When do tissues and cells become products? – Regulatory oversight of emerging biological therapies

Although therapeutics derived from biological sources have been subjected to regulatory oversight for some time, the products used in transplantation procedures have historically been exempt from this oversight. These products have been viewed as being part of medical practice rather than as the result of mainstream pharmaceutical manufacture. Furthermore, their unique source makes them difficult to assess in traditional regulatory systems based on the␣tenets of pharmaceutical quality control. With the␣increasing use of transplantation therapies to both replace dysfunctional organs and to influence genetic and metabolic processes, public health concerns on these therapies have increased. In addition, it is recognized that therapeutic claims for some of these interventions need to be properly assessed. These considerations have led the established regulatory agencies of the developed world to develop new regulatory paradigms for the products of transplantation practice. While a number of concerns have driven these developments, the minimization of infectious disease risk remains the paramount driver for introducing these regulatory systems. More than the regulation of medicines and medical devices manufactured in traditional pharmaceutical modes, the regulation of cell and tissue products is intimately linked to areas of public health policy and funding. This places regulators in a challenging position as they attempt to reconcile their roles as independent assessors with the needs of the overall public health framework. This is particularly difficult when considering measures which may affect access to life saving therapies. Regulators have recognized the need to assess these therapies through systems which incorporate consideration of risk-benefit ratios and include mechanisms for transparent and accountable release of products when full compliance to traditional concepts of manufacturing practice is not possible.     

Optimality of phylogenetic nomenclatural procedures

Nomenclatures resulting from the application of various procedures are viewed as communication tools whose optimality can be compared. The traditional, node-based, branch-based, apomorphy-based, and cladotypic procedures are compared based on theoretical cases. The traditional procedure collects several major drawbacks: endings related to ranks are of low information content on taxa hierarchy; with respect to procedures using uninominal species names, in case of a partly unbalanced and/or partly unresolved phylogeny, the application of the procedure results into supernumerary names; a traditional taxon name is prone to be polysemic, depending upon someone’s opinion on the rank and composition of the taxon, and upon conflicting hypotheses on the phylogenetic position of name-bearing types. Alternative systems vary in merit. Names of apomorphy-defined taxa are prone to be polysemic due to possible ambiguity in the formulation of the defining character state. The cladotypic nomenclatural procedure is similar in that respect, but a set of rules allow ambiguity to be limited. The main issue of node- and branch-based procedures is that cases of synonymy cannot be settled if the inner phylogeny of taxa cannot be resolved. Cases of irresolvable synonymy can occur under apomorphy-based and cladotypic procedures, but the problem can be circumvented by the use of taxa whose defining character state is not subject to ambiguous mapping. Node-, branch- and apomorphy-based definitions as governed by the PhyloCode can produce nonsensical statements, but this problem can be fixed by the adjunction of falsifiable assumptions in use under the cladotypic procedure. Cladotypic definitions must involve a fourth assumption formulated as ‘cladotypes belong to different species’ (cladogenesis assumption). The present contribution suggests that the cladotypic procedure outperforms all other proposed procedures, producing an optimal formal lexicon useful for naming and communicating about species and taxa.     

Should Deceased Donation be Morally Preferred in Uterine Transplantation Trials?

In recent years much research has been undertaken regarding the feasibility of the human uterine transplant (UTx) as a treatment for absolute uterine factor infertility (AUFI). Should it reach clinical application this procedure would allow such individuals what is often a much‐desired opportunity to become not only social mothers (via adoption or traditional surrogacy arrangements), or genetic and social mothers (through gestational surrogacy) but mothers in a social, genetic and gestational sense. Like many experimental transplantation procedures such as face, hand, corneal and larynx transplants, UTx as a therapeutic option falls firmly into the camp of the quality of life (QOL) transplant, undertaken with the aim, not to save a life, but to enrich one. However, unlike most of these novel procedures – where one would be unlikely to find a willing living donor or an ethics committee that would sanction such a donation – the organs to be transplanted in UTx are potentially available from both living and deceased donors. In this article, in the light of the recent nine‐case research trial in Sweden which used uteri obtained from living donors, and the assertions on the part of a number of other research teams currently preparing trials that they will only be using deceased donors, I explore the question of whether, in the case of UTx, there exist compelling moral reasons to prefer the use of deceased donors despite the benefits that may be associated with the use of organs obtained from the living.     

