplegia (AO) commonly occurs in anti-GQ1b antibody syndrome and manifests as various combinations of external and internal ophthalmoplegia. Internal ophthalmoplegia is fairly common and unilateral involvement may occur in AO.

A case of unilateral hemispheric encephalitis

Herein we report a case of encephalitis involving the unilateral hemisphere, with a clinical course different from that of Rasmussen syndrome. A 44-year-old man visited us because of headache and language abnormality. Cerebrospinal fluid examination showed lymphocytosis with increased level of protein. Brain MRI showed abnormal findings limited to the unilateral hemisphere. The symptoms and signs improved without any specific antiviral treatment in a week. However, language disturbance and right hemiparesis developed after a week. Steroid therapy was effective. He recovered without any neurologic sequelae. Our case was unusual encephalitis involving the unilateral hemisphere, which was benign and steroid-responsive.

Magnetic resonance microscopic imaging based on high-order intermolecular multiple-quantum coherences

Most imaging studies using intermolecular multiple-quantum coherences (iMQCs) have focused on the two-spin dipolar interactions--zero and double quantum coherences. Here, we report the results of various experimental studies to assess the feasibility of magnetic resonance microscopy with high-order iMQCs in model systems at 7 and 14 T. Experimental results demonstrated that the iMQC microscopic images with high coherence orders are readily observable at high field and have unique contrast depending on the sample microstructure and coherence order.

Fluorogenic Hg2+-Selective Chemodosimeter Derived from 8-Hydroxyquinoline

[reaction: see text] A new thioamide derivative of 8-hydroxyquinoline-benzothiazole was prepared, and its fluorogenic chemodosimetric behaviors toward transition-metal ions were investigated. The thioamide derivative showed highly Hg2+-selective fluorescence enhancing properties (167-fold) in 30% aqueous acetonitrile solution. The selective and sensitive signaling behaviors were found to originate from the Hg2+ ion induced transformation of the very weak fluorescent thioamide derivative into a highly fluorescent amide analogue.

Assessing outcome after hand surgery: the current state

An overview of the current state of outcome measurement after hand surgery is presented. The paper focuses on the development, application and strengths and weaknesses of it also reviews the existing questionnaires and suggests recommendations for use in research or clinical practice.

Association between maternal diabetes mellitus and newborn oral cleft

Diabetes mellitus has been implicated in several studies as a possible etiological factor of various congenital anomalies. Oral clefts are common congenital malformations that may severely affect the quality of life. The authors conducted a population-based case-control study using the 1996 National Center for Health Statistics United States Natality database to investigate whether maternal diabetes mellitus is a risk factor (p < 0.05) for having a newborn with an oral cleft. The patients consisted of 2,207 live births with cleft lip/palate, and the control subjects were 4,414 randomly selected live births, excluding those with other congenital defects. After adjusting for potential confounding variables, diabetic mothers were found to be 1.352 times (95% confidence interval, 1.004-1.821; p < 0.05) more likely than nondiabetic mothers to have a newborn with cleft lip/palate. In counseling expectant mothers, early glycemic control may be an important factor in decreasing the incidence of this congenital anomaly.

Is negative ulnar variance a risk factor for Kienböck's disease? A meta-analysis

Current treatment for Kienbock's disease using joint-leveling procedures is based on the hypothesis that the disease is caused by negative ulnar variance. The authors conducted a meta-analysis to evaluate this hypothesis, and assessed the quality of available published studies. They searched MEDLINE to collect literature that evaluated this association. Only 3 of 18 collected studies had sufficient data or study design to meet their inclusion criteria. A summary odds ratio (OR) calculated using a conservative random-effect method showed that the odds of Kienböck's disease was 3.10 times more likely for those with negative ulnar variance than those with positive or neutral ulnar variance, but this was not significant (95% confidence interval, 0.95-10.05; p = 0.06). The combined OR was unstable because of marked heterogeneity across the studies. This meta-analysis reveals that there is insufficient data to support a significant (p < 0.05) association between negative ulnar variance and Kienbock's disease.

