Novel Cannabinoid Receptor 2 (CB2) Low Lipophilicity Agonists Produce Distinct cAMP and Arrestin Signalling Kinetics without Bias.

Cannabinoid Receptor 2 (CB2) is a promising target for treating inflammatory diseases. We designed derivatives of 3-carbamoyl-2-pyridone and 1,8-naphthyridin-2(1H)-one-3-carboxamide CB2-selective agonists with reduced lipophilicity. The new compounds were measured for their affinity (radioligand binding) and ability to elicit cyclic adenosine monophosphate (cAMP) signalling and ß-arrestin-2 translocation with temporal resolution (BRET-based biosensors). For the 3-carbamoyl-2-pyridone derivatives, we found that modifying the previously reported compound UOSS77 (also known as S-777469) by appending a PEG2-alcohol via a 3-carbomylcyclohexyl carboxamide (UOSS75) lowered lipophilicity, and preserved binding affinity and signalling profile. The 1,8-naphthyridin-2(1H)-one-3-carboxamide UOMM18, containing a cis configuration at the 3-carboxamide cyclohexyl and with an alcohol on the 4-position of the cyclohexyl, had lower lipophilicity but similar CB2 affinity and biological activity to previously reported compounds of this class. Relative to CP55,940, the new compounds acted as partial agonists and did not exhibit signalling bias. Interestingly, while all compounds shared similar temporal trajectories for maximal efficacy, differing temporal trajectories for potency were observed. Consequently, when applied at sub-maximal concentrations, CP55,940 tended to elicit sustained (cAMP) or increasing (arrestin) responses, whereas responses to the new compounds tended to be transient (cAMP) or sustained (arrestin). In future studies, the compounds characterised here may be useful in elucidating the consequences of differential temporal signalling profiles on CB2-mediated physiological responses.

Ion implantation of tunnel junction as a method for defining the aperture of III-nitride-based micro-light-emitting diodes.

We report on III-nitride-based micro-light-emitting diodes (µLEDs) operating at 450 nm wavelength with diameters down to 2 µm. Devices with a standard LED structure followed by a tunnel junction were grown by plasma-assisted molecular beam epitaxy. The emission size of µLEDs was defined by shallow He+ implantation of the tunnel junction region. The ion implantation process allows to create flat devices, applicable to further epitaxial regrowth. The shift of current density for the maximum external quantum efficiency as a function of µLEDs diameter was observed. This effect may be a fingerprint of the change in the external efficiency related to the lateral carrier diffusion (limited by holes) in InGaN quantum wells.

Distributed-feedback blue laser diode utilizing a tunnel junction grown by plasma-assisted molecular beam epitaxy.

In this paper, we demonstrate a novel approach utilizing tunnel junction (TJ) to realize GaN-based distributed feedback (DFB) laser diodes (LDs). Thanks to the use of the TJ the top metal contact is moved to the side of the ridge and the DFB grating is placed directly on top of the ridge. The high refractive index contrast between air and GaN, together with the high overlap of optical mode with the grating, provides a high coupling coefficient. The demonstrated DFB LD operates at λ=450.15 nm with a side mode suppression ratio higher than 35dB. The results are compared to a standard Fabry-Perot LD.

Stack of two III-nitride laser diodes interconnected by a tunnel junction.

We demonstrate a stack of two III-nitride laser diodes (LDs) interconnected by a tunnel junction grown by plasma-assisted molecular beam epitaxy. Hydrogen-free growth is used to obtain as-grown p-type conductivity essential for buried tunnel junctions (TJ). We show the impact of the design of tunnel junction. In particular, we show that, apart from the beneficial piezoelectric polarization inside the TJ, heavy doping reduces the differential resistivity even further. The device starts to lase at a wavelength of 459 nm with a slope efficiency (SE) of 0.7 W/A followed by lasing at 456 nm from the second active region doubling the total SE to 1.4 W/A. This demonstration opens new possibilities for the fabrication of stacks of ultraviolet and visible high power pulsed III-nitride LD.

