Frequency and characterization of the accessory heads of the biceps brachii: A multicentric cadaveric study.

PURPOSE: The biceps brachii muscle (BBM) is a large and thick muscle on the ventral portion of the upper arm. The scientific literature reports the existence of extra heads. OBJECTIVE: The present work investigated the frequency of occurrence of BBM accessory head(s) in four different Anatomy Laboratories at universities in Northeast Brazil. MATERIAL AND METHODS: Once the upper limbs with an anatomical variation of the BBM heads were identified, the accessory head was evaluated for morphometric characterization (the length, width, and thickness). RESULTS: The sample consisted of 249 upper limbs and the outcomes were 26 members with BBM accessory heads (10.44% of the total sample). Among the 26 members studied was found a single accessory head in 22 (84.62%), two accessory heads in 3 (11.54%), and three accessory heads in 1 (3.85%). BBMs with one, two, and three accessory heads were found, with different origins. The average length, width, and thickness of these accessory heads were 169.39mm, 10.25mm, and 3.39mm, respectively. CONCLUSION: The frequency of BBM accessory heads in a population of northeastern Brazil in this cadaveric study was 10.44%.

LUNCH-Lung Ultrasound for early detection of silent and apparent aspiratioN in infants and young CHildren with cerebral palsy and other developmental disabilities: study protocol of a randomized controlled trial.

BACKGROUND: Children with neurological impairment may have dysphagia and/or gastro-esophageal reflux disease (GERD), which predispose to complications affecting the airways, increasing risk for aspiration-induced acute and chronic lung disease, or secondarily malnutrition, further neurodevelopmental disturbances, stressful interactions with their caregivers and chronic pain. Only multidisciplinary clinical feeding evaluation and empirical trials are applied to provide support to the management of feeding difficulties related to dysphagia or GERD, but no standardized feeding or behavioral measure exists at any age to assess aspiration risk and support the indication to perform a videofluoroscopic swallowing study (VFSS) or a fibre-optic endoscopic examination of swallowing (FEES), in particular in newborns and infants with neurological impairments. Lung ultrasound (LUS) has been proposed as a non-invasive, radiation-free tool for the diagnosis of pulmonary conditions in infants, with high sensitivity and specificity. METHODS: A RCT will be conducted in infants aged between 0 and 6 years having, or being at risk for, cerebral palsy, or other neurodevelopmental disease that determines abnormal muscular tone or motor developmental delay assessed by a quantitative scale for infants or if there is the suspicion of GERD or dysphagia based on clinical symptoms. Infants will be allocated in one of 2 groups: 1) LUS-monitored management (LUS-m); 2) Standard care management (SC-m) and after baseline assessment (T0), both groups will undergo an experimental 6-months follow-up. In the first 3 months, infants will be evaluated a minimum of 1 time per month, in-hospital, for a total of 3 LUS-monitored meal evaluations. Primary and secondary endpoint measures will be collected at 3 and 6 months. DISCUSSION: This paper describes the study protocol consisting of a RCT with two main objectives: (1) to evaluate the benefits of the use of LUS for monitoring silent and apparent aspiration in the management of dysphagia and its impact on pulmonary illness and growth and (2) to investigate the impact of the LUS management on blood sample and bone metabolism, pain and interaction with caregivers. TRIAL REGISTRATION: Trial registration date 02/05/2020; ClinicalTrials.gov Identifier: NCT04253951 .

Palbociclib as single agent or in combination with the endocrine therapy received before disease progression for estrogen receptor-positive, HER2-negative metastatic breast cancer: TREnd trial.

Background: The activity of palbociclib as a single agent in advanced breast cancer has not been extensively studied, with the only available clinical data limited to heavily pretreated patients. Preclinical data suggests palbociclib may partially reverse endocrine resistance, though this hypothesis has not been evaluated in previous clinical studies. This phase II, open-label, multicenter study examined the activity of palbociclib monotherapy, as well as palbociclib given in combination with the same endocrine therapy (ET) that was received prior to disease progression, in postmenopausal women with moderately pretreated, estrogen receptor-positive, HER2 negative advanced breast cancer. Patients and methods: Eligible women with advanced disease which had progressed on one or two prior ETs were randomized 1 : 1 to receive either palbociclib alone, or palbociclib in combination with the ET as previously received. Primary end point was clinical benefit rate (CBR); secondary end points included progression-free survival (PFS). Results: Between October 2012 and July 2016, a total of 115 patients were randomized. The CBR was 54% [95% confidence interval (CI): 41.5-63.7] for combination therapy, and 60% (95% CI: 47.8-72.9) for monotherapy. Median PFS was 10.8 months (95% CI: 5.6-12.7) for combination therapy, and 6.5 months (95% CI: 5.4-8.5) for monotherapy [hazard ratio (HR) 0.69; 95% CI: 0.4-1.1, exploratory P-value = 0.12]. Exploratory analyses revealed the PFS advantage for combination therapy was seen in the subgroup of patients who received prior ET for >6 months (HR 0.53; 95% CI: 0.3-0.9, exploratory P-value = 0.02), but not in those who received prior ET for ≤6 months. Conclusion: Palbociclib has clinical activity as a single agent in women with moderately pretreated, oestrogen receptor-positive, HER2-negative advanced breast cancer. Palbociclib may have potential to reverse endocrine resistance in patients with a history of previous durable response to ET. Clinical trial information: NCT02549430.