Protein kinase Dyrk1 activates cAMP response element-binding protein during neuronal differentiation in hippocampal progenitor cells

Dyrk is a dual specific protein kinase thought to be involved in normal embryo neurogenesis and brain development. Defects/imperfections in this kinase have been suggested to play an important role in the mental retardation of patients with Down's syndrome. The transcriptional factor cAMP response element-binding protein (CREB) has been implicated in the formation of many types of synaptic plasticity, such as learning and memory. In the present study we show that Dyrk1 activity is markedly induced during the differentiation of immortalized hippocampal progenitor (H19-7) cells. The addition of a neurogenic factor, basic fibroblast growth factor, to the H19-7 cells results in an increased specific binding of Dyrk1 to active CREB. In addition, Dyrk1 directly phosphorylates CREB, leading to the stimulation of subsequent CRE-mediated gene transcription during the neuronal differentiation in H19-7 cells. Blockade of Dyrk1 activation significantly inhibits the neurite outgrowth as well as CREB phosphorylation induced by basic fibroblast growth factor. These findings suggest that Dyrk1 activation and subsequent CREB phosphorylation is important in the neuronal differentiation of central nervous system hippocampal cells.

Inhibitory effect of dry needling on the spontaneous electrical activity recorded from myofascial trigger spots of rabbit skeletal muscle

OBJECTIVE

Dry needling of myofascial trigger points can relieve myofascial pain if local twitch responses are elicited during needling. Spontaneous electrical activity (SEA) recorded from an active locus in a myofascial trigger point region has been used to assess the myofascial trigger point sensitivity. This study was to investigate the effect of dry needling on SEA.

DESIGN

Nine adult New Zealand rabbits were studied. Dry needling with rapid insertion into multiple sites within the myofascial trigger spot region was performed to the biceps femoris muscle to elicit sufficient local twitch responses. Very slow needle insertion with minimal local twitch response elicitation was conducted to the other biceps femoris muscle for the control study. SEA was recorded from 15 different active loci of the myofascial trigger spot before and immediately after treatment for both sides. The raw data of 1-sec SEA were rectified and integrated to calculate the average integrated value of SEA.

RESULTS

Seven of nine rabbits demonstrated significantly lower normalized average integrated value of SEA in the treatment side compared with the control side (P < 0.05). The results of two-way analysis of variance show that the mean of the normalized average integrated value of SEA in the treatment group (0.565 +/- 0.113) is significantly (P < 0.05) lower than that of the control (0.983 +/- 0.121).

CONCLUSIONS

Dry needling of the myofascial trigger spot is effective in diminishing SEA if local twitch responses are elicited. The local twitch response elicitation, other than trauma effects of needling, seems to be the primary inhibitory factor on SEA during dry needling.

Differential activation of phospholipases by mitogenic EGF and neurogenic PDGF in immortalized hippocampal stem cell lines

In several neuronal systems, nerve growth factor (NGF) and platelet-derived growth factor (PDGF) act as neurogenic agents, whereas epidermal growth factor (EGF) acts as a mitogenic agent. Hippocampal stem cell lines (HiB5) immortalized by the expression of a temperature-sensitive SV40 large T antigen also respond differentially to EGF and PDGF. While EGF treatment at the permissive temperature induces proliferation, the addition of PDGF induces differentiation at the non-permissive temperature. However, the mechanism responsible for these different cellular fates has not been clearly elucidated. In order to clarify possible critical signaling events leading to these distinct cellular outcomes, we examined whether either EGF or PDGF differentially induces the activation of phospholipases, such as phospholipase A(2) (PLA(2)), C (PLC), or D (PLD). Although EGF stimulation did not induce phospholipases, PDGF caused a rapid and transient activation of PLC and PLD, but not PLA(2). When the activation of PLC or PLD was blocked, the neurite outgrowth induced by PDGF was significantly inhibited. Although the activation of PLD occurred faster than PLC, blocking of PLD activity by transient expression of lipase-inactive mutants did not inhibit the induction of PLC activity by PDGF. These results suggest that the differential activation of phospholipases may play an important role in signal transduction by mitogenic EGF and neurotrophic PDGF in HiB5 neuronal hippocampal stem cells. In particular, the activation of phospholipase C and D may contribute to neuronal differentiation by neurogenic PDGF in the HiB5 cells.

