Effects of acute femoral head ischemia on the growth plate and metaphysis in a piglet model of Legg-Calvé-Perthes disease.

OBJECTIVE: To determine the effects of acute (≤7 days) femoral head ischemia on the proximal femoral growth plate and metaphysis in a piglet model of Legg-Calvé-Perthes disease (LCPD). We hypothesized that qualitative and quantitative histological assessment would identify effects of ischemia on endochondral ossification. DESIGN: Unilateral femoral head ischemia was surgically induced in piglets, and femurs were collected for histological assessment at 2 (n = 7) or 7 (n = 5) days post-ischemia. Samples were assessed qualitatively, and histomorphometry of the growth plate zones and primary spongiosa was performed. In a subset of samples at 7 days, hypertrophic chondrocytes were quantitatively assessed and immunohistochemistry for TGFß1 and Indian hedgehog was performed. RESULTS: By 2 days post-ischemia, there was significant thinning of the proliferative and hypertrophic zones, by 63 µm (95% CI -103, -22) and -19 µm (95% CI -33, -5), respectively. This thinning persisted at 7 days post-ischemia. Likewise, at 7 days post-ischemia, the primary spongiosa was thinned to absent by an average of 311 µm (95% CI -542, -82) in all ischemic samples. TGFß1 expression was increased in the hypertrophic zone at 7 days post-ischemia. CONCLUSIONS: Alterations to the growth plate zones and metaphysis occurred by 2 days post-ischemia and persisted at 7 days post-ischemia. Our findings suggest that endochondral ossification may be disrupted at an earlier time point than previously reported and that growth disruption may occur in the piglet model as occurs in some children with LCPD.

Quantitative T2 and T1ρ mapping are sensitive to ischemic injury to the epiphyseal cartilage in an in vivo piglet model of Legg-Calvé-Perthes disease.

OBJECTIVE: To determine if the quantitative MRI techniques T2 and T1ρ mapping are sensitive to ischemic injury to epiphyseal cartilage in vivo in a piglet model of Legg-Calvé-Perthes disease using a clinical 3T MRI scanner. We hypothesized that T2 and T1ρ relaxation times would be increased in the epiphyseal cartilage of operated vs contralateral-control femoral heads 1 week following onset of ischemia. DESIGN: Unilateral femoral head ischemia was surgically induced in eight piglets. Piglets were imaged 1 week post-operatively in vivo at 3T MRI using a magnetization-prepared 3D fast spin echo sequence for T2 and T1ρ mapping and a 3D gradient echo sequence for cartilage segmentation. Ischemia was confirmed in all piglets using gadolinium contrast-enhanced MRI. Median T2 and T1ρ relaxation times were measured in the epiphyseal cartilage of the ischemic and control femoral heads and compared using paired t-tests. Histological assessment was performed on a subset of five piglets. RESULTS: T2 and T1ρ relaxation times were significantly increased in the epiphyseal cartilage of the operated vs control femoral heads (ΔT2 = 11.9 ± 3.7 ms, 95% CI = [8.8, 15.0] ms, P < 0.0001; ΔT1ρ = 12.8 ± 4.1 ms, 95% CI = [9.4, 16.2] ms, P < 0.0001). Histological assessment identified chondronecrosis in the hypertrophic and deep proliferative zones within ischemic epiphyseal cartilage. CONCLUSIONS: T2 and T1ρ mapping are sensitive to ischemic injury to the epiphyseal cartilage in vivo at clinical 3T MRI. These techniques may be clinically useful to assess injury and repair to the epiphyseal cartilage to better stage the extent of ischemic damage in Legg-Calvé-Perthes disease.

The association between collagen and bone biomarkers and radiographic osteoarthritis in the distal tarsal joints of horses.