The water relations of Lithobius forficatus and the role of the coxal organs (Myriapoda: Chilopoda)

The water relations of the common brown centipede, Lithobius forficatus (L.), are examined with regard to the possible involvement of the coxal organs in water uptake. Centipedes with blocked and open coxal pores are subjected to a variety of dehydration and rehydration regimes and weight change over time measured. Weight loss and regain is related to body surface area and is not influenced by the coxal organs.
The conclusion of the paper is that the coxal organs of L. forficatus do not contribute significantly to the ability of these animals to recover water lost through cuticular transpiration.     

Large-scale purification of enzymes

Many standard procedures for the purification of proteins in the laboratory do not readily lend themselves to scaling up, whereas, on the other hand, some techniques relatively unsatisfactory in the laboratory are much more effective on a large scale. When producing gram or kilogram quantities of enzymes for use over an extended period, the storage properties and general tractability of the purified products become increasingly important. Hence enzymes from thermophilic sources frequently have advantages over those from mesophiles. The possible economic advantages of simultaneous large-scale multi-enzyme isolation over separate individual enzyme purifications are evaluated. Batchwise adsorption and elution from ion-exchange celluloses frequently replace traditional precipitation techniques in the early stages of a large-scale purification. Dialysis is replaced by concentration, dilution and reconcentration with the use of hollow-fibre ultrafiltration equipment. Antiphonally direct scaling-up of column chromatographic procedures is usually possible. Modifications to column geometry to maximize flow rates are often desirable but purification factors and recoveries comparable with those obtained on the laboratory scale can be achieved relatively easily. Classical affinity chromatographic techniques have not proved so amenable to large-scale work, mainly because of the enormous expense and rather short life of the matrices. However, the quasi-affinity chromatography afforded by the triazine dye conjugates has proved of great benefit. The materials are cheap to prepare. The coupling procedures are both simple and rapid and do not involve the use of noxious chemicals such as cyanogen bromide. Moreover the triazine linkage is more stable under a variety of conditions than the isourea formed in cyanogen bromide coupling. Considerable further exploitation of these versatile matrices is expected.     

A Re-Evaluation of the Place of Major Extirpation in the Management of Patients with Metastatic Mammary Carcinoma

Clearly defined indications for major extirpation procedures in metastatic mammary carcinoma are lacking. A reassessment of experience with 222 patients (133 after adrenalectomies and 89 after hypophysectomies) was therefore undertaken. This experience has changed our previous opinions that such procedures should be used only at the end of a sequential program of treatment.It is now felt that extirpation is only contraindicated in menopausal women with a duration of disease less than two years or when there is symptomatic disease of vital organs. Otherwise, early extirpation is recommended. When vital organ involvement is recognized in the asymptomatic stage or when screening of premenopausal women by castration indicates continuing hormonal dependency, then early extirpation is indicated.Both the qualitative and the quantitative responses achieved exceed those obtained by other measures when widely disseminated disease is present. The objective remission rate (34% after adrenalectomy and 19% after hypophysectomy) for longer than six months is worth while.     

Identification of cellular and subcellular features by means of digital microscopy

This paper presents two examples of the application of quantitative digital microscopy to two different fields of biological analysis: DNA content determination in microstructures and the study of the behaviour of microorganisms. In both cases the application of segmentation and labelling procedures was found to be essential in order to obtain the desired results, because it made it possible to overcome the measurement limits of traditional instrumentation and to obviate drawbacks normally present when analysis is placed in the hands of the human operator.     

