GripAble: Interrater reliability and normative grip strength of UK population

BACKGROUND

Hand grip strength is an established indicator of individual health status and is used as a biomarker for predicting mortality, disability, and disease risks. GripAble hand grip dynamometer offers a modernized approach to measuring grip strength with its digital and high-accuracy measurement system.

PURPOSE

This study aimed to (1) assess the interrater reliability of maximum grip strength (MGS) measurement and (2) establish GripAble's own gender-, age group- and hand-stratified normative MGS reference values of the adult UK population.

STUDY DESIGN

Cross-sectional study design.

METHODS

Interrater reliability among three raters assessing 30 participants across diverse age groups was measured using the intraclass correlation. In the second study, 11 investigators gathered MGS data from 907 participants across diverse age groups and gender. The average, standard deviation, minimum, median, maximum, and percentiles of MGS were computed for each gender, age group, and hand (L/R). The relationship between MGS and age was examined using quantile regression analysis. Additionally, generalized linear model regression analysis was conducted to explore the influence of participants' demographics (gender, hand [L/R], hand length, hand circumference, age, weight, and height) on MGS.

RESULTS

MGS measurements between raters showed excellent agreement (ICC(2,1) = 0.991, 95% confidence interval [0.98, 1.0]). The MGS and age relationship follows a curvilinear pattern, reaching a peak median MGS values of up to 20 kg between 30 and 49 years for females and up to 35 kg between 30 and 59 years for males. Subsequently, MGS declined as age advanced. Gender and hand (L/R) emerged as the primary factors influencing MGS, followed by hand length, hand circumference, age, weight, and height.

CONCLUSIONS

The presented normative MGS reference values can be used for interpreting MGS measurements obtained from adults in the United Kingdom using GripAble. This study, along with previous studies on GripAble devices, confirms GripAble as a reliable and valid tool for measuring MGS.

GripAble: An accurate, sensitive and robust digital device for measuring grip strength

Introduction

Grip strength is a reliable biomarker of overall health and physiological well-being. It is widely used in clinical practice as an outcome measure. This paper demonstrates the measurement characteristics of GripAble, a wireless mobile handgrip device that measures grip force both isometrically and elastically-resisted for assessment and training of hand function.

Methods

A series of bench tests were performed to evaluate GripAble's grip force measurement accuracy and sensitivity. Measurement robustness was evaluated through repeated drop tests interwoven with error verification test phases.

Results

GripAble's absolute measurement error at the central position was under 0.81 and 1.67 kg (95^th percentiles; N = 47) when measuring elastically and isometrically, respectively, providing similar or better accuracy than the industry-standard Jamar device. Sensitivity was measured as 0.062 ± 0.015 kg (mean ± std; 95^th percentiles: [0.036, 0.089] kg; N = 47), independent of the applied force. There was no significant performance degradation following impact from 30 drops from a height >1.5 m.

Conclusion

GripAble is an accurate and reliable grip strength dynamometer. It is highly sensitive and robust, which in combination with other novel features (e.g. portability, telerehabilitation and digital data tracking) enable broad applicability in a range of clinical caseloads and environments.

Modernising grip dynamometry: Inter-instrument reliability between GripAble and Jamar

INTRODUCTION

Maximum grip strength (MGS) is a reliable biomarker of overall health and physiological well-being. Therefore, an accurate and reliable measurement device is vital for ensuring the validity of the MGS assessment. This paper presents GripAble, a mobile hand grip device for the assessment of MGS. GripAble's performance was evaluated using an inter-instrument reliability test against the widely used Jamar PLUS+ dynamometer.

METHODS

MGS data from sixty-three participants (N = 63, median (IQR) age = 29.0 (29.5) years, 33 M/30 F) from both hands using GripAble and Jamar PLUS+ were collected and compared. Intraclass correlation (ICC), regression, and Bland and Altman analysis were performed to evaluate the inter-instrument reliability and relationship in MGS measurements between GripAble and Jamar PLUS+ .

RESULTS

GripAble demonstrates good-to-excellent inter-instrument reliability to the Jamar PLUS+ with ICC3,1 = 0.906 (95% CI [0.87-0.94]). GripAble's MGS measurement is equivalent to 69% (95% CI [0.67-0.71]%) of Jamar PLUS+'s measurement. There is a proportional difference in mean MGS between the two devices, with the difference in MGS between GripAble and Jamar PLUS+ increasing with MGS.