BACKGROUND: Osteoarthritis (OA) of the distal intertarsal (DIT) and tarsometatarsal (TMT) joints occurs commonly. Synovial fluid (SF) biomarkers of collagen and bone turnover have potential clinical value. OBJECTIVES: To measure SF biomarker concentrations from DIT and TMT joints in adult horses and determine if they correlate with radiographic OA severity and are higher in joints with radiographic OA compared to controls. STUDY DESIGN: Cross-sectional. METHODS: Radiographic OA of DIT and TMT joints was evaluated from adult horses (5-35 years old). Overall radiographic scores divided horses into those with mild or moderate radiographic OA (16 joints from 9 horses) or controls (13 joints from 9 horses). Direct biomarkers of OA (Carboxypropeptide of type II collagen = CPII, carboxy-neoepitope of type II collagen exposed after collagenase-cleavage = C2C, Bone alkaline phosphatase = BAP and Chondroitin sulfate epitope = CS846) were measured via ELISA and CPII/C2C was calculated. Biomarkers were correlated with radiographic findings and concentrations from those with radiographic OA to control joints and were compared. RESULTS: Concentrations of CPII (R = 0.84, P<0.001), C2C (R = 0.69, P<0.001) and BAP (R = 0.41, P = 0.03) as well as CPII/C2C (R = 0.69, P<0.001) values positively correlated with overall radiographic scores. Adjusted means ± s.d., after controlling for age, for CPII (P<0.001), C2C (P<0.001), CPII/C2C (P = 0.004) and BAP (P = 0.05) were significantly higher in DIT and TMT joints with radiographic OA (CPII: 2174.45 ± 1064.01; C2C: 233.52 ± 51.187; CPII/C2C: 9.01 ± 4.09; BAP: 21.98 ± 15.34) compared to controls (CPII: 594.53 ± 463.05; C2C: 153.12 ± 48.95; CPII/C2C: 3.96 ± 2.38; BAP: 12.76 ± 3.61). CPII (P<0.001), C2C (P = 0.001) and CPII/C2C (P = 0.001) were significantly higher with moderate radiographic OA (CPII: 2444.61 ± 772.78; C2C: 248.90 ± 44.94; CPII/C2C: 9.47 ± 2.97) compared to controls (CPII: 658.38 ± 417.36; C2C: 156.49 ± 47.61; CPII/C2C: 4.15 ± 2.04), with CPII also showing significantly higher concentrations (P = 0.04) with mild radiographic OA compared (1515.00 ± 584.95) to controls (658.38 ± 417.36). There were no differences in CS846 concentrations between radiographic OA and control joints. Age positively correlated with CPII (R = 0.48, P = 0.01) and C2C (R = 0.44, P = 0.02) concentrations. MAIN LIMITATIONS: Radiographic OA was assessed, not clinical lameness. Controls were not age-matched to those with spontaneous radiographic OA. CONCLUSIONS: There is an association between collagen (CPII, C2C and CPII/C2C) and bone (BAP) biomarkers and radiographic OA in the distal tarsal joints of horses.

Early experience on a modern, thin cochlear implant family. A retrospective, international multicenter study.

RATIONALE: Cochlear implantation is the most effective method of rehabilitation for patients with severe to profound sensorineural hearing loss. Binaural hearing forms the basis of the development of hearing-associated cortical networks in infants and toddlers, but simultaneous bilateral implantation is often postponed due to the demands of classical surgical methods, which are associated with large incisions and a deep bony well. OBJECTIVE: The authors report on the use of a modern, thin implant type and the possibilities it provided to simplify the surgical technique. METHODS AND RESULTS: Recent models of the Cochlear™ Nucleus® implant family were studied in an international retrospective multi-center study: 6 otolaryngologists in 5 centers shared their experiences on 73 consecutively implanted, thin implants. The surgical incision could be made shorter than before and only shallow bony wells or none at all were created in 4 out of 5 centers. No complications occurred. DISCUSSION: This study underlines that implants with thin electronics capsules enable a simplified, fast and safe implantation procedure that allows simultaneous bilateral cochlear implantation.

Osteochondrosis prevalence and severity at 12 and 24 weeks of age in commercial pigs with and without organic-complexed trace mineral supplementation.

