Synaptic communication mediates the assembly of a self-organizing circuit that controls reproduction

Migration of gonadotropin-releasing hormone (GnRH) neurons from their birthplace in the nasal placode to their hypothalamic destination is critical for vertebrate reproduction and species persistence. While their migration mode as individual GnRH neurons has been extensively studied, the role of GnRH-GnRH cell communication during migration remains largely unexplored. Here, we show in awake zebrafish larvae that migrating GnRH neurons pause at the nasal-forebrain junction and form clusters that act as interhemisphere neuronal ensembles. Within the ensembles, GnRH neurons create an isolated, spontaneously active circuit that is internally wired through monosynaptic glutamatergic synapses into which newborn GnRH neurons integrate before entering the brain. This initial phase of integration drives a phenotypic switch, which is essential for GnRH neurons to properly migrate toward their hypothalamic destination. Together, these experiments reveal a critical step for reproduction, which depends on synaptic communication between migrating GnRH neurons.

Simple Syntheses of New Pegylated Trehalose Derivatives as a Chemical Tool for Potential Evaluation of Cryoprotectant Effects on Cell Membrane

In our work, we developed the synthesis of new polyfunctional pegylated trehalose derivatives and evaluated their cryoprotective effect using flow cytometry. We showed that new compounds (modified trehaloses) bound to appropriate extracellular polymeric cryoprotectants could be helpful as a chemical tool for the evaluation of their potential toxic cell membrane influences. Our aim was to form a chemical tool for the evaluation of cryoprotectant cell membrane influences, which are still not easily predicted during the freezing/thawing process. We combined two basic cryoprotectants: polyethyleneglycols (PEGs) and trehalose in the new chemical compounds—pegylated trehalose hybrids. If PEG and trehalose are chemically bound and trehalose is adsorbed on the cell surface PEGs molecules which are, due to the chemical bonding with trehalose, close to the cell surface, can remove the cell surface hydration layer which destabilizes the cell membrane. This was confirmed by the comparison of new material, PEG, trehalose, and their mixture cryoprotective capabilities.

Changes in Cryopreserved Cell Nuclei Serve as Indicators of Processes during Freezing and Thawing

The mechanisms underlying cell protection from cryoinjury are not yet fully understood. Recent biological studies have addressed cryopreserved cell survival but have not correlated the cryoprotection effectiveness with the impact of cryoprotectants on the most important cell structure, the nucleus, and the freeze/thaw process. We identified changes of cell nuclei states caused by different types of cryoprotectants and associate them with alterations of the freeze/thaw process in cells. Namely, we investigated both higher-order chromatin structure and nuclear envelope integrity as possible markers of freezing and thawing processes. Moreover, we analyzed in detail the relationship between nuclear envelope integrity, chromatin condensation, freeze/thaw processes in cells, and cryopreservation efficiency for dimethyl sulfoxide, glycerol, trehalose, and antifreeze protein. Our interdisciplinary study reveals how changes in cell nuclei induced by cryoprotectants affect the ability of cells to withstand freezing and thawing and how nuclei changes correlate with processes during freezing and thawing. Our results contribute to the deeper fundamental understanding of the freezing processes, notably in the cell nucleus, which will expand the applications and lead to the rational design of cryoprotective materials and protocols.

Cryopreserved Cells Regeneration Monitored by Atomic Force Microscopy and Correlated With State of Cytoskeleton and Nuclear Membrane

Atomic force microscopy (AFM) helps to describe and explain the mechanobiological properties of living cells on the nanoscale level under physiological conditions. The stiffness of cells is an important parameter reflecting cell physiology. Here, we have provided the first study of the stiffness of cryopreserved cells during post-thawing regeneration using AFM combined with confocal fluorescence microscopy. We demonstrated that the nonfrozen cell stiffness decreased proportionally to the cryoprotectant concentration in the medium. AFM allowed us to map cell surface reconstitution in real time after a freeze/thaw cycle and to monitor the regeneration processes at different depths of the cell and even different parts of the cell surface (nucleus and edge). Fluorescence microscopy showed that the cytoskeleton in fibroblasts, though damaged by the freeze/thaw cycle, is reconstructed after long-term plating. Confocal microscopy confirmed that structural changes affect the nuclear envelopes in cryopreserved cells. AFM nanoindentation analysis could be used as a noninvasive method to identify cells that have regenerated their surface mechanical properties with the proper dynamics and to a sufficient degree. This identification can be important particularly in the field of in vitro fertilization and in future cell-based regeneration strategies.