Behavioral and physiological flexibility are used by birds to manage energy and support investment in the early stages of reproduction

Interest in phenotypic flexibility has increased dramatically over the last decade, but flexibility during reproduction hasreceived relatively little attention from avian scientists, despite its possible impact on fitness. Because most avian species maintainatrophied reproductive organs when not active, reproduction in birds requires major tissue remodeling in preparation for breeding.Females undergo rapid (days) recrudescence and regression of their reproductive organs at each breeding attempt, while m...     

Testing for marginal independence between two categorical variables with multiple responses

Questions that ask respondents to "choose all that apply" from a set of items occur frequently in surveys. Categorical variables that summarize this type of survey data are called both pick any/c variables and multiple-response categorical variables. It is often of interest to test for independence between two categorical variables. When both categorical variables can have multiple responses, traditional Pearson chi-square tests for independence should not be used because of the within-subject dependence among responses. An intuitively constructed version of the Pearson statistic is proposed to perform the test using bootstrap procedures to approximate its sampling distribution. First- and second-order adjustments to the proposed statistic are given in order to use a chi-square distribution approximation. A Bonferroni adjustment is proposed to perform the test when the joint set of responses for individual subjects is unavailable. Simulations show that the bootstrap procedures hold the correct size more consistently than the other procedures.     

In vivo replication of the hamster polyomavirus genome and generation of specific deletions in the process of lymphomagenesis.

Hamster polyomavirus (HaPV) causes lymphomas when injected into newborn hamsters. These tumors are virus-free but accumulate large amounts of deleted extrachromosomal viral genomes. In order to identify the major sites of virus replication in animals, we have monitored the HaPV DNA present in different organs at various times after injection. The data demonstrate that viral replication preferentially occurs in lymphoid organs. Lymphoma-associated viral genomes display specific deletions. PCR analysis shows that such viral genomes are the only variants detectable in infected animals, suggesting that they are generated by a specific cellular mechanism. We have tested the possible role of the lymphoid cell-specific V(D)J recombination activity in the generation of these specific variants. Our results indicate that this mechanism is not solely responsible for the viral genome rearrangement, if involved at all.     

Effect of abdominal compression on diaphragmatic tendon organ activity.

Previous studies suggest that afferents in the diaphragm participate in the reflex reduction in phrenic nerve efferent activation when the length of the diaphragm is increased by abdominal compression. The present study determined the response of tendon organ afferents in the diaphragm to increases in abdominal pressure. Five cats were anesthetized with thiopental sodium (60 mg/kg ip to induce, supplemented intravenously). Extracellular recordings from nine individual tendon organ afferents were made from right cervical dorsal root ganglia 5 and 6. Right crural electromyographic activity was recorded. The right extrathoracic phrenic nerve was isolated and stimulated to identify tendon organs on the basis of conduction velocity and response to twitch. The response to ramp-and-hold stretch of the diaphragm was used as an additional test to differentiate tendon organs from muscle spindles. The mean level of activity of the tendon organs during the 1st s of the inspiratory phase was 47 +/- 10 (SD) Hz. Abdominal compression was associated with a significant increase in the activity of these afferents to 61 +/- 11 Hz. Results indicate that increases in the activity of diaphragmatic tendon organs are associated with moderate increases in abdominal pressure and are likely the result of elevations in the active tension developed by the diaphragm. Combined with results from previous studies, it is possible that diaphragmatic tendon organs may play a role in the attenuation of respiratory muscle activation when abdominal pressure is increased.     

IS POST‐MORTEM HARM POSSIBLE? UNDERSTANDING DEATH HARM AND GRIEF

The purpose of this article is not to affirm or deny particular philosophical positions, but to explore the limits of intelligibility about what post-mortem harm means, especially in the light of improper post-mortem procedures at Bristol and Alder Hey hospitals in the late 1990s. The parental claims of post-mortem harm to dead children at Alder Hey Hospital are reviewed from five different philosophical perspectives, eventually settling on a crucial difference of perspective about how we understand harm to the dead. On the one hand there is the broadly 'analytical' tradition ¹ of thinking that predicates the notion of harm on the basis of an existing subject. Since the dead are non-existent persons, it makes little sense to view the dead as being harmed. On the other hand, there is a phenomenological perspective, where the dead, in respect to the experience of grief, are existentially absent. This forms the basis that it is possible to harm grieving parent's experiences of how their dead are treated. The article ends with a short examination of what harming the dead implies for traditional bioethical concerns, namely, obtaining informed consent from significant others when planning medical research on the newly dead.     