Maternal and progeny diets supplemented with 2 sources of trace mineral (TM) were evaluated for effects on the size and severity of osteochondrosis (OC) lesions in progeny produced by 64 Landrace × Large White sows. At breeding, sows were randomly assigned to maternal diets (gestation and lactation) consisting 1 of 2 TM treatments. One treatment consisted of inorganic TM (ITM) with ZnO, MnSO, and CuSO at concentrations to provide 150, 50, and 16.5 mg/kg diet of Zn, Mn, and Cu, respectively. The other treatment consisted of the same ITM concentrations plus an additional 50, 20, and 10 mg/kg diet of Zn, Mn, and Cu, respectively, supplied by a blend of AA-complexed TM (CTM) using Availa Sow. Within maternal dietary treatment groups, selected progeny ( = 280) were fed either ITM- or CTM-supplemented diets. The humerus and femur (1 each) from progeny euthanized at 12 ( = 80) or 24 wk ( = 200) were collected for microscopic (12 wk) or gross (24 wk) assessment of OC lesions. Microscopic OC lesions were present in all pigs at 12 wk. Dietary treatments had limited effects on OC prevalence or severity. A maternal × progeny diet interaction ( = 0.044) revealed femoral OC latens lesions that were approximately twice the size in progeny fed CTM that were produced by sows fed CTM compared with those found in pigs in the other 3 dietary treatment groups. At 24 wk, the sum of gross OC scores at predilection sites of the thoracic (elbow joint) and pelvic (stifle and hock joints) limbs remained similar among treatments, despite greater ( = 0.004) gross OC scores of the medial femoral condyle in progeny from sows fed CTM diets than in progeny from sows fed ITM diets, regardless of progeny diet. Progeny produced by sows fed CTM vs. ITM had increased ADG (0.71 vs. 0.68 ± 0.01 kg/d), regardless of the diet fed to progeny during the growth phases. Covariant analysis using ADG did not alter inferences about maternal or progeny diet effects on OC responses. Although 100% of progeny at 12 wk had histologically apparent OC lesions, only 3 of the 200 pigs examined at 24 wk had gross lesions of sufficient severity to potentially result in clinically apparent disease. Therefore, although some results imply that maternal and progeny CTM diets increased the size (12 wk) and severity (24 wk) of OC in 1 site (the femur), on the whole animal level, no evidence of lameness was noted.

A novel non-opioid binding site for endomorphin-1.

Endomorphins are natural amidated opioid tetrapeptides with the following structure: Tyr-Pro-Trp-Phe-NH2 (endomorphin-1), and Tyr-Pro-Phe-Phe-NH2 (endomorphin-2). Endomorphins interact selectively with the µ-opioid or MOP receptors and exhibit nanomolar or sub-nanomolar receptor binding affinities, therefore they suggested to be endogenous agonists for the µ-opioid receptors. Endomorphins mediate a number of characteristic opioid effects, such as antinociception, however there are several physiological functions in which endomorphins appear to act in a fashion that does not involve binding to and activation of the µ-opioid receptor. Our recent data indicate that a radiolabelled [3H]endomorphin-1 with a specific radioactivity of 2.35 TBq/mmol - prepared by catalytic dehalogenation of the diiodinated peptide precursor in the presence of tritium gas - is able to bind to a second, naloxone insensitive recognition site in rat brain membranes. Binding heterogeneity, i.e., the presence of higher (Kd = 0.4 nM / Bmax = 120 fmol/mg protein) and lower (Kd = 8.2 nM / Bmax = 432 fmol/mg protein) affinity binding components is observed both in saturation binding experiments followed by Schatchard analysis, and in equilibrium competition binding studies. The signs of receptor multiplicity, e.g., curvilinear Schatchard plots or biphasic displacement curves are seen only if the non-specific binding is measured in the presence of excess unlabeled endomorphin-1 and not in the presence of excess unlabeled naloxone. The second, lower affinity non-opioid binding site is not recognized by heterocyclic opioid alkaloid ligands, neither agonists such as morphine, nor antagonists such as naloxone. On the contrary, endomorphin-1 is displaced from its lower affinity, higher capacity binding site by several natural neuropeptides, including methionine-enkephalin-Arg-Phe, nociceptin-orphanin FQ, angiotensin and FMRF-amide. This naloxone-insensitive, consequently non-opioid binding site seems to be present in nervous tissues carrying low density or no µ-opioid receptors, such as rodent cerebellum, or brain of µ-opioid receptor deficient (MOPr-/-) transgenic or 'knock-out' (K.O.) mice. The newly described non-opioid binding component is not coupled to regulatory G-proteins, nor does it affect adenylyl cyclase enzyme activity. Taken together endomorphin-1 carries opioid and, in addition to non-opioid functions that needs to be taken into account when various effects of endomorphin-1 are evaluated in physiological or pathologic conditions.