Chromatin architecture changes and DNA replication fork collapse are critical features in cryopreserved cells that are differentially controlled by cryoprotectants

In this work, we shed new light on the highly debated issue of chromatin fragmentation in cryopreserved cells. Moreover, for the first time, we describe replicating cell-specific DNA damage and higher-order chromatin alterations after freezing and thawing. We identified DNA structural changes associated with the freeze-thaw process and correlated them with the viability of frozen and thawed cells. We simultaneously evaluated DNA defects and the higher-order chromatin structure of frozen and thawed cells with and without cryoprotectant treatment. We found that in replicating (S phase) cells, DNA was preferentially damaged by replication fork collapse, potentially leading to DNA double strand breaks (DSBs), which represent an important source of both genome instability and defects in epigenome maintenance. This induction of DNA defects by the freeze-thaw process was not prevented by any cryoprotectant studied. Both in replicating and non-replicating cells, freezing and thawing altered the chromatin structure in a cryoprotectant-dependent manner. Interestingly, cells with condensed chromatin, which was strongly stimulated by dimethyl sulfoxide (DMSO) prior to freezing had the highest rate of survival after thawing. Our results will facilitate the design of compounds and procedures to decrease injury to cryopreserved cells.

AFM Monitoring the Influence of Selected Cryoprotectants on Regeneration of Cryopreserved Cells Mechanical Properties

Cryopreservation of cells (mouse embryonic fibroblasts) is a fundamental task for wide range of applications. In practice, cells are protected against damage during freezing by applications of specific cryoprotectants and freezing/melting protocols. In this study by using AFM and fluorescence microscopy we showed how selected cryoprotectants (dimethyl sulfoxide and polyethylene glycol) affected the cryopreserved cells mechanical properties (stiffness) and how these parameters are correlated with cytoskeleton damage and reconstruction. We showed how cryopreserved (frozen and thawed) cells' stiffness change according to type of applied cryoprotectant and its functionality in extracellular or intracellular space. We showed that AFM can be used as technique for investigation of cryopreserved cells surfaces state and development ex vivo. Our results offer a new perspective on the monitoring and characterization of frozen cells recovery by measuring changes in elastic properties by nanoindentation technique. This may lead to a new and detailed way of investigating the post-thaw development of cryopreserved cells which allows to distinguish between different cell parts.

Theoretical and experimental study of the antifreeze protein AFP752, trehalose and dimethyl sulfoxide cryoprotection mechanism: correlation with cryopreserved cell viability

In this work the physico-chemical properties of selected cryoprotectants (antifreeze protein TrxA-AFP752, trehalose and dimethyl sulfoxide) were correlated with their impact on the constitution of ice and influence on frozen/thawed cell viability. The freezing processes and states of investigated materials solutions were described and explained from a fundamental point of view using ab-initio modelling (molecular dynamics, DFT), Raman spectroscopy, Differential Scanning Calorimetry and X-Ray Diffraction. For the first time, in this work we correlated the microscopic view (modelling) with the description of the frozen solution states and put these results in the context of human skin fibroblast viability after freezing and thawing. DMSO and AFP had different impacts on their solution's freezing process but in both cases the ice crystallinity size was considerably reduced. DMSO and AFP treatment in different ways improved the viability of frozen/thawed cells.

Fifteen years of the Family Eating and Activity Habits Questionnaire (FEAHQ): an update and review

BACKGROUND

The Family Eating and Activity Habits Questionnaire (FEAHQ) is a 32-item self-report instrument designed to assess the eating and activity habits of family members as well as obesogenic factors in the overall home environment (stimulus and behaviour patterns) related to weight. Originally, this questionnaire, which was developed in Israel, was designed for use in family-based weight-management interventions that emphasized changes in the environment, and in parents' knowledge, behaviours and modelling. It was developed for use with children aged 6-11 years and designed for co-completion by parents or caretakers and their children. Over the years, it has been administered in research and clinical settings in Israel, England, Australia and other countries. Its 15-year anniversary calls for an update in the literature regarding adjustments made to improve its use in different settings and with different ethnic populations and the psychometric properties of the revised version.

OBJECTIVE

The goal of this paper is threefold: (i) to describe the history and development of the FEAHQ; (ii) to present new data supporting the psychometric properties of the subscales of the Revised FEAHQ (FEAHQ-R) for ages 6-12 years and (iii) to review the clinical and research literature reporting on FEAHQ subscales.

METHODS

The psychometric properties of the revised questionnaire were evaluated in a randomized control trial and in a naturalistic, community-based study to promote healthy lifestyle among families with children 6-12 years of age from different ethnic populations.

RESULTS

The tool demonstrated good test-retest reliability when completed by caretakers and very good internal consistency. The questionnaire scores discriminated between obese and normal-weight children and predicted the weight classification of 66% of the participants.

CONCLUSIONS

The FEAHQ-R is a useful clinical tool for identifying target behaviors for treatment and monitoring treatment progress that centers on overweight prevention and weight management.