Use of three free flaps based on a single vascular pedicle for complex hand reconstruction in an electrical burn injury: a case report

The use of conjoint flaps based on the dorsalis pedis artery enabled a transfer of 3 free flaps-dorsalis pedis flap, fillet flap of the second toe, and trimmed large toe-to reconstruct a severely traumatized hand in a 12-year-old girl. High-voltage electrical burn injury had caused a large wound over the volar wrist and exposed the flexor tendons and median/ulnar nerves. In addition, she suffered a partial loss of the thumb and had an open wound at the base of the index finger. The application of the conjoint flaps restored hand function in a one-stage procedure.

The frequency and epidemiology of hand and forearm fractures in the United States

The purpose of this study was to estimate the frequency and describe the epidemiology of hand and forearm fractures in the United States. We extracted cases with ICD-9-CM diagnostic codes of 813.0 to 817.1 from the 1998 National Hospital Ambulatory Medical Care Survey. In 1998 there were 1,465,874 estimated cases of hand/forearm fractures, accounting for 1.5% of all emergency department cases. Radius and/or ulna fractures comprised the largest proportion of fractures (44%). The most affected age group was 5 to 14 years of age (26%). Private insurance paid for 49% of the cases. Most of the fractures occurred at home (30%); the street/highway was the second most likely fracture location (14%). Accidental falls caused the majority (47%) of fractures. Large database analysis provides important information that can be used to target interventions toward vulnerable populations and to allocate adequate resources for treating upper extremity fractures.

Zn2+-induced ERK activation mediated by reactive oxygen species causes cell death in differentiated PC12 cells

Recent studies have provided evidence that Zn2+ plays a crucial role in ischemia- and seizure-induced neuronal death. However, the intracellular signaling pathways involved in Zn2+-induced cell death are largely unknown. In the present study, we investigated the roles of mitogen-activated protein kinases (MAPKs), such as c-Jun N-terminal kinase (JNK), p38 MAPK and extracellular signal-regulated kinase (ERK), and of reactive oxygen species (ROS) in Zn2+-induced cell death using differentiated PC12 cells. Intracellular accumulation of Zn2+ induced by the combined application of pyrithione (5 microM), a Zn2+ ionophore, and Zn2+ (10 microM) caused cell death and activated JNK and ERK, but not p38 MAPK. Preventing JNK activation by the expression of dominant negative SEK1 (SEKAL) did not attenuate Zn2+-induced cell death, whereas the inhibition of ERK with PD98059 and the expression of dominant negative Ras mutant (RasN17) significantly prevented cell death. Inhibition of protein kinase C (PKC) and phosphatidylinositol-3 kinase had little effect on Zn2+-induced ERK activation. Intracellular Zn2+ accumulation resulted in the generation of ROS, and antioxidants prevented both the ERK activation and the cell death induced by Zn2+. Therefore, we conclude that although Zn2+ activates JNK and ERK, only ERK contributes to Zn2+-induced cell death, and that ERK activation is mediated by ROS via the Ras/Raf/MEK/ERK signaling pathway.

Multiple ligand interaction of alpha-synuclein produced various forms of protein aggregates in the presence of Abeta25-35, copper, and eosin

Various protein aggregates of alpha-synuclein developed by way of the common protein self-oligomerization in the presence of Abeta25-35, copper, and eosin were examined. All the aggregates exhibited congo red birefringence although the actual amounts of the aggregates were varied as determined by thioflavin T binding fluorescence. When their morphologies were analyzed in relation to in vitro cytotoxicity, the smallest granular aggregates obtained with copper exhibited the highest cytotoxicity, while the fibrous structures by eosin did not affect the cell.