Bacterial Infections After Kidney Transplantation: A Single-Center Experience.

BACKGROUND: Bacterial infections significantly affect graft loss and mortality after kidney transplantation (KT). We reviewed the frequencies, risk factors, and sources of bacterial infections after KT and their impact on graft and patient survivals. METHODS: The data of 154 kidney recipients who underwent transplantation from 2010 to 2015 were explored. Donor, recipient, and surgical parameters were collected, and source, type, and frequency of infectious complications, number of infective episodes, multidrug-resistant (MDR) bacteria, and the bacterial spectrum were established. RESULTS: The most common infection was urinary tract infection, which is in line with the literature. Out of the 154 recipients, 72.1% (n = 111) had at least 1 occasion of a bacterial infection episode with clinical symptoms. It occurred 0-43 months (mean, 19.5 mo) after transplantation. Ninety-three KT recipients (67.9%) developed 274 episodes of infection in the postoperative 1st year (1.8 episodes/patient/y), and 42 patients had admission to the hospital ward (5.2 d/patient/y). MDR was detected in 19.8% of the infections. CONCLUSIONS: A bacterial infection had no significant impact on survival by itself. However, in case of sepsis graft and patient survivals were lower compared with normal control subjects.

A Single-center Experience of Allograft Nephrectomies Following Kidney Transplantation.

INTRODUCTION: Approximately 10% of renal allografts fail during the first year after kidney transplantation (KT) and 3%-5% thereafter yearly. The indication and timing of allograft nephrectomy (AN) is still uncertain in some cases. The aim of this study was to reveal the ratio, etiology, and complications of AN at our center. MATERIAL AND METHODS: This is a retrospective study of all patients who underwent KT at our center between January 1, 2004 and December 31, 2014. We analysed the frequency, indications, timing, and complications of ANs. Also early and late ANs were compared. RESULTS: From 417 renal transplantations 49 ANs were performed (11.7%). The most frequent indications were chronic allograft nephropathy (25; 51%), arterial blood supply complications, like arterial thrombosis and stenosis (7; 15%), treatment-resistant acute rejection (3; 6%), and nonreparable ureter complications (3; 6%). The average time of AN since KT was 28 months. ANs were performed as an urgent setting in 16 (33%) cases, whereas it was elective in 33 cases (67%). The AN was executed within 30 days (early) in 11 (22%) cases, and thereafter (late) in 38 (78%) cases. The main indication for early AN was renal artery thrombosis (4; 37%) and chronic allograft nephropathy (25; 66%) for late AN. Surgical complications occurred in 10 cases (20; 4%). The most common was hematoma. CONCLUSION: The majority of the ANs were elective and late (more than 30 days; average time, 47 months). Leading indication was chronic allograft nephrectomy. Early ANs were urgent and life-saving in all cases.

Surgical Complications Following Kidney Transplantations: A Single-Center Study in Hungary.

