Kisspeptin is present in ovine hypophysial portal blood but does not increase during the preovulatory luteinizing hormone surge: evidence that gonadotropes are not direct targets of kisspeptin in vivo

There is strong evidence that kisspeptin acts to regulate GnRH secretion, but whether there is also a component of action on the gonadotropes is not clear. Using quantitative RT-PCR, we found that G protein-coupled receptor-54 mRNA is expressed in ovine pituitary cell fractions enriched for gonadotropes as well as in somatotropes and lactotropes. To test whether kisspeptin acts directly on the pituitary gonadotropes, we first examined LH release from primary ovine pituitary cell cultures treated with kisspeptin. We found that kisspeptin treatment increased the concentration of LH in culture media by 80%, compared with control, but only in pituitary cultures from ewes during the follicular phase of the estrous cycle. After this, we determined whether kisspeptin acts on the pituitary gland in vivo. Using GnRH-replaced ovariectomized hypothalamo-pituitary-disconnected ewes, we were not able to achieve any effect of kisspeptin on LH under steady-state conditions or during the period of an estrogen-induced LH surge. Finally, we collected hypophysial portal blood samples from ovariectomized ewes and measured kisspeptin levels. Low but detectable amounts of kisspeptin were found in portal plasma, but levels were similar in ovariectomized ewes that were untreated or given estrogen to elicit an LH surge. Thus, although we observed an effect of kisspeptin on LH release in vitro in some situations, similar findings were not obtained in vivo. Moreover, the low concentrations of kisspeptin in hypophysial portal blood and the lack of any change during the period of an estrogen-induced GnRH/LH surge suggest that action on the pituitary gland is not of major consequence in terms of LH release.

Effectiveness and safety of tranexamic acid administration during total knee arthroplasty

BACKGROUND

The administration of tranexamic acid (TA) is associated with a decrease in the number of red blood cell (RBC) units transfused. However, concerns about its safety have hindered its broader use.

STUDY DESIGN AND METHODS

We evaluated the effect of TA on RBC transfusion and thromboembolic complications in total knee arthroplasty. We retrospectively studied 414 patients, 215 immediately before introducing TA treatment (control group) and after, in 199 patients without history of thromboembolic diseases (TA group). In a subgroup of patients, a lower extremities contrast venography was performed.

RESULTS

Fifty-four per cent of control group patients were transfused with RBC while only 17.6% of TA group patients received RBCs. In the TA that group, those transfused received less units (2.83 vs. 1.89), showed smaller mean calculated perioperative blood loss and haemoglobin values at discharge were higher compared to control group (10.1 vs. 9.3 g/dl). Thromboembolic complications were diagnosed in 2.8% of the patients in the control group and in 1.5% in the TA group. Asymptomatic distal deep venous thrombosis was found in 54 (14.8%) of TA group patients and 54 (30.1%) of control patients. TA administration reduced the expenditure for RBC transfusion plus the cost of TA from 148.94 to 33.87 euro per patient.

CONCLUSION

Routine administration of TA during total knee arthroplasty to patients without history of thromboembolic disease is associated with a 67% reduction in RBC transfusions and, in those transfused, with a reduction in the number of units administered. TA treatment was not associated with an increase in thromboembolic complications. Transfusion costs are significantly reduced.

Prevalence and factors associated with anal lesions mediated by human papillomavirus in men with HIV/AIDS

Summary

Prevalence and risk factors for human papillomavirus-related anal lesions were evaluated in 60 men with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Patients underwent anal cytology, anuscopy under colposcopic vision and anal biopsy for detection of the lesions. The mean age was 41.9 years and the mean time of HIV infection was 6.8 years, 88.3% of them having been on highly active antiretroviral therapy for an average of 6.5 years. Homosexuals represented 43.3% and bisexuals 15.0% whereas heterosexuals comprised 41.7%. The prevalence of anal lesions detected by anuscopy under colposcopic vision, cytology and biopsy were, respectively, 35.0, 16.7 and 23.3%. Homosexuals or bisexuals accounted for 85.7% of the patients with an abnormal biopsy, the remaining 14.3% being heterosexuals (P = 0.02). The T-CD4+ lymphocyte count, HIV viral load and use of antiretrovirals did not reveal any association with anal lesions. The occurrence of anal lesions was high in the individuals with HIV/AIDS, especially in the homosexuals and bisexuals, but it also occurred in heterosexuals, justifying the screening of anal lesions of all men with the infection.