Mitochondrial VDAC1: function in cell life and death and a target for cancer therapy

Found at the outer mitochondrial membrane, the voltage-dependent anion channel, VDAC, assumes a crucial position in the cell, serving as the main interface between mitochondrial and cellular metabolisms by mediating transport of ions and metabolites. VDAC thus functions as a gatekeeper, controlling cross-talk between mitochondria and the rest of the cell. Moreover, its location at the boundary between the mitochondria and the cytosol enables VDAC to interact with proteins that mediate and regulate the integration of mitochondrial functions with other cellular activities. Here, we review current knowledge related to the roles played by VDAC in the regulation of cell life and cell death, with relation to cancer. The current concepts of altered metabolism in cancer cells are presented with specific emphasis on mitochondrial, more specifically VDAC1-bound hexokinase (HK), facilitating and promoting the high glycolytic tumor phenotype. In this respect, the up-regulation of HK expression in tumor cells and its binding to VDAC provide both a metabolic benefit and apoptosis-suppressive capacity that offers the cell a growth advantage and increases its resistance to chemotherapy. VDAC has also been recognized as a key protein in mitochondria-mediated apoptosis since it is the proposed target for the pro- and antiapoptotic Bcl-2-family of proteins, as well as due to its function in the release of apoptotic proteins located in the inter-membranal space. These and other functions point to VDAC1 as being a rational target for the development of a new generation of therapeutics.

Protective self-presentation style: association with disordered eating and anorexia nervosa mediated by sociocultural attitudes towards appearance

OBJECTIVE

We tested the hypothesis that a protective self-presentation style (Lennox and Wolfe, 1984) is associated with eating pathology and anorexia nervosa (AN) and that this association is mediated by sociocultural attitudes towards appearance emphasizing the thin ideal.

METHOD

We compared the protective-presentation style of women with AN (N=17), partially recovered women (N=110), fully recovered women (N=73), and female controls (N=374).

RESULTS

Ill women had a more protective self-presentation style than partially or fully recovered women, who in turn had a more protective self-presentation style than controls. Sociocultural attitudes towards appearance fully mediated the association between protective self-presentation and disordered eating.

CONCLUSIONS

Protective self-presentation may therefore be a risk factor for AN and/or a prognostic factor. Implications for therapy and prevention are discussed.

[Criteria for hospitalization of adolescents with anorexia nervosa according to postmodernistic approach]

The increased incidence of eating disorders in the Western world raises the demand for discussion regarding recommendations for hospitalization of adolescents with these disorders. The American Psychiatric Association has established criteria for hospitalization that include physiological, psychological and social components. The societal and professional discussion regarding adolescent hospitalization is frequently based on obvious assumptions and accepted discourses, such as the hierarchical pattern in the medical model, the control perception, knowledge ownership, freedom of choice, etc. These issues challenge the discussion on the hospitalization of adolescents with eating disorders. Eating disorders involve dimensions of control, boundaries, and psychological space, which are the essence of the difference between therapy in hospital or in the community. Personality and personal patterns, as well as associated psychopathology, family structure and other factors influence these dimensions and the ability of teenagers to be helped by the professional frameworks approached by them. This manuscript raises questions in relation to issues regarding hospitalization based on conflicts unique to eating disorders.

The -22c/t polymorphism in presenilin 1 gene is not connected with late-onset and early-onset familial Alzheimer's disease in Poland

The -22c/t polymorphism in the promoter of the presenilin 1 gene is associated with increased risk for Alzheimer's disease (AD) in some populations. It was shown that -22c allele is connected with two-fold decrease in promoter activity. We studied the impact of the polymorphism in groups of Polish late-onset and early-onset AD patients. Our results suggest that -22c/t polymorphism is not connected with AD in Polish population. The -22t allele showed a high degree of linkage disequilibrium with -2797 insertion of 13 bp. An additional -2923g/t polymorphism is also not connected with -22c/t and is not a risk factor for AD.

[Clinical mentorship as a bridge to life in the treatment of eating disorders]

The aim of this article is to describe a community-based multi-modality intensive treatment program, which demonstrates a significant reduction in symptoms of eating disorders while providing an opportunity to deal with the functional and social skills. Treatment is delivered through a multidisciplinary team. The uniqueness of the team is in the inclusion of clinical mentors. These are social workers, art therapists and graduate level psychology students who are trained to connect with clients in an informal, intensive manner (10-40 hours a week). The mentors focus on legitimizing healthy attitudes to food, eating and life, while highlighting the pain and loss associated with the disorder. The mentors serve as meal companion and calming figure, representing the healthy self-caring voice. The relationship established during the many hours spent together becomes a powerful experience, completely different from the isolation of the disorder. The treatment intervenes in most areas of life, focusing on an active search for possibilities, in contrast to the emptiness associated with the disorder. This article presents the results and principles of a 2.5-year practice. Seventeen patients, ill for 6 years and more, completed this program more than a year ago. An assessment of their BMI and their general outcome using Eckert scales was performed. One year after completing the program, 76% of the patients were defined as recovered and 12% were almost recovered with only a few remaining symptoms. All of these patients function satisfactorily in the community, both in social and occupational aspects. Six percent were partially recovered and 6% suffered from regression during the first year of follow-up. This treatment provides the intensity required in hospitalizations, while enabling patients to stay in the community and maintain those activities that survive the disorder. This program has proven to work well with chronic patients. Further data, not analyzed as yet, also indicates the efficacy of this treatment in acute cases.