Mosaic pattern and lineage analysis in chimeras

Mammalian chimeras have been used in a number of developmental studies over the years. A major limitation in these studies has been the lack of in situ procedures for establishing mosaic pattern in the tissues of these animals. Recently, a number of procedures have become available for the histochemical demonstration of mosaicism in chimeras. These include the elucidation of various enzymes, receptors, or surface antigens, which have variant expression between strains. The observation of pattern in organs of mosaic animals can suggest possible modes of organogenesis and organ maintenance. Experimentation with such animals can be used to establish some mechanisms of pathogenesis as well.     

Biomechanical properties of abdominal organs in vivo and postmortem under compression loads

Accurate knowledge of biomechanical characteristics of tissues is essential for developing realistic computer-based surgical simulators incorporating haptic feedback, as well as for the design of surgical robots and tools. As simulation technologies continue to be capable of modeling more complex behavior, an in vivo tissue property database is needed. Most past and current biomechanical research is focused on soft and hard anatomical structures that are subject to physiological loading, testing the organs in situ. Internal organs are different in that respect since they are not subject to extensive loads as part of their regular physiological function. However, during surgery, a different set of loading conditions are imposed on these organs as a result of the interaction with the surgical tools. Following previous research studying the kinematics and dynamics of tool/tissue interaction in real surgical procedures, the focus of the current study was to obtain the structural biomechanical properties (engineering stress-strain and stress relaxation) of seven abdominal organs, including bladder, gallbladder, large and small intestines, liver, spleen, and stomach, using a porcine animal model. The organs were tested in vivo, in situ, and ex corpus (the latter two conditions being postmortem) under cyclical and step strain compressions using a motorized endoscopic grasper and a universal-testing machine. The tissues were tested with the same loading conditions commonly applied by surgeons during minimally invasive surgical procedures. Phenomenological models were developed for the various organs, testing conditions, and experimental devices. A property database-unique to the literature-has been created that contains the average elastic and relaxation model parameters measured for these tissues in vivo and postmortem. The results quantitatively indicate the significant differences between tissue properties measured in vivo and postmortem. A quantitative understanding of how the unconditioned tissue properties and model parameters are influenced by time postmortem and loading condition has been obtained. The results provide the material property foundations for developing science-based haptic surgical simulators, as well as surgical tools for manual and robotic systems.     

Spatial and temporal expression of an epithelial mucin, Muc-1, during mouse development.

The Muc-1 mucin is found as a transmembrane protein in the apical surface of glandular epithelia. To provide insight into possible functions, we have assessed the timing of expression and the distribution of the Muc-1 protein during mouse embryogenesis using three different techniques: RT-PCR, northern blots and immunohistochemistry. Our results indicate that Muc-1 expression correlates with epithelial differentiation in stomach, pancreas, lung, trachea, kidney and salivary glands. Once started, Muc-1 synthesis continually increases with time, mainly due to epithelial area growth. Our data suggest that expression of the Muc-1 gene is under spatial and temporal control during organogenesis. Although Muc-1 is present in different organs, its expression is not induced systemically, but according to the particular onset of epithelial polarization and branching morphogenesis of each individual organ. It is of particular interest that Muc-1 protein can be detected lining the apical surfaces of the developing lumens when the epithelium of these organs is still undergoing folding and branching, and glandular activity has not yet started. We speculate that Muc-1 may participate in epithelial sheet differentiation/lumen formation during early development of the organs known to express it. This speculation is based on: (1) the detection of Muc-1 expression early during organogenesis, (2) the defined apical localization in different epithelia, (3) the decrease in cell-cell interactions when Muc-1 protein is highly expressed and (4) the possible interaction of its cytoplasmic tail with the actin cytoskeleton. However, it remains to be established using in vitro systems, whether the temporal and local expression of the Muc-1 gene coincident with the morphogenetic events described here is relevant for the process.     