Public health response to an avian influenza A (H5N1) poultry outbreak in Suffolk, United Kingdom, in November 2007

An outbreak of highly pathogenic avian influenza (HPAI) H5N1 in a poultry farm in Suffolk, United Kingdom, in November 2007 prompted a comprehensive public health response to stop the transmission of avian influenza to humans. A total of 176 of 178 potentially exposed (99%) received oseltamivir prophylaxis. The majority of them, 169 people (96%), received the influenza vaccine during the outbreak. Thirty people who had been given post-exposure prophylaxis were actively followed up for one week. None of them developed symptoms suggestive of influenza-like illness. Serological investigation (28-day testing) of those who reported symptoms is ongoing.

Can we improve gait skills in chronic hemiplegics? A randomised control trial with gait trainer

AIM

Partial body weight support (PBWS) is an accepted treatment for hemiplegic patients. The aim of this study is to compare the efficiency of gait trainer with conventional treatment on the gait management after stroke.

METHODS

Forty chronic post-stroke hemiplegics were part of a prospective research. Inclusion criteria were: first ever stroke in a chronic stage with stabilised motor deficits; age >18 and <80 years; cognitive and communication skills to understand the treatment; absence of cardiac, psychological and orthopedic contraindications. Patients were randomised into two groups: the control group (CG) that used the Bobath method in 40 minutes sessions, 5 times a week, for 5 weeks, and the experimental group (EG) that used the gait trainer, for the same period of time and frequency. Assessment tools: Motricity Index (MI); Toulouse Motor Scale (TMS); modified Ashworth Spasticity Scale (mASS); Berg Balance Scale (BBS); Rivermead Mobility Index (RMI); Fugl-Meyer Stroke Scale (F-MSS); Functional Ambulation Category (FAC); Barthel Index (BI); 10 meters, time up and go (TUG), 6 minutes, and step tests. EG and CG did the assessments before treatment (T(0)), right after treatment (T(1)), and on follow-up, 3 months later (T(2)).

RESULTS

CG and EG were homogenous in all the variables at T(0). CG and EG showed improvement in almost all the assessment scales after treatment, although only some with relevant differences. EG showed statistically relevant improvement on T(1) and on T(2) in several of the assessment tools, whereas CG only showed statistically significant improvement after T(1) and only in some of the assessment tools.

CONCLUSIONS

Both groups of chronic hemiplegic patients improved after either PBWS with gait trainer or Bobath treatment. Only subjects undergoing PBWS with gait trainer maintained functional gain after 3 months.

Pictorial review of the many faces of bronchioloalveolar cell carcinoma

Bronchioloalveolar cell carcinoma (BAC) has a varied appearance on CT that often leads to an incorrect or delayed diagnosis. The purpose of this pictorial review is to define common CT characteristics that are specific to BAC. A retrospective review was undertaken of 20 CT scans of pathologically proven cases of BAC; tumours were categorized as focal or diffuse, single or multiple, and infiltrative or well defined. Additional radiological features noted include the density (solid, part solid, non-solid), the presence of unaffected vessels within the tumour(s), and the presence of internal air bronchograms. We illustrate cases of localized and diffuse BAC presenting as (i) solitary or multiple pulmonary nodules, with and without air bronchograms, (ii) bubble-like lucencies of pseudocavitation associated with nodules of varying density, (iii) unifocal or multifocal ground-glass opacities, (iv) crazy paving, (v) nodules and airspace opacities with unaffected vessels coursing through them and (vi) lobar or multilobar consolidation and cavitating nodules. In conclusion, BAC may present with a variety of CT appearances. However, there are typical features such as the CT-angiogram sign or air-brochochograms in solitary nodules and in the periphery of larger consolidations, persisting pure ground-glass opacities, unresolving consolidation and the combination of diffuse nodules and consolidation. These features should alert the radiologist to the diagnosis of BAC.