Familial approach to the treatment of childhood obesity: conceptual mode

This model for the management of childhood obesity uses a family-based approach. Change is delivered through the parents (instead of the obese child) emphasizing a healthy lifestyle and not weight reduction as in previously published, family-based management of childhood obesity. This intervention integrates behavioral, social learning, and family system approaches. The proposed approach includes changes in parental cognition, emphasizing "parenthood presence"; parents serve both as a source of authority and a role model for the obese child, providing a family environment that fosters healthy practices related to weight control issues and de-emphasizing personal responsibility for control of health behavior.

Impact of treatment for childhood obesity on parental risk factors for cardiovascular disease

BACKGROUND

Family-based approaches using the parents as agents of change to treat childhood obesity are superior to programs targeting only children in achieving weight reduction and have a lower dropout rate.

OBJECTIVE

The aim of this study was to compare the impact of two behavioral approaches (parents only vs children only) for the treatment of childhood obesity on parental weight, eating, and activity habits as well as cardiovascular risk factors.

DESIGN

A randomized 1-year clinical intervention study was performed.

METHODS

Sixty obese children (>/=20% over ideal weight for age, height, and sex), ages 6-11 years, were randomly allocated to the experimental (parents as sole agents of change) or conventional groups (children as sole agents of change). Fourteen (1-h-long) support/educational sessions were conducted by a clinical dietitian for the parents in the experimental group and 30 sessions for children in the conventional group. Anthropometric and biochemical measurements were determined at the start and end of the program.

RESULTS

The experimental approach, when compared to the conventional intervention, was found to be superior in the reduction of fathers overweight (P < 0.05). The former approach resulted also in improved profile of risk factors for cardiovascular disease in both parents. These changes could be ascribed to a greater improvement in eating and activity behaviors observed in parents belonging to the experimental intervention group who participated in a family-based intervention to treat their children's obesity.

CONCLUSIONS

Treatment of childhood obesity targeting the parents as the sole agent of change, which is more effective for the treatment of childhood obesity when compared to a children-oriented program, may in addition award parents with the benefit of changing their own eating and activity patterns, thus making this program ideal for treatment of obesity in children and their overweight parents.

Role of behaviour modification in the treatment of childhood obesity with the parents as the exclusive agents of change

OBJECTIVE

This study examined the reduction in overweight and changes in eating-related behaviours in obese children treated with a family-based approach, in which the parents were the exclusive agents of change. Results were compared to the conventional approach in which children are responsible for their own weight loss.

DESIGN

A one-year longitudinal prospective design was used. Participants were randomly allocated for the experimental (parents as the agents of change) or the conventional (children as the agents of change) intervention.

METHODS

Sixty obese children (20% over ideal weight for age, height and gender) aged 6-11 y (mean+/-s.d. 9.2+/-1.0 y) were included in the study. Anthropometric measurements and biochemical tests were performed on the children and their parents before and after the programme, and both parents completed a sociodemographic and a family eating and activity habits questionnaire. Hour-long support/educational sessions were conducted by a clinical dietitian-14 sessions for the parents in the experimental intervention and 30 for the children in the conventional intervention. Individual sessions were held for members of both groups, when necessary.

RESULTS

Significant differences were found between the two groups in the reduction of exposure to food stimuli and changes in eating habits (eating while standing, watching TV, reading or doing homework, eating following stress and eating between meals). Mean weight reduction (by percentile) was significantly greater in the experimental intervention group (parent-only treatment) in comparison to the conventional intervention group (child-only treatment).

CONCLUSIONS

Treatment of childhood obesity with the parents as the exclusive agents of change, induces more behavioural changes as well as greater weight loss, than the conventional approach.

Reliability and validity of the Family Eating and Activity Habits Questionnaire

OBJECTIVE

The purpose of this work was to develop and test an instrument that will identify the factors that facilitate childhood obesity and monitor the environmental changes and family behavior modifications associated with weight loss.

DESIGN AND METHODS

The relevant factors that affect obesity and weight loss in children were divided into four scales: activity level, stimulus exposure, eating related to hunger, and eating style. We designed a questionnaire to be completed by the parents of the obese child aged 6-11 years. Scores accumulated were calculated separately for each member of the family. Higher numerical scores reflected less appropriate eating patterns. The questionnaire reliability (test-retest), internal consistency and ability to discriminate obese vs normal-weight children's behaviors was tested using a pilot population of 40 mothers not enrolled in a formal weight loss program. The questionnaire reliability (parents' report and spouse report) and predictive validity was tested using a selective population: 60 parents of obese children enrolled in a clinical intervention intended to treat childhood obesity with an environmental approach vs a dietary approach.