Safety and effectiveness of room temperature stable recombinant factor VIIa in patients with haemophilia A or B and inhibitors: Results of a multinational, prospective, observational study.

INTRODUCTION: A room temperature stable formulation of recombinant activated factor VII (NovoSeven® ), allowing convenient storage and therefore improved treatment access, has been developed. Bioequivalence to the previous NovoSeven® was demonstrated in healthy humans, leading to European approval (2008). Although no confirmed cases of neutralising antibodies to rFVIIa in patients with haemophilia A or B have been observed with the original formulation, changes in formulation or storage condition may alter immunogenicity. AIM: SMART-7™ was designed to investigate the safety of NovoSeven® in a real-world setting in patients with haemophilia A or B with inhibitors. METHODS: Study medication was not provided by the sponsor, and treatment was at the discretion of the treating physician, in accordance with the local label. Patient baseline information was collected at enrolment. Information on safety, drug exposure and bleeding episodes was collected and FVII antibody screening was encouraged at baseline and performed at the investigator's discretion. RESULTS: Fifty-one patients were enrolled and 31 completed the study. Forty-one adverse events (AEs) were reported in 23 patients; 25 AEs in 14 patients were serious. No thromboembolic events were observed. Although four cases of reduced therapeutic response were reported, FVII antibody screening was negative. Forty-eight patients experienced 618 bleeding episodes and 93.4% of 609 evaluated bleeds were stopped by treatment. Of the 538 bleeding episodes treated with NovoSeven® monotherapy, 94.2% stopped by end of treatment. CONCLUSION: Data collected during the SMART-7™ study revealed no treatment-related safety issues and no FVII-binding antibodies for patients treated with NovoSeven® under real-world conditions.

Non-HLA gene polymorphisms in juvenile idiopathic arthritis: associations with disease outcome.

OBJECTIVE: To test the hypothesis that non-HLA single-nucleotide polymorphisms (SNPs) associated with the risk of juvenile idiopathic arthritis (JIA) are risk factors for an unfavourable disease outcome at long-term follow-up. METHODS: The Nordic JIA cohort is a prospective multicentre study cohort of patients from the Nordic countries. In all, 193 patients met the inclusion criteria of having an 8 year follow-up assessment and available DNA sample. Seventeen SNPs met the inclusion criteria of having significant associations with JIA in at least two previous independent study cohorts. Clinical endpoints were disease remission, actively inflamed joints and joints with limitation of motion (LOM), articular or extra-articular damage, and history of uveitis. RESULTS: Evidence of associations between genotypes and endpoints were found for STAT4, ADAD1-IL2-IL21, PTPN2, and VTCN1 (p = 0.003-0.05). STAT4_rs7574865 TT was associated with the presence of actively inflamed joints [odds ratio (OR) 20.6, 95% confidence interval (CI) 2.2-> 100, p = 0.003] and extra-articular damage (OR 7.9, 95% CI 1-56.6, p = 0.057). ADAD1_rs17388568 AA was associated with a lower risk of having joints with LOM (OR 0.1, 95% CI 0-0.55, p = 0.016). PTPN2_rs1893217 CC was associated with a lower risk of having joints with LOM (OR 0.2, 95% CI 0-0.99, p = 0.026), while VTCN1_rs2358820 GA was associated with uveitis (OR 3.5, 95% CI 1-12.1, p = 0.029). CONCLUSION: This exploratory study, using a prospectively followed JIA cohort, found significant associations between long-term outcome and SNPs, all previously associated with development of JIA and involved in immune regulation and signal transduction in immune cells.

[The role of chronic gastritis in past medical history with NSAID administration in patients with osteoarthrosis].