Effect of extending the platelet storage time on platelet utilization: predictions from a mathematical model of prophylactic platelet support

Bacterial culturing (BCU) or photochemical treatment (PCT) of platelet (PLT) concentrates may permit extending the storage time to 7 days at the cost of decreased viability of transfused PLTs. This study was aimed at predicting the impact this may have on the routine management of patients on prophylactic PLT support. The method included a mathematical model that represents the dynamics of prophylactic PLT support with standard, BCU or PCT PLTs. Data on posttransfusion PLT kinetics and the effect of PCT or storage time on PLT recovery and survival were obtained from published studies. Variables that influenced the level of PLT usage were the proportion of transfusions supplied with PLT on the last day of shelf-life, the use of PCT and the assumed degree of synergy between clinical factors of PLT consumption and either PCT or storage time. In the reference-case scenario, extending the PLT shelf-life to 7 days by BCU or PCT increased by 9 and 19%, respectively, the number of PLT transfusions per patient-year. In the worst-case scenario, these figures rose to 27 and 38%, respectively. Despite more intensive PLT usage, in most scenarios, the time that patients spent at PLT counts <10 x 10(9) L(-1) increased. Extending the shelf-life of PLT products will increase PLT usage. Such increase may be disproportionately larger for patients with complex conditions if there is a synergic interaction between storage time or PCT and clinical factors of PLT consumption, an issue that is worth further clinical research.

Mental rotation of anthropoid hands: a chronometric study

It has been shown that mental rotation of objects and human body parts is processed differently in the human brain. But what about body parts belonging to other primates? Does our brain process this information like any other object or does it instead maximize the structural similarities with our homologous body parts? We tried to answer this question by measuring the manual reaction time (MRT) of human participants discriminating the handedness of drawings representing the hands of four anthropoid primates (orangutan, chimpanzee, gorilla, and human). Twenty-four right-handed volunteers (13 males and 11 females) were instructed to judge the handedness of a hand drawing in palm view by pressing a left/right key. The orientation of hand drawings varied from 0 masculine (fingers upwards) to 90 masculine lateral (fingers pointing away from the midline), 180 masculine (fingers downwards) and 90 masculine medial (finger towards the midline). The results showed an effect of rotation angle (F(3, 69) = 19.57, P < 0.001), but not of hand identity, on MRTs. Moreover, for all hand drawings, a medial rotation elicited shorter MRTs than a lateral rotation (960 and 1169 ms, respectively, P < 0.05). This result has been previously observed for drawings of the human hand and related to biomechanical constraints of movement performance. Our findings indicate that anthropoid hands are essentially equivalent stimuli for handedness recognition. Since the task involves mentally simulating the posture and rotation of the hands, we wondered if "mirror neurons" could be involved in establishing the motor equivalence between the stimuli and the participants' own hands.

Economies of scale in blood banking: a study based on data envelopment analysis

BACKGROUND AND OBJECTIVES

Exploitation of economies of scale is often argued in favour of blood-bank consolidation into large regional centres, despite a lack of adequate empirical support. This study was aimed at testing the economies of scale hypothesis in a sample of blood centres in the USA.

MATERIALS AND METHODS

An input-orientated data envelopment analysis (DEA) was used to calculate the technical efficiency scores of blood centres, and to determine whether they were operating under increasing returns to scale (IRS), constant returns to scale (CRS) or decreasing returns to scale (DRS). Correlation between the blood-centre efficiency score and the demographic and socioeconomic characteristics of the service area was further investigated.

RESULTS

Seventy-one blood centres were included in the analysis. The scale of operations ranged from 7270 to 275,500 red blood cell (RBC) units per year. Six (8%) centres operated under CRS, 29 (55%) under IRS, and most of their technical inefficiency was scale-independent, and 26 (37%) operated under DRS, and most of their technical inefficiency was size-related. Efficiency scores were unrelated to any demographic or socioeconomic characteristics of the blood centre service area.