Induction of neuronal cell death by Rab5A-dependent endocytosis of alpha-synuclein

The presynaptic alpha-synuclein is a prime suspect for contributing to Lewy pathology and clinical aspects of diseases, including Parkinson's disease, dementia with Lewy bodies, and a Lewy body variant of Alzheimer's disease. Here we examined the pathogenic mechanism of neuronal cell death induced by alpha-synuclein. The exogenous addition of alpha-synuclein caused a marked decrease of cell viability in primary and immortalized neuronal cells. The neuronal cell death appeared to be correlated with the Rab5A-specific endocytosis of alpha-synuclein that subsequently caused the formation of Lewy body-like intracytoplasmic inclusions. This was further supported by the fact that the expression of GTPase-deficient Rab5A resulted in a significant decrease of its cytotoxicity as a result of incomplete endocytosis of alpha-synuclein.

The behavior of a poly(aniline) solid contact pH selective electrode based on N,N,N',N'-tetrabenzylethanediamine ionophore

A hydrogen ion-selective solid-contact electrode based on N,N,N',N'-tetrabenzylethanediamine has shown the best Nernstian slope and selectivity and the widest response range in a Tris buffered pH sample solution. Its linear dynamic range was pH 3.50-11.94, and the Nernstian slope showed 52.1 mV/pH (at 20 +/- 0.2 degrees C). When it was directly applied to human whole blood (in pH range 6.0-8.5) we could obtain the same satisfying results. This electrode continuously contacted a Tris 7.47 buffered solution, human whole blood and a hydrofluoric acid solution for one month without any loss of performance. Also, hydrofluoric acid did not influence the surface of this electrode, and thus it was maintained without showing any changes in potentials after being used in a hydrofluoric acid solution. The standard deviation in the determined e.m.f. differences was 1.5 mV (N = 5) for Tris buffer solutions of pH 6.5 and 1.1 mV at a Tris buffer solutions of pH 8.5. The 90% response time of the electrodes obtained by injecting of hydrochloric acid into the Tris buffer sample solution was less than 10 s. Especially, in the this paper, with these potential response characteristics of hydrogen ion selective poly(aniline) solid contact electrode, we have also presented the pH response mechanism of this electrode and the role of poly(aniline) and a doped anion in a poly(aniline) layer.

Basic fibroblast growth factor-induced activation of novel CREB kinase during the differentiation of immortalized hippocampal cells

Growth factors bind to their specific receptors on the responsive cell surface and thereby initiate dramatic changes in the proliferation, differentiation, and survival of their target cells. In the present study we have examined the mechanism by which growth factor-induced signals are propagated to the nucleus, leading to the activation of transcription factor, cis-acting cAMP response element (CRE)-binding protein (CREB), in immortalized hippocampal progenitor cells (H19-7). During the differentiation of H19-7 cells by basic fibroblast growth factor (bFGF) a critical regulatory Ser(133) residue of CREB was phosphorylated followed by an increase of CRE-mediated gene transcription. Expression of S133A CREB mutants blocked the differentiation of H19-7 cells by bFGF. Although the kinetics of CREB phosphorylation by EGF was transient, bFGF induced a prolonged pattern of CREB phosphorylation. Interestingly, bFGF-induced CREB phosphorylation and subsequent CRE-mediated gene transcription is not likely to be mediated by any of previously known signaling pathways that lead to phosphorylation of CREB, such as mitogen-activated protein kinases, protein kinase A, protein kinase C, phosphatidylinositol 3-kinase-p70(S6K), calcium/calmodulin dependent protein kinase, and casein kinase 2. By using in vitro in gel kinase assay the presence of a novel 120-kDa bFGF-inducible CREB kinase was identified. These findings identify a new growth factor-activated signaling pathway that regulates gene expression at the CRE.