122 patients with osteoarthrosis, who have in the past medical history verified chronic gastritis (50 males and 72 females) at the age from 42 to 64 have been examined. Control group was comprised of 40 patients with osteoarthrosis without gastroduodenal zone pathology in the past medical history. For arthralgia relief patients were prescribed meloxicam (average dose--12.5 - 1.39 mg daily) or nimesulide (average dose--150 ± 14.91 mg daily). As a result of this research it was determined that administration of selective NSAID (meloxicam and nimesulide) in patients with chronic gastritis in the past medical history raised the risk of NSAID gastropathy/dyspepsia 2.9 times (P < 0.03) than in patients without associated gastroduodenal zone pathology. Atrophy of gastric mucosa is associated with higher risks (P > 0.05) of erosive gastropathy. Patients with chronic gastritis in the past medical history when taking NSAID with the purpose of gastropathy prevention are recommended to undergo gastroprotective therapy.

Types of morbidity presenting in frontline-bordering regions of Ukraine: the experience of deploying additional mobile medical units.

INTRODUCTION: On 24 February 2022, the full-scale military invasion of Russia into Ukraine has started, creating one of the largest humanitarian crises in Europe since the World War II. As of 27 July 2022 (by the time when the most of Russian advances have already occurred), more than 900 healthcare facilities in Ukraine were damaged and 127 hospitals were destroyed completely. METHODS: Mobile medical units (MMU) were deployed in the frontline-bordering areas. An MMU included a family doctor, a nurse, a social worker and a driver, and aimed to provide medical help in remote areas. 18 260 patients who received medical help in MMUs in Dnipro (Dnipro city) and Zaporizhia (Zaporizhia city and Shyroke village) oblasts from July until October 2022 were included in the study. The patients were subdivided by month of visit, area of residence and area of MMU operation. Patients' sex, age, date of visit and diagnosis were analysed. Comparison between groups was performed using analysis of variance and Pearson's χ2 tests. RESULTS: Majority of patients were females (57.4%), people aged 60+ years (42.8%) and internally displaced persons (IDPs) (54.8%). The proportion of IDPs increased from 47.4% to 62.8% over the period of study (p<0.01). The most common cause of visit to doctors was cardiovascular diseases (17.9%). The frequency of non-respiratory infections remained stable over the period of study. CONCLUSIONS: In the frontline-bordering areas of Ukraine, females, people older than 60 years and IDPs more frequently sought medical help in MMUs. Causes of morbidity in the studied population were similar to the causes of morbidity before the beginning of full-scale military invasion. Maintaining continuous access to healthcare services may be beneficial for the patient outcomes, especially in terms of cardiovascular disease.

Validity and predictive ability of the juvenile arthritis disease activity score based on CRP versus ESR in a Nordic population-based setting.

OBJECTIVE: To compare the juvenile arthritis disease activity score (JADAS) based on C reactive protein (CRP) (JADAS-CRP) with JADAS based on erythrocyte sedimentation rate (ESR) (JADAS-ESR) and to validate JADAS in a population-based setting. METHODS: The CRP and ESR values and the corresponding JADAS scores (JADAS10/27/71) were compared in a longitudinal cohort study of 389 children newly diagnosed with juvenile idiopathic arthritis (JIA) in the Nordic JIA study. The construct validity and the discriminative and predictive ability of JADAS were assessed during a median disease course of 8 years by comparing JADAS with other measures of disease activity and outcome. RESULTS: At the first study visit the correlation between JADAS27-CRP and JADAS27-ESR was r=0.99 whereas the correlation between CRP and ESR was r=0.57. Children with higher JADAS scores had an increased risk of concomitant pain, physical disability and use of disease-modifying antirheumatic drugs (DMARDs). A higher JADAS score at the first study visit also significantly predicted physical disability, damage and no remission off medication at the final study visit, and also use of DMARDs during the disease course. Sensitivity to change, demonstrated as change in JADAS score compared with the American College of Rheumatology paediatric measures of improvement criteria, mostly showed excellent classification ability. CONCLUSION: The JADAS-CRP and JADAS-ESR correlate closely, show similar test characteristics and are feasible and valid tools for assessing disease activity in JIA.

Long-term outcome in patients with juvenile dermatomyositis: a cross-sectional follow-up study.