RESULTS

The content validity of the questionnaire was evaluated by a team of ten experts. Cronbach's alpha was calculated to test internal consistency. Mean r was 0.83. Pearson's correlation coefficients were computed between test and retest scores for individual items and for the total score, and ranged from 0.78 to 0.90 (median 0.84) (P < 0.01 for all). Total score test-retest r was 0.85 (P < 0.01). The total family score was also higher in the families with an obese child compared to families with a normal-weight child, P < 0.01. No significant differences were noted between parent report and spouse report scores. The construct validity of the questionnaire was also supported by its high sensitivity to weight loss treatment. Weight loss in the child correlated highly with improvement in questionnaire score.

CONCLUSIONS

The Family Activity and Eating Habits Questionnaire is reliable and internally consistent, and it is useful as an optional tool for planning an intervention program for childhood obesity.

Parents as the exclusive agents of change in the treatment of childhood obesity

BACKGROUND

Excessive weight in childhood is a serious public health concern because of its costly health consequences and its increasing prevalence.

OBJECTIVE

Our objective was to compare the efficacy of a family-based approach for the treatment of childhood obesity, in which the parents served as the exclusive agents of change, with that of the conventional approach, in which the children served as the agents of change.

DESIGN

This study had a randomized, longitudinal prospective design and lasted 1 y. Sixty obese children aged 6-11 y were randomly allocated to the experimental (parents as agents of change) or control (children as agents of change) group. Anthropometric and biochemical measurements were determined at the start and end of the study. A sociodemographic questionnaire and a family eating and activity habits questionnaire were completed by both parents. Hour-long support and educational sessions were conducted by a clinical dietitian: 14 sessions for the parents in the experimental group and 30 sessions for the children in the control group.

RESULTS

The dropout rate was nine times greater in the control group (n = 9) than in the experimental group (n = 1). Mean percentile weight reduction was significantly (P < 0.03) higher in children in the experimental group (14.6%) than in the control group (8.1%).

CONCLUSIONS

Treatment of childhood obesity with parents as the exclusive agents of change was superior to the conventional approach, as indicated by the dropout rate and the percentage weight loss of the children during the 1-y intervention.

[Angina pectoris as a symptom of gastric volvulus]

Angina pectoris is a common complaint in any emergency service, but it rarely is of extracardiac origin. A rare case of gastric volvulus which presented a recurrent angina pectoris in a 47-year-old man is reported. Repeated episodes of angina pectoris in a patient with a negative cardiac investigation should alert the physician to the possibility of extracardiac pathology.

Synergism between infarct-borne left ventricular dysfunction and cardiomegaly in increasing the risk of coronary bypass surgery

The effect of cardiomegaly on operative and late mortality in patients with left ventricular dysfunction undergoing coronary bypass operation was investigated. The study group consisted of 178 patients whose left ventricular ejection fraction was below 45% and who were operated on from 1978 through 1985. Forty-five patients (group A) had severe left ventricular dysfunction (ejection fraction < 30%) and 133 (group B) had moderate dysfunction (30% > ejection fraction > 45%). Twenty-four of group A (53%) and 54 of group B (41%) patients had cardiomegaly (cardiothoracic ratio on chest x-ray films > 0.5). There were 10 (6%) hospital deaths, four in group A (9%) and six in group B (4.5%). All four deaths in group A and the six deaths in group B were patients who had cardiomegaly. Regardless of the severity of the left ventricular dysfunction, there was no operative death among patients with normal heart size (p < 0.001). Age over 65, bypass time longer than 2 hours, and incomplete revascularization emerged as risk factors. Follow-up ranged from 5 to 13 years (mean 7.8 years). Overall 5-year actuarial survival, including hospital mortality, was 80% +/- 3%. Reduced 5-year survival was observed in patients with cardiomegaly (67% +/- 5% versus 91% +/- 3%, p < 0.05). Five- and 10-year survival of patients from group A with cardiomegaly was 53% +/- 7% and 18% +/- 13%, respectively.

Solid swallowing versus water swallowing: manometric study of dysphagia

The aim of the study was to investigate whether a soft solid bolus can induce abnormal manometric patterns in patients with dysphagia and normal standard manometry. The study group comprised 12 normal volunteers and 22 patients with dysphagia. Manometry was performed using 10 wet swallows followed by 10 swallows of marshmallow. The results show: (1) in normal subjects the mean contraction amplitude is significantly greater (P less than 0.035) and the velocity of propagation significantly slower (P less than 0.003) for soft solid swallows compared with wet swallows; (2) in normal subjects there are fewer abnormal contractions after soft solid swallows than after wet swallows; (3) in 15 patients, soft solid swallows induced non-peristaltic contractions and/or contractions of extreme amplitude and/or duration that were not observed after wet swallows; (4) in patients, the probability of inducing abnormal contractions after soft solid swallows is significantly greater than after wet swallows (P less than 0.0001). We conclude that soft solid swallowing is useful in the study of patients with dysphagia.