Protective effect of Propolfenol® on induced oxidative stress in human spermatozoa.

The propolis extract was shown to possess the capacity to protect sperm membrane from the deleterious action of oxidative attack. Oxidative stress can induce propagation of a lipid peroxidation (LPO) chain reaction because spermatozoa contain high concentration of unsaturated fatty acids. This study aimed at evaluating in vitro the possible toxicity and/or the antioxidant properties of Propolfenol® in ejaculated human spermatozoa. A colorimetric assay determined the total flavonoid content by spectrophotometry and a high-performance liquid chromatography-diode array detection analysis the quantity of galangin, pinocembrin and caffeic acid phenylethilic ester (CAPE). Sperm parameters such as motility, vitality and DNA integrity were assessed utilising optical microscopy. The antioxidant properties Propolfenol® against LPO induced by tert-Butyl Hydroperoxide were evaluated using the C11-BODIPY581/591 probe. Chemical analysis of Propolfenol® revealed low quantities of galangin, pinocembrin and CAPE; cyclic voltammetry experiments showed that Propolfenol® may exert an antioxidant activity. A protective action of Propolfenol® (20 and 100 µg/ml) on induced LPO in human spermatozoa was detected. Propolfenol® may be proposed as the supplement in media for sperm preparation techniques or cryopreservation to counteract the increased presence of reactive oxygen species generated by these methods.

Sperm with fibrous sheath dysplasia and anomalies in head-neck junction: focus on centriole and centrin 1.

Spermatozoa with a rare combination of two monomorphic sperm defects, dysplasia of the fibrous sheath (DFS) and alterations in head-mid-piece junction were analysed. The main focus was to explore the status of the centriole, a key organisation during fertilisation, using the centrin 1, a calcium-binding protein linked to this structure. The sperm quality was examined by light, scanning and transmission electron microscopy (SEM, TEM); immunocytochemistry was performed for tubulin, A-kinase anchor protein 4 (AKAP4) and centrin 1. Spermatozoa showed DFS defect associated with anomalies in head-tail attachment detected by SEM and TEM. Immunolocalisation of tubulin, AKAP4 and centrin 1 confirmed these alterations. Centrin 1 was visible in 67% of spermatozoa (in only 13% centrin localised in a normal position); in the majority of sperm centrin 1's location was altered, sometimes bent; often four spots, indicating the presence of two implantation fossae, were detected. At the centriolar level, immunoreactive fragments, frequently invading the entire short and thick tail, were observed. Centrin 1 is an essential component of the spermatozoa connecting piece and plays a role in centrosome dynamics during sperm morphogenesis and in zygotes and early embryos during spindle assembly. It is important to shed light on these rare conditions in order to better manage the patients during assisted reproductive technology.

Immunolocalisation of ghrelin and obestatin in human testis, seminal vesicles, prostate and spermatozoa.

The role of ghrelin and obestatin in male reproduction has not completely been clarified. We explored ghrelin and obestatin localisation in the male reproductive system. Polyclonal antibodies anti-ghrelin and anti-obestatin were used to detect the expression of these hormones in human testis, prostate and seminal vesicles by immunocytochemistry, while in ejaculated and swim up selected spermatozoa by immunofluorescence. Sertoli cells were positive for both peptides and Leydig cells for ghrelin; germ cells were negative for both hormones. Mild signals for ghrelin and obestatin were observed in rete testis; efferent ductules were the most immune reactive region for both peptides. Epididymis was moderately positive for ghrelin; vas deferens and seminal vesicles showed intense obestatin and moderate ghrelin labelling; prostate tissue expressed obestatin alone. Ejaculated and selected spermatozoa were positive for both peptides in different head and tail regions. This study confirms ghrelin localisation in Leydig and Sertoli cells; the finding that ghrelin is expressed in rete testis, epididymis, vas deferens and seminal vesicles is novel, as well as the localisation of obestatin in almost all tracts of the male reproductive system. This research could offer insights for stimulating other studies, particularly on the role of obestatin in sperm physiology, which is still obscure.