OBJECTIVE: To evaluate a group of 53 patients with juvenile dermatomyositis (JDM), on average 13.9 years after disease onset, in order to describe the long-term disease outcome and to identify disease-related parameters associated with poor disease outcome. METHODS: Baseline information at disease onset was obtained from medical records. Disease status at follow-up was evaluated by physical examination. The Myositis Damage Index (MDI) and the Myositis Disease Damage by Visual Analogue Scale (MYODAM-VAS) were used to describe disease damage. RESULTS: Disease damage was seen in 60.4% of patients. The most common damage was cutaneous scarring (39.6%) and muscle dysfunction (34%). Calcinosis was found in 20%, lipodystrophy in 13%, and severe damage affecting more than two organ systems in 24.5% of patients. A disease duration > 4 years increased the risk of damage based on: MDI score [adjusted odds ratio (AOR) 8.3, 95% confidence interval (CI) 1.7-41.7], MYODAM-VAS score (AOR 26.2, 95% CI 3.1-223.7), and number of affected organs (AOR 16.3, 95% CI 1.1-232.4). Disease onset age ≥ 7.4 years increased the risk of more than two affected organs (AOR 15.8, 95% CI 1.9-129.4). Disease duration ≥ 4 years increased the risk of calcinosis (OR 4.8, 95% CI 1.1-20.9) and continuous muscle dysfunction (OR 4.2, 95% CI 1.1-17.3). CONCLUSION: In a long-term follow-up study, 60% of JDM patients had disease damage at a mean of 14 years after disease onset. Longer disease duration was the most important predictor of damage, calcinosis, and impaired muscle function, and higher age at disease onset predicted more organs involved at follow-up.

Developing the Cannabinoid Receptor 2 (CB2) pharmacopoeia: past, present, and future.

Cannabinoid Receptor 2 (CB2) is a G protein-coupled receptor (GPCR) with considerable, though as yet unrealised, therapeutic potential. Promising preclinical data supports the applicability of CB2 activation in autoimmune and inflammatory diseases, pain, neurodegeneration, and osteoporosis. A diverse pharmacopoeia of cannabinoid ligands is available, which has led to considerable advancements in the understanding of CB2 function and extensive preclinical evaluation. However, until recently, most CB2 ligands were highly lipophilic and as such not optimal for clinical application due to unfavourable physicochemical properties. A number of strategies have been applied to develop CB2 ligands to achieve closer to 'drug-like' properties and a few such compounds have now undergone clinical trial. We review the current state of CB2 ligand development and progress in optimising physicochemical properties, understanding advanced molecular pharmacology such as functional selectivity, and clinical evaluation of CB2-targeting compounds.

Clinical features and outcome in a Danish cohort of juvenile dermatomyositis patients.

OBJECTIVES: To assess disease characteristics and outcome in Danish juvenile dermatomyositis (JDM) patients (1977-2007). METHODS: Medical record review of hospital records identified from the National Patient Register. RESULTS: Fifty-seven JDM patients were identified. Follow-up time was 7 years (range 0.06-30). Female:male ratio was 2.5:1. Mean age at disease onset was 7 years (SD±3.7), range 1.5-16.0 years. Diagnostic delay was 0.7 years (SD±1.6), range 0.04-9 years. Mean disease duration was 3.7 years (SD±3.5), range 0.7-9 years. Thirty-nine patients (70%) were in full remission. Three patients (5%) were deceased. Disease/treatment-induced damage was present in 35 (61%) patients. Decreased pulmonary function occurred early in the disease course (median 10 months), osteoporosis and calcinosis occurred later (median 18 and 22 months). Four patients developed persistent damage within the first 6 months, four developed calcinosis within the first year. Shorter disease duration was associated with less damage (p=0.004). In a multivariate assessment analysis age >10 years at disease onset was associated with more damage (p<0.01), OR 10.96 (CI 1.6-73.6), and disease duration >4 years was associated with calcinosis (p=0.01) OR 23.2 (CI 2.6-206.2). CONCLUSIONS: We present a nationwide retrospective study of Danish JDM patients from 1977-2007. Although 70% were in remission, 61% of the patients had clinical signs of damage. Only a few patients developed damage within the first year of the disease. Longer disease duration and higher age at disease onset was correlated with more disease damage.