CONCLUSION

The GripAble is a reliable tool for measuring grip strength. However, the MGS readings from GripAble and Jamar PLUS+ should not be interchanged for serial measurements of the same patient, nor be translated directly from one device to the other. A new normative MGS data using GripAble will be collected and accessed through the software for immediate comparison to age and gender-matched subpopulations.

Facultative Parthenogenesis in California Condors

Parthenogenesis is a relatively rare event in birds, documented in unfertilized eggs from columbid, galliform, and passerine females with no access to males. In the critically endangered California condor, parentage analysis conducted utilizing polymorphic microsatellite loci has identified two instances of parthenogenetic development from the eggs of two females in the captive breeding program, each continuously housed with a reproductively capable male with whom they had produced offspring. Paternal genetic contribution to the two chicks was excluded. Both parthenotes possessed the expected male ZZ sex chromosomes and were homozygous for all evaluated markers inherited from their dams. These findings represent the first molecular marker-based identification of facultative parthenogenesis in an avian species, notably of females in regular contact with fertile males, and add to the phylogenetic breadth of vertebrate taxa documented to have reproduced via asexual reproduction.

Influence of visual-coupling on bimanual coordination in unilateral spastic cerebral palsy

Controlling two objects simultaneously during a bimanual task is a cognitively demanding process; both hands need to be temporally and spatially coordinated to achieve the shared task goal. Children with unilateral spastic cerebral palsy (USCP) exhibit severe sensory and motor impairments to one side of their body that make the process of coordinating bimanual movements particularly exhausting. Prior studies have shown that performing visually-coupled task could reduce cognitive interference associated with performing 'two tasks at once' in an uncoupled bimanual task. For children with USCP, who also present with cognitive delay, performing this type of task may allow them to process and plan their movement faster. We tested this hypothesis by examining the grip force control of 7 children with USCP during unimanual and visually-coupled bimanual tasks. Results demonstrated that despite the visual coupling, the bimanual coordination of these children remained impaired. However, there may be a potential benefit of visually-coupled task in encouraging both hands to initiate in concert. The implication of the study for children with USCP is discussed.

Augmented manipulation ability in humans with six-fingered hands

Neurotechnology attempts to develop supernumerary limbs, but can the human brain deal with the complexity to control an extra limb and yield advantages from it? Here, we analyzed the neuromechanics and manipulation abilities of two polydactyly subjects who each possess six fingers on their hands. Anatomical MRI of the supernumerary finger (SF) revealed that it is actuated by extra muscles and nerves, and fMRI identified a distinct cortical representation of the SF. In both subjects, the SF was able to move independently from the other fingers. Polydactyly subjects were able to coordinate the SF with their other fingers for more complex movements than five fingered subjects, and so carry out with only one hand tasks normally requiring two hands. These results demonstrate that a body with significantly more degrees-of-freedom can be controlled by the human nervous system without causing motor deficits or impairments and can instead provide superior manipulation abilities.

Bimanual coordination during a physically coupled task in unilateral spastic cerebral palsy children

Background

Single object bimanual manipulation, or physically-coupled bimanual tasks, are ubiquitous in daily lives. However, the predominant focus of previous studies has been on uncoupled bimanual actions, where the two hands act independently to manipulate two disconnected objects. In this paper, we explore interlimb coordination among children with unilateral spastic cerebral palsy (USCP), by investigating upper limb motor control during a single object bimanual lifting task.

Methods

15 children with USCP and 17 typically developing (TD) children performed a simple single-object bimanual lifting task. The object was an instrumented cube that can record the contact force on each of its faces alongside estimating its trajectory during a prescribed two-handed lifting motion. The subject’s performance was measured in terms of the duration of individual phases, linearity and monotonicity of the grasp-to-load force synergy, interlimb force asymmetry, and movement smoothness.

Results

Similar to their TD counterparts, USCP subjects were able to produce a linear grasp-to-load force synergy. However, they demonstrated difficulties in producing monotonic forces and generating smooth movements. No impairment of anticipatory control was observed within the USCP subjects. However, our analysis showed that the USCP subjects shifted the weight of the cube onto their more-abled side, potentially to minimise the load on the impaired side, which suggests a developed strategy of compensating for inter-limb asymmetries, such as muscle strength.