Penetrating thoracic wounds caused by plastic bullets

Thoracic penetrating injuries caused by a new plastic bullet were studied to determine the nature of the wounds and the appropriate management. Twenty-six casualties from the Israeli-Palestinian conflict (Intifada) were included. The organs most commonly involved were lung (n = 21), bony chest wall (n = 9), heart (n = 3), and diaphragm. Bleeding was at least moderate in 20 patients, amounting in all patients to an average of 975 ml. Thoracotomy was required in 11 patients (42%) mainly because of cardiac injury (n = 3) and aortic or other arterial bleeding (n = 3). Simple oversewing of severed organs (n = 8) or ligation of bleeding vessels (n = 3) was satisfactory. Two patients died (7.7% mortality); one after major liver resection; the other was dead on arrival. We conclude that plastic bullets have a linear course unless displaced by the bony chest wall, when they tend to fragment and cause simple fractures. Fired from a presumed range of at least 70 m, plastic bullets behave like low-velocity missiles, and tissue destruction is minimal. Management should be similar to that of civilian thoracic penetrating trauma.

Plastic bullet arterial embolization following gunshot injury to the heart. Case report and review of the literature

A plastic bullet penetrating the heart through the right ventricle embolized to the right profunda. Suture of the heart and extraction of the bullet resulted in uneventful recovery. The literature revealed 21 instances of embolization following proven heart penetration, in two cases through the right ventricle.

Transfusion of fresh whole blood stored (4 degrees C) for short period fails to improve platelet aggregation on extracellular matrix and clinical hemostasis after cardiopulmonary bypass

It has recently been shown that the hemostatic effect of 1 unit of fresh whole blood is equivalent to the effect of 8 to 10 platelet units. This study was designed to evaluate the effect of short periods of cold (4 degrees C) storage on the hemostatic effect of fresh whole blood transfusion in 36 patients immediately after cardiopulmonary bypass. Twelve patients (group A) received unrefrigerated fresh whole blood, 12 (group B) received fresh whole blood after 5 hours' storage at 4 degrees C, and 12 (group C) after 24 hours' storage at 4 degrees C. For evaluation of platelet function, a method with an extracellular matrix and an electron microscope was used. The platelet function was graded from 1 to 4, with grade 4 being normal aggregation. Postoperatively, group A patients bled less than groups B and C (267 +/- 42 versus 397 +/- 72 and 601 +/- 172 ml/24 hr, respectively, p less than 0.001) and therefore received fewer blood units (1.4 +/- 0.5 versus 2 +/- 0.9 and 3 +/- 1.4, respectively, p less than 0.01). Five patients of group A (42%) reached grade A aggregation after transfusion of unstored fresh whole blood, compared with two (17%) of group B and none (0%) of group C (p less than 0.01). Posttransfusion platelet count and mean platelet volume were not significantly different in the three groups. We conclude that storage at 4 degrees C, even for a short period of 5 hours, diminishes the hemostatic effect of fresh whole blood by decreasing platelet aggregability.

The effect of transfusion of fresh whole blood versus platelet concentrates after cardiac operations. A scanning electron microscope study of platelet aggregation on extracellular matrix

To evaluate the effect of fresh whole blood transfusion versus platelet concentrates transfusion on platelet aggregation after cardiac operations, 24 patients were randomized to receive either one unit of fresh whole blood (12 patients) or 10 platelet units (12 patients) after cardiopulmonary bypass. Platelet aggregation on extracellular matrix, platelet count, and mean platelet volume were studied preoperatively, at termination of cardiopulmonary bypass, after protamine administration, and after the transfusion of fresh whole blood or after transfusion of each two platelet units. Extracellular matrix produced by cultured bovine corneal cells closely resembles the vascular subendothelial basal lamina, and is an ideal in vitro model in the study of platelet interaction with the subendothelium. Platelet aggregation on extracellular matrix, studied by a scanning electron microscope, was graded from 1 to 4, wherein grade 1 represents nonactivated platelets and grade 4 a mature platelet aggregate. With this grading system, the two groups were similar in preoperative values (3.3 +/- 0.9 versus 3.7 +/- 0.4) and values after cardiopulmonary bypass (1.5 +/- 1.0 in both groups). One unit of fresh whole blood restored platelet aggregation on extracellular matrix to preoperative status (3.0 +/- 1.0), whereas eight platelet units were needed for the same result (3.2 +/- 0.8). One unit of fresh whole blood increased platelet count in a manner similar to that achieved by six platelet units and increased mean platelet volume to a level higher than that achieved by 10 platelet units. These results suggest that the effect of one unit of fresh whole blood on platelet aggregation after cardiopulmonary bypass is at least equal, if not superior, to the effect of 8 to 10 platelet units.