Intracellular calcium mobilization induces immediate early gene pip92 via Src and mitogen-activated protein kinase in immortalized hippocampal cells

Regulation of intracellular calcium levels plays a central role in cell survival, proliferation, and differentiation. A cell-permeable, tumor-promoting thapsigargin elevates the intracellular calcium levels by inhibiting endoplasmic reticulum Ca(2+)-ATPase. The Src-tyrosine kinase family is involved in a broad range of cellular responses ranging from cell growth and cytoskeletal rearrangement to differentiation. The immediate early gene pip92 is induced in neuronal cell death as well as cell growth and differentiation. To resolve the molecular mechanism of cell growth by intracellular calcium mobilization, we have examined the effect of thapsigargin and subsequent intracellular calcium influx on pip92 expression in immortalized rat hippocampal H19-7 cells. An increase of intracellular calcium ion levels induced by thapsigargin stimulated the expression of pip92 in H19-7 cells. Transient transfection of the cells with kinase-inactive mitogen-activated protein kinase kinase (MEK) and Src kinase or pretreatment with the chemical MEK inhibitor PD98059 significantly inhibited pip92 expression induced by thapsigargin. When constitutively active v-Src or MEK was overexpressed, the transcriptional activity of the pip92 gene was markedly increased. Dominant inhibitory Raf-1 blocked the transcriptional activity of pip92 induced by thapsigargin. The transcription factor Elk1 is activated during thapsigargin-induced pip92 expression. Taken together, these results suggest that an increase of intracellular calcium ion levels by thapsigargin stimulates the pip92 expression via Raf-MEK-extracellular signal-regulated protein kinase- as well as Src kinase-dependent signaling pathways.

Finger replantation in the United States: rates and resource use from the 1996 Healthcare Cost and Utilization Project

Although finger replantation has been performed by hand surgeons in the United States for over 30 years the epidemiology of this procedure has not been studied. We used a national sampling database from the Agency for Health Care Policy and Research to summarize descriptive statistics surrounding finger replantation in the United States. This sample contained 304 cases of finger replantation performed in 1996. Mean hospital length of stay was 5.5 days and mean total charges were $20,330. Of the 906 hospitals included in this database, only 136 performed finger replantation during 1996. Of those, 60% performed only one case and 2% performed 10 or more cases. This descriptive analysis provides an examination of the largest sample size to date of finger replantation in the United States. Epidemiologic studies using national databases can provide researchers and policy makers with the analyses needed to examine treatment options and appropriately allocate future health care resources.

Lymphangiosarcoma (Stewart-Treves syndrome) in postmastectomy patients

Stewart-Treves syndrome (STS) is a rare but aggressive upper extremity lymphangiosarcoma in postmastectomy patients. Unfamiliarity with this disease and the innocuous appearance of the tumor often lead to delayed diagnosis. A comprehensive search of the databases at a single tertiary-care academic institution revealed only 3 cases of STS in the last 63 years. The latency time between breast cancer treatment and diagnosis of STS was 11 to 21 years. Survival after diagnosis of STS ranged from 8 to 15 months. One patient underwent radical surgery. The extensive lymphangiosarcoma in the other 2 patients precluded surgical resection and they underwent chemotherapy. All patients had adjuvant radiation therapy at the time of the original breast cancer resection. This report includes a discussion of the epidemiology, etiology, presentation, treatment, and prognosis of STS.

Cosmetic surgery and the internal morality of medicine

Cosmetic surgery is a fast-growing medical practice. In 1997 surgeons in the United States performed the four most common cosmetic procedures—liposuction, breast augmentation, eyelid surgery, and facelift—443,728 times, an increase of 150% over the comparable total for 1992. Estimated total expenditures for cosmetic surgery range from $1 to $2 billion. As managed care cuts into physicians' income and autonomy, cosmetic surgery, which is not covered by health insurance, offers a financially attractive medical specialty.