Influence of the Si cap layer on the SiGe islands morphology.

Transmission electron microscopy (TEM), atomic force microscopy (AFM), and EDX methods were used to study morphology and chemical composition of SiGe/Si(001) islands grown at 700 degrees C and covered at 550 degrees C and 700 degrees C by Si layers of different thickness. The samples were grown in ultra high vacuum chemical vapor deposition process (UHVCVD) controlled with in situ reflection of high-energy electron diffraction (RHEED). The islands transformed from initial pyramid and dome shapes to lens shape for 1.4 nm and 3.7 nm cap layer thickness at 550 degrees C and 700 degrees C, respectively. An increase of lateral to vertical ratio was observed during the transformation. For the higher depositing temperature the ratio was bigger and was increasing continuously with cap layer thickness. Also, with increasing Si cap layer thickness, the Ge concentration was decreasing, which was more observable for higher capping temperature.

Nonacog beta pegol in previously treated children with hemophilia B: results from an international open-label phase 3 trial.

UNLABELLED: Essentials Nonacog beta pegol is a recombinant glycoPEGylated factor IX with an extended half-life. This phase 3 trial investigated its safety/efficacy in previously treated hemophilia B boys ≤ 12 years. A 40 IU kg(-1) dose provided effective once-weekly prophylaxis and hemostasis when used to treat bleeds. Nonacog beta pegol was well tolerated in previously treated boys ≤ 12 years with hemophilia B. SUMMARY: Background Nonacog beta pegol is a recombinant glycoPEGylated factor IX with an extended half-life, developed to improve care for patients with hemophilia B. Objectives To investigate the safety, efficacy and pharmacokinetics of nonacog beta pegol for the prophylaxis and treatment of bleeds in previously treated children with hemophilia B. Patients/Methods This phase 3 trial, paradigm(™) 5, enrolled and treated 25 children (aged ≤ 12 years) with hemophilia B (FIX ≤ 2%). Patients were stratified by age (0-6 years and 7-12 years), and received once-weekly prophylaxis with 40 IU kg(-1) nonacog beta pegol for 50 exposure days. Results No patient developed inhibitors, and no safety concerns were identified. Forty-two bleeds in 15 patients were reported to have been treated; the overall success rate was 92.9%, and most bleeds (85.7%) resolved after one dose. The median annualized bleeding rates (ABRs; bleeds per patient per year) were 1.0 in the total population, 0.0 in the 0-6-year group, and 2.0 in the 7-12-year group; the estimated mean ABRs were 1.44 in the total population, 0.87 in the 0-6-year group, and 1.88 in the 7-12-year group. For 22 patients who had previously been receiving prophylaxis, the estimated mean ABR was 1.38 versus a historical ABR of 2.51. Estimated mean steady-state FIX trough levels were 0.153 IU mL(-1) (0-6 years) and 0.190 IU mL(-1) (7-12 years). Conclusion Nonacog beta pegol was well tolerated in previously treated children with hemophilia B; a 40 IU kg(-1) dose provided effective once-weekly prophylaxis and hemostasis when bleeds were treated.

Comparative incidence of de novo nonlymphoid malignancies after liver transplantation under tacrolimus using surveillance epidemiologic end result data.