In vitro effect of gold and silver nanoparticles on human spermatozoa.

The cytotoxicity of Au/Ag nanoparticles (NPs) on human spermatozoa was investigated in vitro. Semen from donors were incubated (37 °C, 60'-120') with 30, 60, 125, 250 and 500 µM Au/Ag-NPs. Sperm motility was evaluated following WHO guidelines; sperm viability was assessed with eosin Y test. Au-NPs were characterised and localised with field emission gun-based scanning transmission electron microscope/energy dispersive spectroscopy and transmission electron microscopy. Both tested NPs exerted a significant dose-dependent effect on motility and viability of human spermatozoa (P < 0.001). Ag-NPs seem to show a slightly elevated toxicity although not significant (P > 0.05). Au-NPs were localised in spermatozoa, whereas Ag-NPs were undetectable. In conclusion, Au-NPs and Ag-NPs do not appear to be harmful for human spermatozoa up to high concentrations (250-500 µM) that are probably difficult to reach in vivo. It is mandatory to explore the genotoxic effect of NPs in germ cells.

Alterations of the FSH and LH receptor genes and evaluation of sperm ultrastructure in men with idiopathic hypergonadotropic hypogonadism.

PURPOSE: Gonadotropins, interacting with their gonadal receptors, play a key role in sexual development, reproductive functions and metabolism. In this study we performed the genetic analysis of FSHR and LHR and semen investigation in 14 infertile men with normal level of T and elevated levels of FSH and/or LH in the absence of other causes of infertility. METHODS: Sperm parameters were analysed following WHO (2010) guidelines and sperm morphology by Transmission Electron Microscopy (TEM) analysis mathematically elaborated. FSHR and LHR gene mutations have been searched by PCR technique, followed by DHPLC analysis and direct sequencing. RESULTS: In FSHR, we found no difference in the frequency between Ala or Thr at position 307, Ser was at codon 680 in all subjects. Three patients had an heterozygous mutation at codon 419. Three intronic polymorphisms (rs2091787, rs6708637, rs1922464) were significantly found compared to controls; the single allele frequency and the odds ratio were calculated. Two new variants: the Cys338Arg and the Gln123Glu were detected in two different patients. Regarding LHR, three patients were heterozygous for the known variant Glu354Lys and two for Ile374Thr. Intronic polymorphisms were not identified. A new variant, the Val144Ile was found. By the routine semen analysis, variable seminal conditions in this group of patients was observed, on the contrary TEM data mathematically elaborated showed a homogeneous decrease in fertility index and increase in sperm pathologies such as apoptosis and immaturity. CONCLUSIONS: The obtained results suggest that a deeper examination of spermatozoa, achieved by the use of more powerful tools such as TEM or molecular analysis, are advisable in patients with hypergonadotropic hypogonadism.

A comprehensive study to reveal the potential of a more sustainable ultra-high performance enantioselective reversed-phase chromatography on Pirkle-type stationary phase, with Whelk-O1 as a case study.

In this study, we aimed to make enantioselective chromatography more sustainable, more sensitive, and compatible with aqueous formulations analysis and ESI-MS. To achieve this, we examined the effects of transitioning from normal-phase chromatography (which uses hydrocarbon-based solvents) to reversed-phase chromatography (using mobile phases based on water) using broad-spectrum Whelk-O1 columns as a critical study. For the first time, we holistically compared the thermodynamics and kinetics of the two elution modes in order to answer the question of whether same-column chemistry can effectively separate the compounds even in reversed-phase mode and found, unexpectedly, that reversed-phase chromatography using acetonitrile as the organic modifier was competitive from a kinetic standpoint. We also evaluated the effectiveness of three organic modifiers simultaneously on a sample of 11 molecules already resolved in NP conditions with different resolutions and achieved a resolution value of 1.5 for 91% and a resolution value of 2 for 82% of cases. Finally, we separated three racemates (within a k factor of 9) using only 480 µL of solvent per chromatographic run on a millibore column of 1 mm I.D., demonstrating that our approach allows for greener chromatographic separations.