Studies of manometric abnormalities of the rectoanal region during defecation in constipated and soiling children: modification through biofeedback therapy

Anorectal manometry was performed on 12 normal children and 18 patients suffering from constipation and soiling. In both groups, the results of the rectoanal inhibitory reflex and the squeezing anal pressure were similar. The pressure recording in all the normal children showed that the anal canal relaxed during defecation. Fourteen (78%) constipated children closed the anal canal while straining by contracting the anal sphincter. This paradoxical contraction appears to be the cause of chronic constipation. Twelve children with paradoxical anal closure were treated by biofeedback therapy. The results show that all these children were successfully conditioned to relax their anal sphincter during defecation. This therapy improved their bowel habits and relieved them from constipation and soiling. It is proposed that the paradoxical anal closure itself is the result of a self-conditioning process. In this process, the patient learns to paradoxically contract the external anal sphincter in response to the urge and the act of defecation. Biofeedback therapy seems to be the appropriate treatment in such cases.

Coronary artery bypass surgery in a cadaver kidney transplant recipient

A review of the literature revealed that reports on coronary bypass operations in post renal transplant patients are rare. Here a case of successful coronary by-pass operation in a renal transplant patient is reported.

Platelet size and mass as an indicator for platelet transfusion after cardiopulmonary bypass

Platelet count, mean platelet volume (MPV), and plateletcrit (PCT) were studied in 51 patients after cardiopulmonary bypass (CPB). MPV was significantly lower in 10 patients who developed postoperative bleeding (bleeders) compared to 41 with no significant bleeding (nonbleeders) (7.7 +/- 0.86 vs 8.5 +/- 1.2 fl, p less than .05). Postoperative platelet count was significantly lower in the group of bleeders (93.3 +/- 22.4 vs 127.5 +/- 43 X 10(9)/liters, p less than .02). A cutoff point of MPV or platelet count that would include bleeders and exclude nonbleeders could not be found due to the large overlap between the two groups. However, such a cutoff point does exist for PCT (PCT = total platelet mass). PCT was significantly lower among the bleeders (0.072 +/- 0.02% vs 0.108 +/- 0.036%, p less than .05) and a cutoff point of PCT less than 0.1% included all the bleeders and excluded 65% of nonbleeders. The low PCT and bleeding tendency can be corrected by platelets transfusion. In 15 patients (eight bleeders and seven nonbleeders) with low postoperative PCT (0.078 +/- 0.014), transfusion of 10 platelet units increased platelet count from 101 +/- 32 to 169 +/- 22 X 10(9)/liter, increased PCT to 0.128 +/- 0.2%, and stopped bleeding in all bleeders. A finding of PCT less than 0.1% after CPB is a clear indication for platelet transfusion in patients who develop post-CPB bleeding. This supports the observation that large platelets are more active than smaller ones, and that PCT, rather than PLT counts, predicts the risk of bleeding in patients with thrombocytopenia.

Effect of cardiac operation on platelets

The effect of extracorporeal circulation on platelet count and size (mean platelet volume) was studied in 65 patients (nine bleeders and 56 nonbleeders). In addition to the above, in 20 of the patients platelet aggregation response to adenosine diphosphate, collagen, and ristocetin was measured. Platelet counts dropped postoperatively both in the bleeder and in the nonbleeder groups. The difference between them was not significant. However, the bleeders had a significantly lower mean platelet volume (7.7 +/- 0.84 versus 8.68 +/- 1.1 fl) and lower volume percentage of platelets in whole blood (0.075% +/- 0.02% versus 0.116% +/- 0.04%) (p less than 0.05) than the nonbleeders. None of the bleeders had a volume percentage of platelets in whole blood higher than 0.095%. All 20 patients studied for platelet functions had an abnormal postoperative aggregation response to adenosine diphosphate, collagen, and ristocetin. Three patterns of disturbed response to ristocetin were observed: grade I, delayed onset (14 patients); grade II, incomplete aggregation (five patients); and grade III, total lack of aggregation (one patient). All patients with delayed-onset response to ristocetin had a normal bleeding time, whereas the six patients with grade II and III responses had prolonged bleeding times and three of them had clinically significant bleeding. Factor VIII procoagulant activity, factor VIII-related antigen, factor VIII-ristocetin cofactor, and factor VIII two-dimensional electrophoresis were found normal, which suggests that the von Willebrand-like reaction to ristocetin observed in this study was caused by a defect in platelet membrane rather than by factor VIII changes.

Subclinical brachial plexopathy following median sternotomy

In order to detect subclinical cases of brachial plexus injury following open heart surgery through median sternotomy, 15 patients were included in this prospective study. Physical and electrophysiologic examinations were performed preoperatively and postoperatively. The axillary F-loop latency was used to diagnose the brachial plexopathy. No clinical symptoms were found in this group postoperatively. Of the 15 patients, 13 (87%) were found to have a postoperative subclinical brachial plexopathy, at least on one side, and in eight of the patients, it was present on both sides.