BACKGROUND: An increased incidence of de novo nonlymphoid malignancies has been shown in immunocompromised patients. However, the true risk over time compared to the general population has not been determined. METHODS: One thousand consecutive patients were carefully followed for an average of 77.8+/-11.1 (range, 56.3-96.3) months after primary liver transplantation at a single center. All de novo nonlymphoid malignancies were recorded. Each malignancy was compared with a standard Occupational Cohort Mortality Analysis Program population matched for age, sex, and length of follow-up using modified life table technique and surveillance epidemiology end result (SEER) data. RESULTS: Fifty-seven patients accounted for de novo malignancies and contributed 4795.3 total person years, a mean+/-SD of 36+/-21 (median, 36; range, 6-74) months after liver transplantation. Twenty-two of these malignancies were skin malignancies including two melanomas. Oropharyngeal cancers (n=7) were found to be 7.6 times higher (P<0.05) and respiratory malignancies (n=8) were 1.7 times higher (P>0.05) compared to the SEER incidence rate. Female reproductive system malignancies including breast cancer (n=3) were 1.9 times lower (P>0.05) and genitourinary malignancies were (n=5) 1.5 times lower (P>0.05) than their matched cohorts. No differences was observed in gastrointestinal malignancies (n=5). There was a significant difference in survival of the patients after diagnosis of malignancy depending on the type of cancer. There were two Kaposi's sarcomas, two metastatic unknown primaries, one thyroid, one brain, and one ophthalmic malignancies in the series. Mortality for Kaposi's and metastatic disease of unknown primary was 100% within 5 months, while the 1-year mortality for oropharyngeal cancer was 57.1% and that for lung cancers was 62.5%. Long-term survival for skin cancer was highest: 86.4% at 3 years (P=0.015 by log-rank test). CONCLUSION: An increased incidence of de novo cancers in the chronically immunocompromised patient demands careful long-term screening protocols which will help to facilitate the diagnosis at an early stage of the disease. This is particularly true for oropharyngeal cancers where the risk is more than 7 times higher compared to SEER incidence data matched for age, sex, and length of follow-up.

Interleukin-1 receptor antagonist in neonates, children and adults, and in patients with pauci- and polyarticular onset juvenile chronic arthritis.

OBJECTIVE: The production of interleukin (IL) -1 alpha IL-1 beta and IL-1 receptor antagonist (IL-1ra) by blood mononuclear cells (MNC), as well as the corresponding serum levels of IL-1ra were examined in blood samples from umbilical cords (n = 11), children (n = 40) and adults (n = 20), and in 42 patients with juvenile chronic arthritis (JCA) of the pauci- or polyarticular onset type. RESULTS: IL-1ra serum levels were found to differ significantly between the three age groups, being higher in neonates (569 pg/ml) than in children (70 pg/ml) and adults (177 pg/ml). IL-1ra production in E. coli lipopolysacharide (LPS) stimulated-cultures of MNC was also significantly higher in neonates (median 2451 pg/ml) than in children (1526 pg/ml), but similar to that in adults (2107 pg/ml). IL-1ra levels in the sera of both subgroups of JCA patients were significantly elevated (median 257 pg/ml), but did not reflect paraclinical or clinical disease parameters. In samples of synovial fluid the IL-1ra levels tended to be fairly high, up to approximately 2 ng/ml, but they did not reflect the serum levels of IL-1ra. CONCLUSION: These findings suggests that the upregulation of IL-1ra production forms part of the immunoregulatory response in JCA patients, and that the insufficient production of IL-1ra is unlikely to contribute to the pathogenesis of JCA.

A mathematical model of aerosol holding chambers.

A mathematical model of aerosol delivery from holding chambers (spacers) was developed incorporating tidal volume (VT), chamber volume (Vch), apparatus dead space (VD), effect of valve insufficiency and other leaks, loss of aerosol by immediate impact on the chamber wall, and fallout of aerosol in the chamber with time. Four different spacers were connected via filters to a mechanical lung model, and aerosol delivery during "breathing" was determined from drug recovery from the filters. The formula correctly predicted the delivery of budesonide aerosol from the AeroChamber (Trudell Medical, London, Ontario, Canada), NebuChamber (Astra, Södirtälje, Sweden) and Nebuhaler (Astra) adapted for babies. The dose of fluticasone proportionate delivered by the Babyhaler (Glaxco Wellcome, Oxbridge, Middlesex, UK) was 80% of that predicted, probably because of incomplete priming of this spacer. Of the above-mentioned factors, initial loss of aerosol by impact on the chamber wall is most important for the efficiency of a spacer. With a VT of 195 mL, the AeroChamber and Babyhaler were emptied in two breaths, the NebuChamber in four breaths, and the Nebuhaler in six breaths. Insufficiencies of the expiratory valves were demonstrated by comparison of pressure flow curves during "inspiratory" flow with and without occluded expiratory openings. Insufficient inspiratory valves were demonstrated by comparison of "expiratory" pressure flow curves with and without occluded inspiratory openings. With children breathing through the spacers, mask pressure variations were generally on the same order as that seen with the mechanical respiratory, supporting the clinical relevance of the in vitro findings.