The subcellular fractionation of embryonic chick tendon and cartilage cells: a re-examination.

A re-examination of the subcellular fractions obtained from matrix-free chick tendon and cartilage cells has been made since the discovery that three out of four of the micrographs of chick tendon microsomal fractions published in an earlier paper from this laboratory were not authentic. The present studies demonstrate that by using the procedures previously reported it is possible to isolate microsomal and submicrosomal fractions from tendon and cartilage cells which exhibit typical morphology when examined by electron microscopy. These observations are consistent with our original biochemical characterization of subcellular fractions, which we know to be valid. Other publications from this laboratory in which these fractionation procedures have been applied to studies of collagen biosynthesis are in no way compromised, and indeed, most of our data have been confirmed by several other laboratories.     

Human communication with pigs: The behavioural response of pigs to specific human signals

A knowledge of the influence of behavioural and non-behavioural characteristics of humans on the behavioural responses of pigs to humans is required for the development of approach and handling procedures by stockpersons which achieve and maintain human—animal relationships in which the animals are not fearful of humans.Three experiments were conducted to compare the nature of several possible signals which humans may release when interacting with pigs. The nature of the signals was compared by quantifying the approach behaviour of the pig to the experimenter releasing the appropriate signals in four 3-min tests over an 8-day period. Pigs approached the experimenter significantly more (P < 0.05) when he did not approach, squatted, had bare hands or did not initiate interactions compared with when he did approach, stood erect, had gloved hands or initiated interactions with the pig, respectively.     

The Problem of Characters Susceptible to Parallel Evolution in Phylogenetic Reconstructions: Suggestion of a Practical Method and Its Application to Cave Animals

We here propose a procedure to treat characters which are susceptible to parallel evolution (in this case, troglomorphisms) as a replacement for the two procedures used so far: to either completely consider or completely disregard these characters. These procedures may lead to one of two opposite errors, respectively, (1) to consider them as true synapomorphies when they are not or (2) to disregard them as true synapomorphies when they are. We suggest herein to recode the characters by splitting each troglomorphic character into as many as the number of taxa which show the given troglomorphic state. For each split character each taxon will have the derived state, while the others will be coded as missing data. We provide three real examples to test our procedure and conclude that it may give results different from those of the other two procedures. This means that our procedure does not repeat the two above "errors." In addition, we believe that the procedure filters the possible biases, resulting in trees in which the troglomorphisms do have phylogenetic signals.     

Hearing in tiger beetles (Cicindelidae)

ABSTRACT. Tympanic hearing organs (ears) are reported for several tiger beetle (Cicindelidae) species. The paired ears are positioned bilaterally on the first abdominal tergum and consist of cavities covered by thin tympana. When the beetle is not flying the elytra covers its ears and reduces their sensitivity to sound. However, when the beetle is flying, its exposed ears are capable of detecting ultrasonic pulses. Under a microscope, beetles with their elytra artificially raised contract their abdomens in response to ultrasound. Ultrasonic emissions directed toward flying beetles induce them immediately to fly downward and land, a response which probably aids escape from predators, particularly echolocating bats. Other possible uses for the ears are the avoidance of diurnal insect predators and intraspecific communication.     

On the distribution of plant abundance data

Plant abundance data are often analysed using standard statistical procedures without considering their distributional features and the underlying ecological processes. However, plant abundance data, e.g. when measured in biodiversity monitoring programs, are often sampled using a hierarchical sampling procedure, and since plant abundance data in a hierarchical sampling procedure are typically both zero-inflated and over-dispersed, the use of a standard statistical procedure is sub-optimal and not the best possible practice in the modelling of plant abundance data. Two distributions (the zero-inflated generalised binomial distribution and the zero-inflated bounded beta distribution) are suggested as possible distributions for analysing either discrete, continuous, or ordinal hierarchically sampled plant cover data.