Surgical complications (SCs) are still high potential causes of graft loss. The incidence has a huge amount of variations depending on many factors. Our aim was to study the postoperative technical complications following kidney transplantations (KTs) during a 5-year period between 2011 and 2015. In the observed time frame there were 47 SCs occurring in 32 (19.4%) patients of 165 KTs. Every complication was classified into 3 groups: vascular (11; 6.6%), urologic (16; 9.7%), and any others (20; 12.1%). The most common postoperative SCs in our center were hemorrhage (14; 8.5%), urinary leakage (12; 7.2%), and renal artery stenosis (6; 3.6%). Twenty-seven patients, 84% of those having had a SC, needed an intervention, mainly a surgical correction (28; 62%). Half of these interventions (21; 51%) were performed due to urologic reasons. As possible predicting factors, we studied the type of arterial and ureter anastomosis in relation to onset of vascular and urologic complications. There was no significant correlation. The same was true for any donor and/or recipient demographic parameters. However, the presence of SCs impaired both patient and graft survival. The cumulative 6-month, 1-, 3-, and 5-year patient survival rates were 97% versus 99%, 93% versus 99%, 84% versus 97%, and 84% versus 97% for patients with/without (w/wo) a SC, respectively (P = .028). The cumulative 6-month, 1-, 3-, and 5-year graft survival rates were 81% versus 96%, 77% versus 94%, 68% versus 86%, and 54% versus 86% for the same 2 groups, respectively (P = .003).

Surgical induction, histological evaluation, and MRI identification of cartilage necrosis in the distal femur in goats to model early lesions of osteochondrosis.

OBJECTIVE: Identify and interrupt the vascular supply to portions of the distal femoral articular-epiphyseal cartilage complex (AECC) in goat kids to induce cartilage necrosis, characteristic of early lesions of osteochondrosis (OC); then utilize magnetic resonance imaging (MRI) to identify necrotic areas of cartilage. DESIGN: Distal femora were perfused and cleared in goat kids of various ages to visualize the vascular supply to the distal femoral AECC. Vessels located on the axial aspect of the medial femoral condyle (MFC) and on the abaxial side of the lateral trochlear ridge were transected in eight 4- to 5-day-old goats to induce cartilage necrosis. Goats were euthanized 1, 2, 3, 4, 5, 6, 9, and 10 weeks post operatively and operated stifles were harvested. Adiabatic T1ρ relaxation time maps of the harvested distal femora were generated using a 9.4 T MR scanner, after which samples were evaluated histologically. RESULTS: Interruption of the vascular supply to the MFC caused lesions of cartilage necrosis in 6/8 goat kids that were demonstrated histologically. Adiabatic T1ρ relaxation time mapping identified these areas of cartilage necrosis in 5/6 cases. No significant findings were detected after transection of perichondrial vessels supplying the lateral trochlear ridge. CONCLUSIONS: Cartilage necrosis, characteristic of early OC, can be induced by interrupting the vascular supply to the distal femoral AECC in goat kids. The ability of high field MRI to identify these areas of cartilage necrosis in the AECC using the adiabatic T1ρ sequence suggests that this technique may be useful in the future for the early diagnosis of OC.

Articular osteochondrosis: a comparison of naturally-occurring human and animal disease.

BACKGROUND: Osteochondrosis (OC) is a common developmental orthopedic disease affecting both humans and animals. Despite increasing recognition of this disease among children and adolescents, its pathogenesis is incompletely understood because clinical signs are often not apparent until lesions have progressed to end-stage, and examination of cadaveric early lesions is not feasible. In contrast, both naturally-occurring and surgically-induced animal models of disease have been extensively studied, most notably in horses and swine, species in which OC is recognized to have profound health and economic implications. The potential for a translational model of human OC has not been recognized in the existing human literature. OBJECTIVE: The purpose of this review is to highlight the similarities in signalment, predilection sites and clinical presentation of naturally-occurring OC in humans and animals and to propose a common pathogenesis for this condition across species. STUDY DESIGN: Review. METHODS: The published human and veterinary literature for the various manifestations of OC was reviewed. Peer-reviewed original scientific articles and species-specific review articles accessible in PubMed (US National Library of Medicine) were eligible for inclusion. RESULTS: A broad range of similarities exists between OC affecting humans and animals, including predilection sites, clinical presentation, radiographic/MRI changes, and histological appearance of the end-stage lesion, suggesting a shared pathogenesis across species. CONCLUSION: This proposed shared pathogenesis for OC between species implies that naturally-occurring and surgically-induced models of OC in animals may be useful in determining risk factors and for testing new diagnostic and therapeutic interventions that can be used in humans.