Correlation between physical activity, nutritional intake, and osteoporosis in postmenopausal women: a preliminary evaluation.

OBJECTIVE: Osteoporosis is a chronic metabolic syndrome associated with debilitating consequences that represents one of the major non-communicable diseases and the most common bone illness that affects both men and women. This observational study evaluates the amount of physical activity and the nutritional intake in a group of postmenopausal women who have a sedentary job. PATIENTS AND METHODS: All subjects underwent a medical evaluation, a body impedance analysis to evaluate body composition (fat mass, fat-free mass, and body cell mass), and a dual-energy X-ray absorptiometry to analyze bone mineral density. Additionally, a 3-day food record questionnaire and the International Physical Activity Questionnaire were administered respectively to evaluate patients' foods and beverages assumptions and the participants' Physical Activity levels. RESULTS: The study showed that most of the patients had a moderate activity level and inadequate calcium and vitamin D assumption compared to guidelines. CONCLUSIONS: The onset of osteoporosis seemed to be reduced at higher levels of leisure time, domestic, and transport activities, even in subjects who have a sedentary job and insufficient assumption of micronutrients.

Effect of a bacterial lipopolysaccharide treatment on rabbit testis and ejaculated sperm.

In a previous study, we reported the short- and long-term effects of bacterial lipopolysaccharide (LPS)-induced inflammation on rabbit sperm quality. This study was aimed at exploring the spermatogenesis of the rabbit model focussing on the possible damages occurring to the testis and ejaculated sperm. Twenty New Zealand White rabbit bucks were divided into two groups. One group was inoculated intra-peritoneally with LPS, the other group, considered as control, was treated under the same conditions with saline only. Semen samples were collected before LPS injection, the 7th, 14th, 21st, 30th, 45th, 60th and 90th day after LPS treatment. Semen parameters were evaluated following international guidelines. The kinetic characteristics of ejaculated sperm were analysed using a computer-assisted sperm analyzer and the ultrastructural characteristics were explored by transmission electron microscopy (TEM). On the 7th, 14th and 30th day, testis from treated rabbits and controls were obtained. Testis samples were analysed by light microscopy and TEM. The induced LPS lesions in the testis became evident the 7th day after treatment, with a decrease in germinal cells and with an increase in structurally altered Sertoli cells; normal spermatogenesis was restored on the 30th day. The testicular damages observed on day 7 were probably responsible for the reduction in sperm concentration and motility and the ultrastructural alterations that were detected in the ejaculated sperm on the 14th through the 30th days after treatment. In conclusion, rabbit buck treated with LPS could be a useful model for studying the effect of an induced systemic inflammation on spermatogenesis.

Terrestrial gamma-ray flashes as powerful particle accelerators.

Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and γ rays lasting a few milliseconds or less. We present in this Letter new TGF timing and spectral data based on the observations of the Italian Space Agency AGILE satellite. We determine that the TGF emission above 10 MeV has a significant power-law spectral component reaching energies up to 100 MeV. These results challenge TGF theoretical models based on runaway electron acceleration. The TGF discharge electric field accelerates particles over the large distances for which maximal voltages of hundreds of megavolts can be established. The combination of huge potentials and large electric fields in TGFs can efficiently accelerate particles in large numbers, and we reconsider here the photon spectrum and the neutron production by photonuclear reactions in the atmosphere.

The use of recombinant human activated protein C (drotrecogin alpha) in solid organ transplant recipients: case series and review of the literature.

Septic shock occurs frequently in solid organ transplant (SOT) recipients. Standard therapy includes fluid resuscitation, the administration of antimicrobials, and source control of the infection. Adjunctive therapy with recombinant human activated protein C (rhaPC), also called drotrecogin alpha, is another treatment that is used in patients but has not been studied in SOT patients. Concerns regarding the use of this drug in this patient population include the risk of bleeding and the potential to adversely affect graft survival. Here we report the largest case series of SOT recipients with septic shock who received rhaPC. This was a retrospective chart review that looked at the impact of this drug in the SOT population. In this single-center study, we identified 17 patients with a SOT and septic shock who received rhaPC. Six of the patients underwent kidney transplants, 5 received lung transplants, 4 received cadaveric liver transplants, and 2 received combined kidney/pancreas transplants. The average APACHE II score was 26.6 ± 5.5; all patients were undergoing mechanical ventilation and receiving vasopressors at the time of rhaPC administration. Overall mortality in the group was 23.5% (4/17) at 28 days post infusion. All of the deaths were due to complications of septic shock. Allograft survival was present in 13/17 (76.5%) of the patients at 28 days. Bleeding occurred in 17.6% of patients (3/17). The use of rhaPC appears to be associated with a favorable effect on mortality, with the potential for increased risk of bleeding. Clinicians must balance this risk with the potential benefit of this drug until further research can be conducted.