Conclusion

Bimanual interaction with a single mutual object has the potential to facilitate anticipation and sequencing of force control in USCP children unlike previous studies which showed deficits during uncoupled bimanual actions. We suggest that this difference could be partly due to the provision of adequate cutaneous and kinaesthetic information gathered from the dynamic exchange of forces between the two hands, mediated through the physical coupling.

Balancing the playing field: collaborative gaming for physical training

Background

Multiplayer video games promoting exercise-based rehabilitation may facilitate motor learning, by increasing motivation through social interaction. However, a major design challenge is to enable meaningful inter-subject interaction, whilst allowing for significant skill differences between players. We present a novel motor-training paradigm that allows real-time collaboration and performance enhancement, across a wide range of inter-subject skill mismatches, including disabled vs. able-bodied partnerships.

Methods

A virtual task consisting of a dynamic ball on a beam, is controlled at each end using independent digital force-sensing handgrips. Interaction is mediated through simulated physical coupling and locally-redundant control. Game performance was measured in 16 healthy-healthy and 16 patient-expert dyads, where patients were hemiparetic stroke survivors using their impaired arm. Dual-player was compared to single-player performance, in terms of score, target tracking, stability, effort and smoothness; and questionnaires probing user-experience and engagement.

Results

Performance of less-able subjects (as ranked from single-player ability) was enhanced by dual-player mode, by an amount proportionate to the partnership’s mismatch. The more abled partners’ performances decreased by a similar amount. Such zero-sum interactions were observed for both healthy-healthy and patient-expert interactions. Dual-player was preferred by the majority of players independent of baseline ability and subject group; healthy subjects also felt more challenged, and patients more skilled.

Conclusion

This is the first demonstration of implicit skill balancing in a truly collaborative virtual training task leading to heightened engagement, across both healthy subjects and stroke patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12984-017-0319-x) contains supplementary material, which is available to authorized users.

Validity of a sensor-based table-top platform to measure upper limb function

Objective measurement is an essential part of the assessment process in neurological dysfunction such as stroke. However, current clinical scores are insensitive and based on subjective observation from experts. Technology provides an opportunity for enhanced accuracy and specificity of objective measurement. This study describes the use of an interactive force-sensitive table-top platform for the assessment of reach in post-stroke patients, admitted as part of a three week intensive upper limb training programme. Objective measures from the reachable workspace were extracted and included normalised reach distance, normalised reached speed and reach dragging. The data was compared to standardised Fugl-Meyer (FM) clinical scores, recorded at admission (FMPRE) and discharge (FMPOST). Results indicate strong relationships between the three objective measures and subjective FM scores, with significant Spearman correlations found in all cases (|ρ| > 0.5, p < 0.05). The results highlight the validity for a sensor-based table-top system to provide a simple, flexible, and objective platform for assessment of impaired upper limb motor function.

Universal Self-Similar Scaling of Spatial Wilson Loops Out of Equilibrium

We investigate strongly correlated non-Abelian plasmas out of equilibrium. Based on numerical simulations, we establish a self-similar scaling property for the time evolution of spatial Wilson loops that characterizes a universal state of matter far from equilibrium. Most remarkably, it exhibits a generalized area law which holds for a sufficiently large ratio of spatial area and fractional power of time. Performing calculations also for the perturbative regime at higher momenta, we are able to characterize the full nonthermal scaling properties of SU(2) and SU(3) symmetric plasmas from short to large distance scales in terms of two independent universal exponents and associated scaling functions.

Elasticity improves handgrip performance and user experience during visuomotor control

Passive rehabilitation devices, providing motivation and feedback, potentially offer an automated and low-cost therapy method, and can be used as simple human-machine interfaces. Here, we ask whether there is any advantage for a hand-training device to be elastic, as opposed to rigid, in terms of performance and preference. To address this question, we have developed a highly sensitive and portable digital handgrip, promoting independent and repetitive rehabilitation of grasp function based around a novel elastic force and position sensing structure. A usability study was performed on 66 healthy subjects to assess the effect of elastic versus rigid handgrip control during various visuomotor tracking tasks. The results indicate that, for tasks relying either on feedforward or on feedback control, novice users perform significantly better with the elastic handgrip, compared with the rigid equivalent (11% relative improvement, 9-14% mean range; p < 0.01). Furthermore, there was a threefold increase in the number of subjects who preferred elastic compared with rigid handgrip interaction. Our results suggest that device compliance is an important design consideration for grip training devices.