Expression of immediate early gene pip92 during anisomycin-induced cell death is mediated by the JNK- and p38-dependent activation of Elk1

We report here that immediate early gene pip92 is expressed during anisomycin-induced cell death in fibroblast NIH3T3 cells. To determine the mechanism by which this occurs and to identify downstream signaling pathways, we investigated the induction of the pip92 promoter. The activation of pip92 by anisomycin is mediated by the activation of MAP kinases, such as JNK and p38 kinase, but not ERK. Deletion analysis of the pip92 promoter indicated that pip92 activation occurs primarily within the region containing a serum response element (SRE). Further analysis of the SRE using a heterologous thymidine kinase promoter showed that both an Ets and CArG-like site are required for anisomycin-induced pip92 expression. Elk1, which binds to the Ets site, was phosphorylated by the JNK- and p38-dependent pathways and the phosphorylation of Elk1-GAL4 fusion proteins by these pathways was sufficient for the transactivation. Overall, this study suggested that different MAPK pathways are involved in the expression of immediate early gene pip92 by growth factors and environmental stresses.

A systemic administration of NMDA induces immediate early gene pip92 in the hippocampus

In the mammalian CNS, aspartate and glutamate are major excitatory amino acids, and their receptors are believed to mediate a wide range of physiological and pathological processes, including neurotransmission, plasticity, excitotoxicity, and various forms of neurodegeneration. The immediate early gene pip92 has been identified in serum-stimulated BALB/c 3T3 fibroblasts, activated T lymphocytes treated with cycloheximide, and fibroblast growth factor-stimulated hippocampal cells during neuronal differentiation. In this study we have demonstrated that pip92 is expressed in the mouse brain after a single intraperitoneal injection of NMDA. The distribution of pip92 mRNA levels in the NMDA-treated mouse brain was investigated using in situ RT-PCR. The region-specific activation of pip92 in the CNS was observed 3 h after NMDA injection, and high levels of pip92 mRNA were detected in the hippocampal dentate gyrus and piriform cortex regions. In addition, the activation of pip92 by NMDA was mediated by activation of mitogen-activated protein kinases (MAPKs), such as c-Jun N-terminal kinase (JNK) and p38 kinase, but not extracellular signal-regulated kinase (ERK) in the mouse hippocampus and immortalized rat hippocampal progenitor cells. This study suggests that pip92 is likely to play an important role in neuronal cell death induced by excitotoxic NMDA injury in the CNS.

An outcome study of thumb reconstruction using microvascular toe transfer

The purpose of this study was to evaluate outcomes following microvascular toe to thumb transfer in a cohort study using the Michigan Hand Outcomes Questionnaire, the 36-item Short-Form Health Survey, the Lower Limb Function Questionnaire, and standardized hand function tests. Twenty-one patients who had unilateral, isolated thumb amputations at the metacarpophalangeal joints were studied: 16 patients had toe transfer and 5 patients did not have reconstruction. The mean follow-up period was 7.2 years (range, 3-13 years). Toe transfer patients showed statistically significantly better overall hand function (effect size = 1.4), ADL (effect size = 3.4), work performance (effect size = 2.1), aesthetics (effect size = 1.9), and satisfaction (effect size = 1.1). Functional testing showed that strength and dexterity of the toe transfer hands were comparable to the opposite normal hands. Foot donor site morbidity was minimal. No significant difference was found in the mean Lower Limb Function Questionnaire scores between the toe transfer patients (1.4) and the amputation patients who did not undergo reconstruction (1.6). The results of our study showed that patients with toe transfer have better hand function than patients with thumb amputations at the level of the metacarpophalangeal joints.

Patient outcomes following Swanson silastic metacarpophalangeal joint arthroplasty in the rheumatoid hand: a systematic overview

OBJECTIVE

To investigate the effectiveness of Swanson silastic metacarpophalangeal joint arthroplasty (SMPA) in improving hand function for patients with rheumatoid arthritis.

METHODS

A systematic overview of all published series in the literature on SMPA from 1966 to 1999.

RESULTS

Research design deficiencies were quite prevalent in the literature on SMPA. However, SMPA was effective in correcting ulnar drift and in improving the arc of motion of the fingers. Health related quality of life was improved in the domains of hand function, pain, activities of daily living, aesthetics, and satisfaction.

CONCLUSION

SMPA appeared to be an effective procedure in correcting rheumatoid hand deformities. Future research must establish objective, quantifiable measures of hand function improvement by using standardized hand function tests and validated hand outcome questionnaires.