Detailed modelling of delamination buckling of thin films under global tension.

Tensile specimens of metal films on compliant substrates are widely used for determining interfacial properties. These properties are identified by the comparison of experimentally observed delamination buckling and a mathematical model which contains the interface properties as parameters. The current two-dimensional models for delamination buckling are not able to capture the complex stress and deformation states arising in the considered uniaxial tension test in a satisfying way. Therefore, three-dimensional models are developed in a multi-scale approach. It is shown that, for the considered uniaxial tension test, the buckling and associated delamination process are initiated and driven by interfacial shear in addition to compressive stresses in the film. The proposed model is able to reproduce all important experimentally observed phenomena, like cracking stress of the film, film strip curvature and formation of triangular buckles. Combined with experimental data, the developed computational model is found to be effective in determining interface strength properties.

The role of harmonized, gas and liquid chromatography mass spectrometry in the discovery of the neolignan balanophonin in the fruit wall of Cirsium vulgare.

In order to identify and quantify fruit-lignans of Cirsium vulgare - authors introduced a special analysis system: with particular attention to the lignans enrichment/separation course. These synchronized, germination and enzymatic hydrolysis processes were followed by complementary gas and liquid chromatography, coupled with special mass selective detections (GC-MS, LC-MS/MS, LC-TOF/MS) and confirmed by nuclear magnetic resonance (NMR) spectroscopy. Mass fragmentations and NMR evidences, proved that the two main medicinal lignan constituents of the fruits of Cirsium vulgare are the neolignan-type, free balanophonin and the butyrolactone-type tracheloside. As novelty to the field, these two lignans of different chemical structures could be quantitatively extracted, separately from each others, without impurities. Balanophonin and tracheloside do accumulate in the fruits of C. vulgare, separately: balanophonin was found, in enormous high concentrations, in the fruit wall (23.2-24.9 mg/g), while in embryo part tracheloside was determined (20.3mg/g), exclusively. Consequently, the optimum source of balanophonin proved to be the fruit wall, while tracheloside, - providing trachelogenin upon enzymatic hydrolysis, - could be obtained from the embryo parts of fruits. As further novelties of the study balanophonin was identified and quantified at the first time with on-line chromatographic technique, in free form, without authentic standard compound.

Correlation between risk factors and subsequent surgical management following internal fixation of intracapsular femoral neck fractures in patients under the age of 60 years.

PURPOSE: Regarding intracapsular femoral neck fractures, the main focus of research is the correlation between fracture-related complications and prognostic factors. To evaluate the correlation between complications required surgery (fracture-related treatment) and, among others, several less extensively investigated prognostic factors (day of surgery, co-morbidities, hospital type) in a 2-year period following internal fixation in patients under the age of 60 years with intracapsular femoral neck fracture. METHODS: A retrospective analysis of femoral neck fractures occurring in Hungary in 2000 was undertaken, based on data obtained from the National Health Insurance Fund Administration. The data were validated and completed by a questionnaire carried out in all of the 60 institutions enrolled. The effects of prognostic factors were analyzed by uni- and multivariate logistic regression in three groups: all fracture-related treatments and non-prosthetic (NPT) and prosthetic treatments (PT). RESULTS: Out of 413 patients, 17.9% required further fracture-related treatment. In 7.7% of patients, NPT and in 10.2% of patients, PT was performed. Fracture displacement (odds ratio [OR] = 2.24), weekend surgery (OR = 2.35), infections (OR = 3.68), central nervous system-related co-morbidities (OR = 3.64), and the county hospital level of management (OR = 2.36) were associated with significantly increased risk for further surgery. CONCLUSIONS: To reduce the influence of risk factors, standardization of the substantive traumatologic and orthopedic professional guidelines, as well as the introduction of the "common orthopedic-trauma patient care" (British model) are suggested. To achieve high-quality standardized patient management, personal and material conditions are required to be accessible every day of the week. In the presence of co-morbidities, reduction of their harmful effects should be a major consideration by focusing on the patient in the peri-operative periods.