A Network Model of Local Field Potential Activity in Essential Tremor and the Impact of Deep Brain Stimulation

Essential tremor (ET), a movement disorder characterised by an uncontrollable shaking of the affected body part, is often professed to be the most common movement disorder, affecting up to one percent of adults over 40 years of age. The precise cause of ET is unknown, however pathological oscillations of a network of a number of brain regions are implicated in leading to the disorder. Deep brain stimulation (DBS) is a clinical therapy used to alleviate the symptoms of a number of movement disorders. DBS involves the surgical implantation of electrodes into specific nuclei in the brain. For ET the targeted region is the ventralis intermedius (Vim) nucleus of the thalamus. Though DBS is effective for treating ET, the mechanism through which the therapeutic effect is obtained is not understood. To elucidate the mechanism underlying the pathological network activity and the effect of DBS on such activity, we take a computational modelling approach combined with electrophysiological data. The pathological brain activity was recorded intra-operatively via implanted DBS electrodes, whilst simultaneously recording muscle activity of the affected limbs. We modelled the network hypothesised to underlie ET using the Wilson-Cowan approach. The modelled network exhibited oscillatory behaviour within the tremor frequency range, as did our electrophysiological data. By applying a DBS-like input we suppressed these oscillations. This study shows that the dynamics of the ET network support oscillations at the tremor frequency and the application of a DBS-like input disrupts this activity, which could be one mechanism underlying the therapeutic benefit.

Essential tremor (ET) is acknowledged to be the most common movement disorder affecting 1% of the population. Although the underlying mechanisms remain elusive, the thalamus, cortex and cerebellum are implicated in the underlying pathology. More recently, it has been shown that ET can be successfully treated by deep brain stimulation (DBS). This clinical treatment involves the surgical implantation of electrodes into the brain, through which current is applied. However, the mechanisms of how DBS achieves clinical benefit continue to be debated. A key question is whether ET can be modeled as a pathological network behavior as has been suggested previously. If so, we can then ask how DBS would modulate this brain activity. Our study combines: (i) simultaneous electrophysiological recordings from the brain and muscle; (ii) computational modelling; (iii) mathematical analysis. We found that the network supports oscillations in the tremor range, and the application of high frequency DBS switches this to low amplitude, high-frequency activity. We propose that our model can be used to predict DBS parameter settings that suppress pathological network activity and consequently tremor. In summary, we provide the first population level model of essential tremor including the effect of DBS on network behaviour.

SITAR: a system for independent task-oriented assessment and rehabilitation

INTRODUCTION

Over recent years, task-oriented training has emerged as a dominant approach in neurorehabilitation. This article presents a novel, sensor-based system for independent task-oriented assessment and rehabilitation (SITAR) of the upper limb.

METHODS

The SITAR is an ecosystem of interactive devices including a touch and force-sensitive tabletop and a set of intelligent objects enabling functional interaction. In contrast to most existing sensor-based systems, SITAR provides natural training of visuomotor coordination through collocated visual and haptic workspaces alongside multimodal feedback, facilitating learning and its transfer to real tasks. We illustrate the possibilities offered by the SITAR for sensorimotor assessment and therapy through pilot assessment and usability studies.

RESULTS

The pilot data from the assessment study demonstrates how the system can be used to assess different aspects of upper limb reaching, pick-and-place and sensory tactile resolution tasks. The pilot usability study indicates that patients are able to train arm-reaching movements independently using the SITAR with minimal involvement of the therapist and that they were motivated to pursue the SITAR-based therapy.

CONCLUSION

SITAR is a versatile, non-robotic tool that can be used to implement a range of therapeutic exercises and assessments for different types of patients, which is particularly well-suited for task-oriented training.

Democratizing Neurorehabilitation: How Accessible are Low-Cost Mobile-Gaming Technologies for Self-Rehabilitation of Arm Disability in Stroke?