Gamma-ray localization of terrestrial gamma-ray flashes.

Terrestrial gamma-ray flashes (TGFs) are very short bursts of high-energy photons and electrons originating in Earth's atmosphere. We present here a localization study of TGFs carried out at gamma-ray energies above 20 MeV based on an innovative event selection method. We use the AGILE satellite Silicon Tracker data that for the first time have been correlated with TGFs detected by the AGILE Mini-Calorimeter. We detect 8 TGFs with gamma-ray photons of energies above 20 MeV localized by the AGILE gamma-ray imager with an accuracy of ∼5-10° at 50 MeV. Remarkably, all TGF-associated gamma rays are compatible with a terrestrial production site closer to the subsatellite point than 400 km. Considering that our gamma rays reach the AGILE satellite at 540 km altitude with limited scattering or attenuation, our measurements provide the first precise direct localization of TGFs from space.

Semen characteristics and inflammatory mediators in infertile men with different clinical diagnoses.

This study was aimed at investigating whether semen characteristics in different clinical diagnoses of infertility are associated with PMN elastase, IL-6, IL-8, IL-1beta and TNFalpha levels detected in seminal plasma. Sixty-eight patients were divided into groups according to their clinical diagnosis: idiopathic infertility (group I), varicocele with infections (group II), varicocele (group III), infections (group IV), controls (group V). Physical examination and scrotal Eco-color Doppler was used to detect the varicocele. Patients with positive bacteriological semen analysis were considered as having an infection of the male reproductive tract. Samples were examined by light microscopy and transmission electron microscopy (TEM). TEM data were quantified with a mathematical formula furnishing a fertility index and the percentage of sperm apoptosis, immaturity and necrosis. PMN elastase/alpha1-PI complex levels were determined by ELISA and IL-6, IL-8, IL-1beta, TNFalpha by Bio-Plex Cytokine assay. Sperm concentration (I-II: p < 0.005; III-IV: p < 0.0001), motility (I-IV: p < 0.0001) and the fertility index (I: p < 0.005; II-IV: p < 0.0001) were significantly lower in the groups vs. controls, whereas sperm pathologies, except for apoptosis, were significantly higher in group I and apoptosis and necrosis were higher in group III. An increase in immaturity (p < 0.005) with a decrease in necrosis (p < 0.005) were observed in group III vs. group IV. Significantly higher levels of inflammatory mediators were detected in groups III and IV vs. controls. Despite a broad relationship among different inflammatory mediators, no correlation was found among them and the semen parameters, including indices from TEM analysis. In conclusion, patients with idiopathic infertility showed altered semen quality and normal levels of inflammatory mediators. Genitourinary infection and varicocele induced an inflammatory effect which could play a detrimental role in spermatogenesis, revealed by a decrease in sperm motility and the fertility index, concomitant with an increase in immaturity mainly in varicocele and necrosis in infection.

TEM and FISH studies in sperm from men of couples with recurrent pregnancy loss.

The role of the male partner in recurrent pregnancy loss (RPL) is not clear. In this study, semen characteristics of 22 men whose partners had experienced RPL were examined by light microscopy. Sperm morphology was analysed by transmission electron microscopy (TEM) and the data were mathematically elaborated to obtain numerical indices expressing the status of an ejaculate: the fertility index and the percentage of apoptosis, necrosis and immaturity. Sperm apoptosis and necrosis were also evaluated by annexin V/propidium iodide assay. To explore the status of meiotic segregation, fluorescence in situ hybridisation (FISH) with probes for chromosomes 18, X and Y, was applied directly on sperm nuclei. Sperm characteristics from a group of men of proven fertility were used as controls. Among the considered sperm characteristics, apoptosis (P < 0.01), 1818YY diploidy (P < 0.05) and 18YY disomy (P < 0.01) scores were significantly higher in men with RPL compared with controls. Our study showed that some patients with normal semen parameters can present a slight increase in aneuploidy compared with controls, indicating a possible involvement of sperm in some cases of RPL. Chromosomal FISH analysis and chromatin tests of sperm could be included in RPL work-ups when no other cause has been detected.

Sperm ultrastructure and meiotic segregation in a group of patients with chronic hepatitis B and C.