Reliability of physical examination of the upper extremity among keyboard operators

BACKGROUND

Physical examination is a traditional outcome measure in epidemiological research. Its value as a reliable measure depends, in part, on the prevalence of positive findings. The purpose of this paper is to determine the empirical reliability of physical examination and anthropometry in a field study of upper extremity disorders among keyboard operators.

METHODS

Two experienced examiners independently performed common provocative tests and procedures in physical examinations of the neck and upper extremity among 160 keyboard operators. Two additional examiners conducted anthropometric surveys among 137 workers. Inter-examiner reliability was assessed with observed agreement, kappa statistics, and intra-class correlations (ICC).

RESULTS

Observed agreement was between 96% and 100% for neck and upper extremity signs, muscle stretch reflexes, and muscle strength, however, with the exception of provocative tests, reliability statistics were unstable. Among the provocative tests, Phalen and Tinel tests had modest agreement after adjusting for chance (kappa range: 0.20-0.43). The carpal compression test had the best reliability (kappa=0.60 and kappa=0.67, left and right side, respectively). The ICCs for anthropometry ranged from 0.36-0.91.

CONCLUSIONS

Results from the study showed that statistically, except for the carpal compression test, physical examination contributed minimal reliable information. This was attributed mainly to the low prevalence of positive findings, and generally mild nature of upper extremity disorders in this population. The results are the best estimate of what would be found in a field study with experienced examiners. While it may reduce bias, separating physical examination from medical history may contribute to the poor reliability of findings. With a shift toward reliable measures, resources can be allocated to more effective tools, like questionnaires, in epidemiological research of upper extremity disorders among keyboard operators.

Maternal cigarette smoking during pregnancy and the risk of having a child with cleft lip/palate

Maternal cigarette smoking during pregnancy as a risk factor for having a child with cleft lip/palate has been suggested by several epidemiologic studies. However, most of these studies contained small sample sizes, and a clear association between these two factors could not be established. The U.S. Natality database from 1996 and a case-control study design were used to investigate the association between maternal smoking during pregnancy and having a child with cleft lip/palate. The records of 3,891,494 live births from the 1996 U.S. Natality database were extracted to obtain cleft lip/palate cases and random controls. The National Center for Health Statistics collects maternal and newborn demographic and medical data from the birth certificates of all 50 states. New York (excluding New York City), California, Indiana, and South Dakota did not collect smoking data, and the data from these states were excluded from the analysis. A total of 2207 live births with cleft lip/palate cases were identified, and 4414 controls (1:2 ratio) were randomly selected (using the SAS program) from live births with no congenital defects. Odds ratios and 95 percent confidence intervals were determined from logistic regression models, adjusting for confounding variables, including maternal demographic and medical risk factors. A significant association was found between any amount of maternal cigarette use during pregnancy and having a child with cleft lip/palate [unadjusted odds ratio 1.55 (1.36, 1.76), p < 0.001]. Univariate analysis showed that maternal education level, age, race, and maternal medical conditions (diabetes and pregnancy-associated hypertension) were potential confounders. After adjusting for these confounders, the odds ratio remained significant [Mantel-Haenszel odds ratio 1.34 (1.16, 1.54), p < 0.001]. To determine the dose response of cigarette smoking during pregnancy, the cigarette consumption per day was divided into four groups: none, 1 to 10, 11 to 20, and 21 or more. A dose-response relationship was found when comparing each smoking category with the no smoking reference group: 1.50 (1.28, 1.76), 1.55 (1.23, 1.95), and 1.78 (1.22, 2.59), respectively. This means that increased cigarette smoking during pregnancy resulted in increased odds of having a child with cleft lip/palate. This is the largest study to date to test the association between maternal cigarette smoking during pregnancy and having a newborn with cleft lip/palate. The significant trend in the dose-response relationship strongly suggests the association of smoking tobacco and this common congenital deformity. These results emphasize the public health risks associated with smoking during pregnancy. To prevent this devastating craniofacial anomaly, educational initiatives should be considered that will alert expectant mothers to the association between smoking during pregnancy and the occurrence of cleft lip/palate.