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Abstract 623: Angiotensin Receptor Activation Contributes to Glucose Intolerance and Increased Insulin Resistance Independent of Elevated Systolic Blood Pressure, Adiposity and Dyslipidemia in a Model of Metabolic Syndrome. Hypertension 2013. [DOI: 10.1161/hyp.62.suppl_1.a623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Activation of the renin-angiotensin system (RAS) leads to an increase in blood pressure and onset of insulin resistance (IR); however, the contributions of increased blood pressure and AT1 activation independently on the manifestation of IR are not well defined. The goal of this study was to determine the contribution of elevated blood pressure, independent of RAS, to the onset of IR in a model of metabolic syndrome. To address the hypothesis that AT1 activation, and not elevated blood pressure independently, is the principal contributor of obesity-associated IR, we measured changes in systolic blood pressure (SBP), adiposity, plasma triglycerides (TG), glucose tolerance, and insulin resistance index (IRI) in four groups of rats: 1) lean strain-control Long Evans Tokushima Otsuka (LETO; n=5), 2) obese Otsuka Long-Evans Tokushima Fatty (OLETF; n=7), 3) OLETF + angiotensin receptor blocker (ARB; 10 mg olmesartan/kg; n=8), and 4) OLETF + calcium channel blocker (CCB; 5 mg amlodipine/kg; n=7). ARB treatment alleviated the obesity-related increase in mean SBP, while the decrease with CCB remained 10.2 mmHg greater than LETO. ARB (0.51 g/100g body mass) and CCB (0.64 g/100g body mass) reduced mean relative retroperitoneal fat mass and mean plasma triglycerides (28.4 and 27.4 mg/dL respectively) compared to OLETF, but both remained greater (1.7, 1.57 g/100g body mass and 28.94, 29.94 mg/dL respectively) than LETO. ARB improved glucose tolerance by 4605.94 of 34965.94 and mean calculated IRI by 5581429.5 of 17398363, but CCB had no detectable effect on either. Despite relatively similar reductions in SBP, adiposity and plasma TG (principal components of metabolic syndrome), CCB did not improve glucose tolerance and IRI (additional metrics of metabolic syndrome), while ARB did, demonstrating that AT1 activation is the primary factor contributing to the development of impaired glucose metabolism and regulation during metabolic syndrome, independent of the hypertension, adiposity and dyslipidemia. Thus, targeting RAS to improve the consequences of metabolic syndrome appears to be prudent and effective.
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Fresh cow mastitis monitoring on day 3 postpartum and its relationship to subsequent milk production. J Dairy Sci 2011; 93:5673-83. [PMID: 21094739 DOI: 10.3168/jds.2009-2885] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Accepted: 07/19/2010] [Indexed: 11/19/2022]
Abstract
The purpose was to determine the association of milk California Mastitis Test (CMT), somatic cell concentration (SCC), and milk differential cell count results on day 3 postcalving with subsequent lactation production and health events. On d 3 postcalving, the CMT was performed and quarter milk samples were collected from 130 dairy cows. Quarter SCC and milk differential cell counts were determined. Microbiology on duplicate quarter milk samples was used to determine the presence of intramammary infection by major or minor pathogens. Production measures obtained using Dairy Herd Improvement Association testing were 150-d standardized and summit milks. Milk culture results on a cow basis included 82 (63.1%) samples with no growth, 31 (23.9%) with major pathogens, and 17 (13.1%) with minor pathogens. Milk culture results comparing cows with no growth to those with any growth (major or minor pathogens) were not associated with statistically significant differences in milk production. Milk culture results comparing cows with major pathogens to those with no growth and minor pathogens combined were associated with statistically significant differences in 150 d milk. Milk production did not differ for cows with CMT results above and below a cut-off of trace, and for SCC results above and below cut-offs of 200,000, 300,000, and 400,000/mL, respectively. Statistically significant differences in milk production were found for cows above and below cut-offs for percentage neutrophils in milk and for absolute neutrophil counts. Associations were found for milk production and number of quarters (0, 1, 2, or 3 and 4 combined) above respective cut-offs for SCC, percentage neutrophils in milk, and absolute numbers of neutrophils in milk, but not for CMT. Milk production differed for cows experiencing any health event versus those with no health event. The most commonly recorded health event was clinical mastitis. Statistically significant associations were detected between health events and milk culture results, SCC, neutrophil percentage, and neutrophil absolute counts. Results of the present investigation indicate that milk monitoring on d 3 of lactation using milk neutrophil percentage or neutrophil absolute counts may be useful as an indication of subsequent milk production.
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Decreased oxidative stress in prehepatic portal hypertensive rat livers following the induction of diabetes. Clin Exp Pharmacol Physiol 2004; 31:169-73. [PMID: 15008960 DOI: 10.1111/j.1440-1681.2004.03963.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
1. Oxidative stress (OS) is a biological entity indicated as being responsible for several pathologies, including diabetes. Diabetes can also be associated with human cirrhosis. Portal hypertension (PH), a major syndrome in cirrhosis, produces hyperdynamic splanchnic circulation and hyperaemia. The present study was designed to investigate the occurrence of OS in prehepatic PH rat livers following the induction of diabetes. 2. Five groups of rats were used: control, sham operated, chronic diabetes (induced with a single dose of streptozotocin at 60 mg/kg, i.p.), prehepatic PH and chronic diabetic plus prehepatic PH. The occurrence of OS was determined in liver homogenates by measuring hydroperoxide-initiated chemiluminescence and the activity of anti-oxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). 3. Prehepatic PH produced a significant increase in hydroperoxide-initiated chemiluminescence in the liver compared with control and sham-operated rats, whereas the liver in chronic diabetic rats showed no difference. However, chemiluminescence values decreased almost by 50% in the chronic diabetic plus prehepatic PH group. Concomitantly, the activities of the anti-oxidant enzymes in chronic diabetes, prehepatic PH and chronic diabetic plus prehepatic PH groups were decreased (P < 0.05 vs control and sham-operated groups). 4. Livers from the chronic diabetic group did not show any evidence of the occurrence of OS, whereas the prehepatic PH group showed the occurrence of OS. The association of PH and chronic diabetes resulted in a significant decrease in the occurrence of OS, which could be explained by an anti-oxidant response to an OS.