Complementary fragmentation pattern analysis by gas chromatography-mass spectrometry and liquid chromatography tandem mass spectrometry confirmed the precious lignan content of Cirsium weeds.

In this paper, as novelties to the field, it is confirmed at first, that the fruits of Cirsium species, regarded as injurious weeds, do contain lignans, two, different butyrolactone-type glycoside/aglycone pairs: the well known arctiin/arctigenin and the particularly rare tracheloside/trachelogenin species. These experiences were supported by gas chromatography-mass spectrometry (GC-MS), by liquid chromatography tandem mass spectrometry (LC-MS/(MS)) and by nuclear magnetic resonance (NMR) spectroscopy. The study reflects the powerful impact of the complementary chromatographic mass fragmentation evidences resulting in the identification and quantification, the extremely rare, with on line technique not yet identified and described, tracheloside/trachelogenin pair lignans, without authentic standard compounds. Fragmentation pattern analysis of the trimethylsilyl (TMS) derivative of trachelogenin, based on GC-MS, via two different fragmentation pathways confirmed the detailed structure of the trachelogenin molecule. The complementary chromatographic evidences have been unambiguously confirmed, by (1)H and (13)C NMR analysis of trachelogenin, isolated by preparative chromatography. Identification and quantification of the fruit extracts of four Cirsium (C.) species (C. arvense, C. canum, C. oleraceum, and C. palustre), revealed that (i) all four species do accumulate the tracheloside/trachelogenin or the arctiin/arctigenin butyrolactone-type glycoside/aglycone pairs, (ii) the overwhelming part of lignans are present as glycosides (tracheloside 9.1-14.5 mg/g, arctiin 28.6-39.3 mg/g, expressed on dry fruit basis), (iii) their acidic and enzymatic hydrolyses to the corresponding aglycones, to trachelogenin and arctigenin are fast and quantitative and (iv) the many-sided beneficial trachelogenin and arctigenin can be prepared separately, without impurities, excellent for medicinal purposes.

Association of season and pasture grazing with blood hormone and metabolite concentrations in horses with presumed pituitary pars intermedia dysfunction.

BACKGROUND: Pituitary pars intermedia dysfunction (PPID) is a risk factor for pasture-associated laminitis, which follows a seasonal pattern. HYPOTHESIS: Hormonal responses to season differ between PPID and unaffected horses. ANIMALS: Seventeen horses aged 8-30 years (14 horses ≥ 20 years of age). METHODS: Longitudinal observational study. Blood was collected monthly from August 2007 until July 2008 after pasture grazing and again after overnight stall confinement. Blood hormone and metabolite concentrations were measured and pasture grass samples were analyzed to determine carbohydrate content. Analysis of variance analysis for repeated measures was performed. RESULTS: Mean ACTH concentrations varied significantly over time (P < .001), with higher concentrations detected in August, September, and October compared with November-April. Pasture × time effects were detected for glucose and insulin concentrations, with peaks observed in September. Horses were retrospectively allocated to PPID (n = 8) and control (n = 9) groups on the basis of plasma ACTH concentrations. Changes in insulin concentrations over time differed in the PPID group when compared with the control group. Insulin concentrations were positively correlated with grass carbohydrate composition. CONCLUSIONS AND CLINICAL IMPORTANCE: PPID did not affect the timing or duration of the seasonal increase in ACTH concentrations, but higher values were detected in affected horses. Insulin concentrations differed between groups, but hyperinsulinemia was rarely detected. Glucose and insulin concentrations peaked in September when horses were grazing on pasture, which could be relevant to the seasonal pattern of laminitis.

Mass fragmentation study of the trimethylsilyl derivatives of arctiin, matairesinoside, arctigenin, phylligenin, matairesinol, pinoresinol and methylarctigenin: their gas and liquid chromatographic analysis in plant extracts.