Metabolism of benzo(a)pyrene by subcellular fractions of rat liver: evidence for similar patterns of cytochrome P-450 in rough and smooth endoplasmic reticulum but not in nuclei and plasma membrane

Since our earlier work (P. Stasiecki, F. Oesch, G. Bruder, E.D. Jarasch, and W.W. Franke, Eur. J. Cell Biol., 21: 79-92, 1980) had shown that carcinogen-metabolizing monooxygenase activity was present in almost all investigated cellular membranes, the possibility of differential control of the various metabolic pathways in the individual cellular membranes arose. Using high pressure liquid chromatography we have now studied the benzo(a)pyrene metabolites formed by rough and smooth endoplasmic reticulum, nuclei, and plasma membrane as well as mitochondrial fractions and investigated the metabolic cooperation between the monooxygenases and epoxide hydrolase in these fractions. Since various cytochrome P-450 isozymes catalyze the oxidative attack on the benzo(a)pyrene molecule at defined preferential sites, this analysis also provides an indirect trace of potential differences in the pattern of cytochrome P-450 isozymes present in the individual membranes. The metabolic profiles produced by the two most active fractions, smooth and rough endoplasmic reticulum, were very similar to each other but different from those produced by the other three preparations. The metabolite pattern produced by incubations containing nuclear fractions differed slightly from that produced by the fractions of endoplasmic reticulum, but plasma membrane and mitochondria produced markedly different patterns. Since the similarity of the benzo(a)pyrene metabolite pattern produced by the smooth and rough endoplasmic reticulum suggested similar cytochrome P-450 isozyme patterns in these two subfractions, they were further investigated by the use of selective inducers as well as a broad spectrum substrate, 7-ethoxy-coumarin, in the absence and presence of selective inhibitors. Treatment of animals with trans-stilbene oxide or phenobarbital (a) increased the total amount of metabolites per protein mass and time, (b) changed the pattern of metabolites, but (c) induced a pattern of metabolites which was again very similar in rough and smooth endoplasmic reticulum. Even more distinct changes were found following treatment with 3-methylcholanthrene or beta-naphthoflavone. Both of these compounds (a) preferentially induced the activity of rough endoplasmic reticulum, (b) changed the profile of metabolites, but (c) again did not disturb the similarities of the benzo(a)pyrene metabolite pattern between both fractions.(ABSTRACT TRUNCATED AT 400 WORDS)

The mutagenicity of dibenz [a,h]anthracene activated by phenobarbital-inducible mouse-liver mono-oxygenase is potentiated by the presence of hydrophilic residues at the K-region of the molecule

Dibenz[a,h]anthracene and synthetic K-region derivatives of the parent hydrocarbon and of benz[a]anthracene were tested for mutagenicity by the reversion of histidine-dependent Salmonella typhimurium TA98, TA100 and TA1537. The K-region metabolite 5,6-dihydroxy-5,6-dihydrodibenz[a,h]anthracene, inactive as such, was efficiently activated to mutagens for TA98 and TA100 by mouse-liver 9000 X g supernatant or microsomal fraction. Microsomes from phenobarbital- or Aroclor-1254-treated mice were efficient for this activation, while those from untreated or beta-naphthoflavone-treated mice were much less active. A study on the influence of various structural features on this efficient activation by phenobarbital-inducible mono-oxygenase of mouse-liver microsomes showed that, if the K-region were saturated, no metabolism to mutagens occurred, while substitution of the K-region by carbonyl and hydroxyl substituents led to increased mutagenic efficacy with increasing hydrophilicity (dihydro less than carbonyl less than hydroxyl). The K-region epoxide was the only derivative that did not require metabolic activation and it had a markedly different mutagenic specificity in that it was also mutagenic for TA1537.

Specificity of mouse liver cytosolic epoxide hydrolase for K-region epoxides derived from polycyclic aromatic hydrocarbons

Mouse liver cytosol epoxide hydrolase, known to be very active for certain alkene oxides, had a specific activity which was 2.1-, 11- and 160-fold lower than that of the microsomal epoxide hydrolase for the arene oxides 7-methylbenz[a]anthracene 5,6-oxide, benz[a]anthracene 5,6-oxide and phenanthrene 9,10-oxide, respectively. For benzo[a]pyrene 4,5-oxide no activity (less than 10 pmol product/mg protein/min) of cytoplasmic epoxide hydrolase was detectable. The specific activity of cytoplasmic epoxide hydrolase was much lower for all K-region epoxides investigated, compared to trans-stilbene oxide used as a positive control and for which a new assay is described. It is concluded from these rates combined with the fact that these lipophilic K-region epoxides are expected to stay preferentially at membranous sites where they are generated, that cytoplasmic epoxide hydrolase plays a minor role for their transformation compared to membrane-bound hydrolase. The data also show that for the substrates investigated the epoxide hydrolase activities in the cytoplasmic and microsomal fractions are complementary to some extent, but there is no quantitative inverse relationship.