Motor-training software on tablets or smartphones (Apps) offer a low-cost, widely-available solution to supplement arm physiotherapy after stroke. We assessed the proportions of hemiplegic stroke patients who, with their plegic hand, could meaningfully engage with mobile-gaming devices using a range of standard control-methods, as well as by using a novel wireless grip-controller, adapted for neurodisability. We screened all newly-diagnosed hemiplegic stroke patients presenting to a stroke centre over 6 months. Subjects were compared on their ability to control a tablet or smartphone cursor using: finger-swipe, tap, joystick, screen-tilt, and an adapted handgrip. Cursor control was graded as: no movement (0); less than full-range movement (1); full-range movement (2); directed movement (3). In total, we screened 345 patients, of which 87 satisfied recruitment criteria and completed testing. The commonest reason for exclusion was cognitive impairment. Using conventional controls, the proportion of patients able to direct cursor movement was 38–48%; and to move it full-range was 55–67% (controller comparison: p>0.1). By comparison, handgrip enabled directed control in 75%, and full-range movement in 93% (controller comparison: p<0.001). This difference between controllers was most apparent amongst severely-disabled subjects, with 0% achieving directed or full-range control with conventional controls, compared to 58% and 83% achieving these two levels of movement, respectively, with handgrip. In conclusion, hand, or arm, training Apps played on conventional mobile devices are likely to be accessible only to mildly-disabled stroke patients. Technological adaptations such as grip-control can enable more severely affected subjects to engage with self-training software.

Blinatumomab for the treatment of adult acute lymphoblastic leukemia

The marker CD19 is frequently expressed on the surface of malignant B cells including non-Hodgkin's lymphoma (NHL), chronic lymphocytic leukemia (CLL) and acute lymphoblastic leukemia (ALL), which makes it an attractive target for antineoplastic therapy (1). T cells are part of the immune surveillance system for malignant cells (2). Blinatumomab is a bispecific T cell engager (BiTE(®)) antibody that binds both CD3-positive T cells and CD19-positive B cells via its two variable antigen-binding domains. Once bound to both the T and B cell, blinatumomab induces T-cell activation and subsequently perforin-mediated malignant B-cell death. It has shown efficacy in ALL with minimal residual disease, relapsed/refractory ALL, and NHL in phase I and II clinical trials. With a favorable safely profile and promising results, blinatumomab was granted accelerated FDA approval to treat B-cell ALL in December 2014. Herein, we will review the most relevant data related to blinatumomab in ALL.

Ensemble classification for robust discrimination of multi-channel, multi-class tongue-movement ear pressure signals

In this paper we introduce a robust classification framework for tongue-movement ear pressure signals based around an ensemble voting methodology. The ensemble members are comprised of different combinations of sensor inputs i.e. two in-ear microphones and an acoustic gel sensor positioned under the chin of the individual and classification using three different base models. It is shown that by using all nine ensemble members when compared to the individual (base) models, the average misclassification rate can be reduced from 23% to 2.8% when using the majority voting strategy. The correct classification rate is improved from 76% to 92.4% when utilizing either the borda count or condorcet methods. This is achieved through a combination of rejection based on ambiguity in the ensemble and diversity in the misclassified instances across the ensemble members.

Metastatic breast cancer detection and therapy monitoring using folate-targeting flow cytometry

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Background: Circulating tumor cell (CTC) has emerged as a valuable surrogate tumor marker for cancer diagnosis, prognosis, therapy personalization, and drug discovery. To identify CTCs, EpCAM and/or cytokeratin have been commonly used; however, their expression may diminish for subgroups of breast cancers or during epithelial-mesenchymal transition. A unique approach by targeting folate receptor (FR) on CTCs overcomes the limitation. Cancer cells overexpress FR with high affinity (KD=0.1 nM) to internalize high levels of folate for rapid growth. FR is also found upregulated in most cancers, while at very low levels in normal tissues.

Methods: A flow cytometry based in-vitro CTC assay kit (OncoIVDx) was developed by IV Diagnostics Inc to specifically enumerate CTCs which overexpress FRs. 20 mL of 9 metastatic breast cancer (MBC) patients' peripheral blood was collected using CellSave tube before and after the treatment in midst of therapy. CTCs were tagged by fluorescently labeled folate conjugate, while leukocytes were counterstained by anti-CD45. To absolutely count the rare CTCs, a fluorescent bead was added serving internal control.

Results: Table.

Conclusions: No obvious shift in dot plots was found for patients' leucocytes compared to those in normal sample. Tumor size, histologic grade, nodal involvement and lymphovascular invasion (LVI) did not display a significant association with CTC presence, although more positive nodes with identified LVI might indicate an unfavorable increase in CTC counts. CTC presence was found associated with serum marker CA27.29. A score of 30 and less correlated with CTC response to the treatment. Chemotherapy alone or in combination with hormone therapy did not correlate with the change in CTC counts after treatment, except for hormone therapy alone. Unfavorable progression of cancers could be predicated for the patients with approximately 25 and more CTCs. We would like to thank NIH/NCI for SBIR phase I grant (1R43CA13789301A1).