Little is known about the effect of chronic hepatitis B and hepatitis C on sperm quality. In this study, we analysed sperm quality from selected patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. Semen samples were examined by light and transmission electron microscopy (TEM). TEM data were elaborated with a mathematical formula able to indicate a fertility index and the presence of the three main sperm pathologies: apoptosis, immaturity and necrosis. Meiotic chromosome segregation was investigated by fluorescence in situ hybridisation carried out on sperm nuclei, using probes for chromosomes 18, X and Y. Despite normal sperm concentration, we observed reduced motility. TEM analysis highlighted that 35.7% of patients showed generally good semen quality. However, significantly higher values of apoptosis and necrosis, compared with controls, were observed, demonstrating spermatogenetic alterations. Regarding meiotic segregation, we found an incidence of disomies similar to that observed in control samples, whereas diploidy resulted higher in HCV patients, without reaching statistical significance. In conclusion, sperm quality in the studied group was not impaired; however, apoptosis and necrosis resulted out of normal range and the fertility index was significantly lower in HCV- and HBV-infected patients versus controls.

Sperm ultrastructure and meiotic segregation in a group of patients with chronic hepatitis B and C.

Little is known about the effect of chronic hepatitis B and hepatitis C on sperm quality. In this study we analysed sperm quality from selected patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. Semen samples were examined by light and transmission electron microscopy (TEM). TEM data were elaborated with a mathematical formula able to indicate a fertility index and the presence of the three main sperm pathologies: apoptosis, immaturity and necrosis. Meiotic chromosome segregation was investigated by fluorescence in situ hybridisation carried out on sperm nuclei, using probes for chromosomes 18, X and Y. Despite normal sperm concentration, we observed reduced motility. TEM analysis highlighted that 35.7% of patients showed generally good semen quality. However, significantly higher values of apoptosis and necrosis, compared with controls, were observed, demonstrating spermatogenetic alterations. Regarding meiotic segregation, we found an incidence of disomies similar to that observed in control samples, whereas diploidy resulted higher in HCV patients, without reaching statistical significance. In conclusion, sperm quality in the studied group was not impaired, however, apoptosis and necrosis resulted out of normal range and the fertility index was significantly lower in HCV and HBV infected patients versus controls.

Distribution of alpha-, gamma (+beta)- and delta-tocopherol in the seminal plasma, spermatozoa and seminal vesicles of rabbit.

Dietary vitamin E supplementation plays a key role in animal reproduction by protecting germ cells from oxidative damage. Recently, alpha-tocopherol homologues (namely, beta-, gamma- and delta-tocopherol) have been the object of increasing research because of their peculiar nonantioxidant properties. We found that these tocol-derived compounds are not homogeneously distributed among semen components. Alpha-T was the major vitamin E homologue found in all semen fractions. Half of the total gamma (+beta)-T was found in germ cells, while more than 50% of total delta-T was preferentially accumulated in seminal plasma. The concentration of various tocol-derived compounds depended on their relative amounts in diet and the competition for saturable enzymes implicated in their metabolism. A higher concentration of delta-T in seminal plasma may be related to its more polar nature. However, the biological function of this compound in semen remains to be cleared. To our knowledge, this is the first study aimed at identifying alpha-tocopherol homologues in rabbit semen fractions.

Count-rate analysis from clinical scans in PET with LSO detectors.

The purpose of optimising the acquisition parameters in positron emission tomography is to improve the quality of the diagnostic images. Optimisation can be done by maximising the noise equivalent count rate (NECR) that in turn depends on the coincidence rate. For each bed position the scanner records coincidences and singles rates. For each patient, the true, random and scattered coincidences as functions of the single count rate(s) are determined by fitting the NEMA (National Electrical Manufacturers Association) 70 cm phantom count rate curves to measured clinical points. This enables analytical calculation of the personalised PNECR [pseudo NECR(s)] curve, linked to the NECR curve. For central bed positions, missing activity of approximately 70% is estimated to get maximum PNECR (PNECR(max)), but the improvement in terms of signal-toz-noise ratio would be approximately 15%. The correlation between patient weight and PNECR(max) is also estimated to determine the optimal scan duration of a single bed position as a function of patient weight at the same PNEC. Normalising the counts at PNECR(max) for the 70 kg patient, the bed duration for a 90 kg patient should be 230 s, which is approximately 30% longer. Although the analysis indicates that the fast scanner electronics allow using higher administered activities, this would involve poor improvement in terms of NECR. Instead, attending to higher bed duration for heavier patients may be more useful.