CONCLUSIONS

Within the size range of blood centres included in this study, expanding the level of operations beyond a certain point leads to DRS.

OryGenesDB: a database for rice reverse genetics

Insertional mutant databases containing Flanking Sequence Tags (FSTs) are becoming key resources for plant functional genomics. We have developed OryGenesDB (), a database dedicated to rice reverse genetics. Insertion mutants of rice genes are catalogued by Flanking Sequence Tag (FST) information that can be readily accessed by this database. Our database presently contains 44166 FSTs generated by most of the rice insertional mutagenesis projects. The OryGenesDB genome browser is based on the powerful Generic Genome Browser (GGB) developed in the framework of the Generic Model Organism Project (GMOD). The main interface of our web site displays search and analysis interfaces to look for insertions in any candidate gene of interest. Several starting points can be used to exhaustively retrieve the insertions positions and associated genomic information using blast, keywords or gene name search. The toolbox integrated in our database also includes an ‘anchoring’ option that allows immediate mapping and visualization of up to 50 nucleic acid sequences in the rice Genome Browser of OryGenesDB. As a first step toward plant comparative genomics, we have linked the rice and Arabidopsis whole genome using all the predicted pairs of orthologs by best BLAST mutual hit (BBMH) connectors.

Colocalization of kisspeptin and gonadotropin-releasing hormone in the ovine brain

Kisspeptin is a peptide that has been implicated in the regulation of GnRH cells in the brain. Immunohistochemical studies were undertaken to examine the distribution of kisspeptin-immunoreactive (IR) cells in the ovine diencephalon and determine the effect of ovariectomy in the ewe. We report that kisspeptin colocalizes to a high proportion of GnRH-IR cells in the preoptic area, which is a novel finding. A high level of colocalization of kisspeptin and GnRH was also seen in varicose neuronal fibers within the external, neurosecretory zone of the median eminence. Apart from the kisspeptin/GnRH cells, a population of single-labeling kisspeptin-IR cells was also observed in the preoptic area. Within the hypothalamus, kisspeptin-IR cells were found predominantly in the arcuate nucleus, and there was an increase in the number of immunohistochemically identified cell within this nucleus after ovariectomy. Kisspeptin-IR cells were also found in the periventricular nucleus of the hypothalamus, but the number observed was similar in gonad-intact and ovariectomized ewes. The colocalization of GnRH and kisspeptin within cells of the preoptic area and GnRH neurosecretory terminals of the median eminence suggests that the two peptides might be cosecreted into the hypophyseal portal blood to act on the pituitary gland. Effects of ovariectomy on the non-GnRH, Kisspeptin-IR cells of the hypothalamus suggest that kisspeptin production is negatively regulated by ovarian steroids.

Blood inventory management in the type and screen era

BACKGROUND AND OBJECTIVE

Previous models on the management of hospital blood inventories have mostly dealt with the optimization of variables related to the assigned, cross-matched inventory. Because the type and screen (T and S) procedure allows blood banks to manage surgical reserves with only unassigned inventories, it becomes necessary to gain insight into the factors that determine the efficiency of this kind of blood inventory.

STUDY DESIGN

Stochastic model that simulates the routine operation of a hospital blood bank inventory over a finite number of days was used. Factors that were analysed for their influence on outdate and shortage rates included the mean (MEAN) and variation (CVAR) in daily transfusion, the remaining shelf life of blood units shipped from the blood supplier (RSL) and the number of days between consecutive shipments (INT).

RESULTS

Outdate and shortage rates grew exponentially with CVAR, an effect that could be partially counterbalanced by increasing RSL. The variables, MEAN and INT, had little influence on the inventory, provided that blood stocks shipped from the supplier are targeted at the expected average demand for transfusion and RSL is greater than INT.

CONCLUSIONS

In hospitals that do not hold cross-matched inventories, CVAR is the major parameter in determining the blood inventory performance. Hospitals with large CVAR must be supplied with young red blood cell (RBC) units, whereas hospitals with smaller CVAR perform well with older stocks. These results advocate for using each hospital's CVAR as the leader parameter in regional optimization policies based on recycling blood units among participating hospitals.