[Table: see text]

Outbreak of haemolytic uraemic syndrome and bloody diarrhoea due to Escherichia coli O104:H4, south-west France, June 2011

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Molecular epidemiology of Mycobacterium avium subsp. avium and Mycobacterium intracellulare in captive birds

Mycobacterium avium subsp. avium and Mycobacterium intracellulare are primary causes of mycobacteriosis in captive birds throughout the world, but little is known about how they are transmitted. To define the local epidemiology of infection, we strain-typed 70 M. avium subsp. avium and 15 M. intracellulare culture isolates obtained over a 4-year period from captive birds. Typing was performed using randomly amplified polymorphic DNA (RAPD) PCR, amplified fragment length polymorphic (AFLP) fragment analyses, and for a subset of isolates, DNA sequencing of a segment of the 16S-23S rRNA internal transcribed spacer region. Six strain clusters comprising 43 M. avium subsp. avium, isolates were identified; 42 isolates had unique typing patterns, including all M. intracellulare isolates. Phylo-geographical analyses using RAPD and AFLP fingerprints and animal confinement histories showed no correlation between housing of infected birds and mycobacterial strain-type, except for two animals. The diversity of M. avium subsp. avium and M. intracellulare isolates and minimal evidence for bird-to-bird transmission suggest that environmental reservoirs may be important sources of infection in captivity.

Protein cross-migration during isolation of nuclei from mixtures of heated and unheated HeLa cells

To investigate the cross-migration of proteins during nuclear isolation heated and control cells were mixed prior to nuclear isolation. These nuclei were stained with fluorescein isothiocyanate (FITC, a protein-specific stain) and with propidium iodide (PI, a DNA-specific stain). Flow cytometric (FCM) analysis showed two populations distinguishable on the basis of protein content. The protein content of the nuclei in the upper population was identical to that for nuclei isolated from heated cells while that for the lower population had a protein content identical to the protein content of nuclei from control cells. This result shows that the heat-induced increase in nuclear protein content occurred throughout the entire population of nuclei (i.e., in G1, S, and G2 nuclei) and that the measured protein content of nuclei was not affected by the presence of the other population during isolation. The capability of the FCM to sort subpopulations from different regions of a histogram was used to separate the subpopulations after analysis. When control cells were prelabeled with [3H]leucine and mixed with unlabeled heated cells, 11% of the radioactivity was found to be associated with the nuclei from heated cells. Autoradiographs showed grains over approximately 99% of the nuclei from heated cells. When [3H]TdR was used as a label in a similar experiment, only 0-3% of the label was observed to become associated with the population of nuclei from heated cells and autoradiography showed that 97% of these nuclei were not labeled. Comparable results were obtained when the labeled cells were heated and the control cells were left unlabeled. These results show that a small amount of protein (approximately 10% of the nuclear protein) will cross-migrate during nuclear isolation without affecting the net amount of protein in either population.

Characterization of complementary deoxyribonucleic acid and genomic deoxyribonucleic acid for the beta chain of human fibrinogen

A total of 148 cDNAs coding for the beta chain of human fibrinogen have been identified from a human liver cDNA library employing a bovine cDNA as a probe. The largest cDNA insert contained 1932 base pairs cloned into the PstI site of plasmid pBR322. This cDNA insert contained 66 base pairs coding for a portion or all of a signal sequence, 1383 base pairs coding for 461 amino acids in the mature protein, a stop codon of TAG, a noncoding region of 431 base pairs, and a poly(A) tail of 19 base pairs. Most of the cDNA inserts coding for the beta chain were found to have a noncoding region of 98 or 167 base pairs rather than 431 base pairs at the 3'-end. The bovine cDNA for the beta chain was also employed as a probe for screening a lambda phage library containing human genomic DNA. Seven positive phage were identified. One of the phage, which contained the entire gene for the beta chain of fibrinogen, was examined by electron microscopy, and portions of its DNA sequence are presented. Seven intervening sequences were identified in the gene for the beta chain of human fibrinogen. The largest intervening sequence (approximately 1.3 kilobases) was found at the 5'-end of the gene and was located between amino acid residues 8 and 9, which are present in fibrinopeptide B. A sequence analysis of the 5'-end of the gene also indicated that the B chain of human fibrinogen contained a signal sequence of either 16, 27, or 30 amino acid residues.