The mass fragmentation patterns and the characteristic behavior of the trimethylsilyl (TMS) derivatives of the dibenzylbutyrolactone-type (arctiin, arctigenin, methylarctigenin, matairesinoside, matairesinol) and those of the diphenylperhydrofurotetrahydrofurane-type (phylligenin, pinoresinol) lignans, obtained by gas chromatography-mass spectrometry (GC-MS), were presented. It was shown that upon acidic hydrolysis the dibenzylbutyrolactone-type lignans are stable while the diphenylperhydrofurotetrahydrofurane-type ones decompose. As a novelty to the field we confirmed that the fragment species of the derivatized lignan glycosides, in the presence of excess hexamethyldisilazane, leaded to their in situ derivatization. Quantification of the selective fragment ions of the TMS derivatives by GC-MS, in respect of the ions found one by one, and concerning the selective fragment ions {SFI(s)} in total, provided acceptable reproducibilities, suitable for quantitation purposes: varying between 1.20% and 6.6% relative standard deviation percentages (RSD%). For characterization of the behavior of various type of lignans, analyses were performed with the untreated and with the trifluoroacetic acid hydrolyzed plant extracts, from the same sample, in parallel, both by GC-MS and by high performance liquid chromatography-mass spectrometry, working in the positive electron ionization mode (HPLC-ESPI-MS). The analysis of lignans in fruit and leaf extracts (obtained from the Arctium, Centaurea and Forsythia plants) was confirmed both by GC-MS and by HPLC-ESPI-MS. Our multicomponent system (including the identification and quantification of sugars, sugar alcohols, and several members of various homologous series of acids, anthraquinones and flavonoids) has been extended to the analysis of lignan glycosides and to the free lignans. Reproducibilities in the quantitation of lignans in plant matrices, as averages on GC and HPLC basis, varied between 0.9% and 11% (RSD). The distribution of the lignan constituents was presented for 5 Arctium, for 8 Centaurea and for 4 Forsythia plant extracts: the total of lignan contents varied between 0.42 and 87.9 mg/g, respectively.

Measurement of C-peptide concentrations and responses to somatostatin, glucose infusion, and insulin resistance in horses.

REASONS FOR PERFORMING STUDY: Hyperinsulinaemia is detected in horses with insulin resistance (IR) and has previously been attributed to increased pancreatic insulin secretion. Connecting peptide (C-peptide) can be measured to assess pancreatic function because it is secreted in equimolar amounts with insulin and does not undergo hepatic clearance. HYPOTHESIS: A human double antibody radioimmunoassay (RIA) detects C-peptide in equine serum and concentrations would reflect responses to different stimuli and conditions. METHODS: A validation procedure was performed to assess the RIA. Six mature mares were selected and somatostatin administered i.v. as a primed continuous rate infusion, followed by 50 nmol human C-peptide i.v. Insulin and C-peptide concentrations were measured in horses (n = 6) undergoing an insulin-modified frequently sampled i.v. glucose tolerance test, and in horses with insulin resistance (n = 10) or normal insulin sensitivity (n = 20). RESULTS: A human RIA was validated for use with equine sera. Endogenous C-peptide secretion was suppressed by somatostatin and median (range) clearance rate was 0.83 (0.15-1.61) ml/min/kg bwt. Mean + or - s.d. C-peptide-to-insulin ratio significantly (P = 0.004) decreased during the glucose tolerance test from 3.60 + or - 1.95 prior to infusion to 1.03 + or - 0.18 during the first 20 min following dextrose administration. Median C-peptide and insulin concentrations were 1.5- and 9.5-fold higher, respectively in horses with IR, compared with healthy horses. CONCLUSIONS: Endogenous C-peptide secretion decreases in response to somatostatin and increases after dextrose infusion. Results suggest that relative insulin clearance decreases as pancreatic secretion increases in response to dextrose infusion. Hyperinsulinaemia in insulin resistant horses may be associated with both increased insulin secretion and decreased insulin clearance. POTENTIAL RELEVANCE: Both C-peptide and insulin concentrations should be measured to assess pancreatic secretion and insulin clearance in horses.