Orofacial pain, jaw function, and temporomandibular disorders in women with a history of juvenile chronic arthritis or persistent juvenile chronic arthritis.

OBJECTIVES: We sought to study the long-term outcome of juvenile chronic arthritis (JCA) in the temporomandibular joint (TMJ). STUDY DESIGN: Temporomandibular disorders, including TMJ involvement, were assessed in 42 women with pauciarticular or polyarticular JCA--on average 25.8 years from disease onset--and compared with those found in matched control subjects. Disease-related parameters associated with temporomandibular disorders were identified. RESULTS: The TMJ was involved in 66.7% of the patients, most severely in extended pauciarticular JCA. Temporomandibular disorders were more frequent in the patients than in the control subjects, especially in those with persistent disease. The TMJ involvement was positively correlated with disease duration and negatively correlated with jaw opening and occlusal support. Duration of active JCA and history of functional pain were identified as predictors of present TMJ involvement. CONCLUSION: In a long-term follow-up, TMJ involvement proved frequent in the studied patients and was associated with long disease duration and previous pain on jaw opening. The findings suggest that patients with JCA should undergo orofacial evaluation on a regular basis.

[A method for the cytogenetic detection of early embryos in heifers]. / Metoda pro cytogenetické vysetrení raných embryí skotu.

The objective of the study was to work out a simple and reliable method of the cytogenetic examination of bovine embryos. Whole embryos free of the zona pellucida, or parts of these embryos, were cultivated for five hours in a medium with 0.05 microgram colcemide per 1 millilitre. The embryos were hypotonized for 10 to 15 minutes in a mixture of medium and distilled water (1:2 ratio) at the temperature of 37 degrees C. Stepwise fixation was used: first in a mixture of acetic acid, methyl alcohol and water (1:4:5), followed by dropping a mixture of acetic acid and methyl alcohol (1:1) onto the embryo already on the microscope slide during microscopic control. The chromosomes were stained with a 3% solution of Giemsa dye for 10 minutes.

[Superovulation and uterine lavage in relation to subsequent conception in donor cows]. / Superovulace a výplach delohy ve vztahu k následné koncepci krav-dárkyn.

On the Slusovice co-operative farm, embryo transfer has been practised since 1984 as a method of controlled reproduction of the heifer and cow herd. The effect of superovulation, embryo recovery and administration of 500 micrograms Oestrophan Spofa upon the donors' conception rate and upon their resuming a new reproduction cycle was studied on this farm. The effect of superovulation, induced by FSH-P (Folicotropin, Spofa), was evaluated in 162 cows, out of which 121 (74.69%) got in calf after three inseminations. Fifty-nine (48.76%) of the pregnant cows got in calf after the first insemination, 38 (31.40%) after the second insemination, and 24 (19.83%) after the third insemination. Having been subjected to embryo collection and luteolysis, the donors conceived within 67.6 days, on an average, and the animals superovulated within 60 days post partum conceived within 59.11 days. The average SP of the superovulated animals was about 148 days but in the donors from which the embryos had been recovered within 60 postpartal days the SP did not exceed 110 days. Hence the earlier postpartal superovulation of cycling cows speeds up the resumption of reproduction in the donors and increases the numbers of recovered embryos. Repeated superovulation had no influence on the fertility of the cows but adequately prolonged the service period.