Dimethyl sulfoxide alteration of collagen

In vitro incubation of human scar in our laboratory with 99% DMSO demonstrated, by electron microscopy, the disruption of the collagen fibers. This may prove to be a useful preparatory step for selective enzymatic assault upon exuberant or undesirable scar tissue in the clinical setting. Further study of this concept is planned.

Sequence homology and structural comparison between the chromosomal human alpha 1-antitrypsin and chicken ovalbumin genes

The human chromosomal alpha 1-antitrypsin gene has been cloned. This gene is approximately 5 kilobase pairs long and contains three intervening sequences in the peptide-coding region. DNA sequences coding for the amino and carboxyl termini of a alpha 1-antitrypsin have been identified. Human alpha 1-antitrypsin and chicken ovalbumin show significant sequences homology and belong to a common protein super-family. Yet the number, position and size of intervening sequences reveal that the two genes are dissimilar.

Mosaic structure and mRNA precursors of uteroglobin, a hormone-regulated mammalian gene

The synthesis of uteroglobin in the rabbit uterus is induced by progesterone and is repressed by estrogen which has an over-riding effect over the inducer. The dual hormonal control system offers an excellent model for studying hormonal regulation of mammalian gene expression. Using a full-length uteroglobin cDNA clone as a specific hybridization probe, recombinant lambda phages containing the entire chromosomal uteroglobin gene have been isolated from a rabbit genomic DNA library. Electronmicroscopic analysis of hybrid molecules formed between the chromosomal uteroglobin gene and uteroglobin mRNA indicated the presence of 2 intervening sequences within this gene. The mosaic structure of the uteroglobin gene has been substantiated by detailed restriction mapping and Southern hybridization. The gene is 3.0 kilobases in length to code for a mature mRNA of 465 nucleotides. Northern hybridization of poly(A)-containing RNA from 4-day-pregnant rabbit uterus with the full-length cDNA clone revealed the presence of uteroglobin mRNA precursors. The size of the largest precursor RNA species detected by the cDNA clone is the same as the entire chromosomal uteroglobin gene. The fidelity of the precursor RNAs was established by their ability to hybridize with specific intervening sequence probes. Thus the entire uteroglobin gene is expressed into primary RNA transcripts, which are subsequently processed into mature mRNA molecules by splicing.

A suggestion of linkage between the Marfan syndrome and the rhesus blood group

The linkage relationships of the locus for the Marfan Syndrome were investigated with 19 marker loci in 17 families. Close linkage with several marker loci was excluded. There was a suggestion of linkage between the locus for the Marfan Syndrome and Rh.

Parkinson's disease

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Phagocytosis of asbestos fibers by human pulmonary alveolar macrophages

Human pulmonary alveolar macrophages (PAMs) were cultured for 24--72 h with varying concentrations (0--300 microgram/ml) of amosite asbestos (AS). At lower AS concentrations, (less than 100 microgram/ml) no decrease in cell viability occurred during the first 24 h of culture. Significant cytotoxicity (P less than 0.005 in all instances) was observed, however, following incubation for 24 h with higher AS concentrations (greater than 100 microgram/ml). Even following incubation with lower concentrations of AS, significant cytotoxicity (P less than 0.006 in all instances) was observed after 48 or 72 h of culture. Scanning electron microscopy (SEM) clearly illustrates the various stages of AS phagocytosis by PAMs. SEM also documented morphological changes in PAMs following AS exposure. These included increased zeiosis and the appearance of a fibrous-like material on the surface of AS fibers following initial contact with the PAM cytoplasmic membrane. Further study of the biological interactions between AS and human cells, such as PAMs, might provide valuable information regarding the etiology of AS-related lung disorders.

Autosomal dominantly inherited adductor laryngeal paralysis--a new syndrome with a suggestion of linkage to HLA

A family is reported with autosomal dominantly inherited congenital bilateral adductor paralysis of the larynx. This disorder has apparently not been described previously. A search for linkage in this family with the loci for 19 other genetic markers showed a suggestion of linkage with HLA and GLO, and accordingly a suggestion that the locus for this disorder may be assigned to chromosome 6.