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A type XI collagen mutation leads to increased degradation of type II collagen in articular cartilage. Osteoarthritis Cartilage 2004; 12:314-20. [PMID: 15023383 DOI: 10.1016/j.joca.2003.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2003] [Accepted: 12/03/2003] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine in articular cartilage whether degraded type II collagen is more abundant in Col11a1 mutant cho/+ than in age-matched +/+ mice and whether collagen degradation occurs in a generalized or localized fashion. DESIGN Knee joints from cho/+ and +/+ mice at 6, 9, 12 and 15 months of age were dissected, fixed, cryosectioned, and stained with antibody COL2-3/4m against denatured type II collagen using a FITC-conjugated secondary antibody. Sections were viewed and photographed under a fluorescence microscope and areas of staining were quantified. RESULTS Before 12 months of age, little degraded collagen staining was detectable in +/+ or cho/+ mice. By 15 months, however, cho/+ mice showed significantly more degraded type II collagen than age-matched controls. Degraded collagen staining was localized at the articular surface, not distributed generally throughout the articular cartilage. CONCLUSIONS The results suggest a model in which cumulative biomechanical stresses trigger increased collagen synthesis and degradation in both +/+ and cho/+ mice at around 12 months of age. Cho/+ mice, however, are less able to synthesize and assemble normal replacement collagen fibrils because of the Col11a1 mutation. Degradation is further activated, resulting in the accumulation of degraded type II collagen in the articular cartilage extracellular matrix. Similar mutations that do not overtly affect skeletal development may likewise predispose humans to increased collagen degradation and resultant osteoarthritis.
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Chemical extraction methods to assess bioavailable arsenic in soil and solid media. JOURNAL OF ENVIRONMENTAL QUALITY 2003; 32:876-884. [PMID: 12809288 DOI: 10.2134/jeq2003.8760] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Soil ingestion by children is an important pathway in assessing public health risks associated with exposure to arsenic-contaminated soils. Soil chemical methods are available to extract various pools of soil arsenic, but their ability to measure bioavailable arsenic from soil ingestion is unknown. Arsenic extracted by five commonly used soil extractants was compared with bioavailable arsenic measured in vivo by immature swine (Sus scrofa) dosing trials. Fifteen contaminated soils that contained 233 to 17 500 mg kg(-1) arsenic were studied. Soil extractants were selected to dissolve surficially adsorbed and/or readily soluble arsenic (water, 1 M sodium acetate, 0.1 M Na2HPO4/0.1 M NaH2PO4) and arsenic in Fe and Mn oxide minerals (hydroxylamine hydrochloride, ammonium oxalate). The mean percent of total arsenic extracted was: ammonium oxalate (53.6%) > or = hydroxylamine hydrochloride (51.7%) > phosphate (10.5%), acetate (7.16%) > water (0.15%). The strongest relationship between arsenic determined by soil chemical extraction and in vivo bioavailable arsenic was found for hydroxylamine hydrochloride extractant (r = 0.88, significant at the 0.01 probability level). Comparison of the amount of arsenic extracted by soil methods with bioavailable arsenic showed the following trend: ammonium oxalate, hydroxylamine hydrochloride > in vivo > phosphate, acetate > water. The amount of arsenic dissolved in the stomach (potentially bioavailable) is between surficially adsorbed (extracted by phosphate or acetate) and surficially adsorbed + nonsurficial forms in Fe and Mn oxides (extracted by hydroxylamine hydrochloride or ammonium oxalate). Soil extraction methods that dissolve some of the amorphous Fe, such as hydroxylamine hydrochloride, can be designed to provide closer estimates of bioavailable arsenic.
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Abstract
BACKGROUND AND PURPOSE To describe the rationale, protocol and procedure for the treatment of prostate cancer using high dose rate brachytherapy (HDR-BT) and a non-fixed template technique. MATERIALS AND METHODS Between July 1991 and December 1998, 491 patients with carcinoma of the prostate were treated using HDR-BT and a non-fixed template technique. AJC stages T(1C)-T(3B), patients with prior transurethral resections of the prostate (TURP) and gland volumes >60 cm(3), were included. Flexible cystoscopy, fluoroscopy and transrectal ultrasound (TRUS) were used and 17 flexiguides were inserted through the perineum. Dosimetry was carried out using localization films. Treatment volume was defined at 4-6 mm outside the peripheral catheters. BT consisted of two implants, separated by 1 week, with two fractions given per implant for a total of four HDR fractions. Dose prescription to the treatment volume was 6 Gy (HDR) per fraction, with an additional dose of 0.5 to 0.75 Gy given where required. RESULTS Patients with glands >60 cm(3), narrow pubic arches and TURP defects were treated satisfactorily. Symptoms of urinary irritation occurred with variable intensity and abated rapidly 2 weeks after the procedures. There was no high-grade chronic rectal morbidity and most patients reported no rectal symptoms or treatment-related chronic urinary incontinence. CONCLUSIONS The non-fixed template technique allowed flexibility in flexiguide placement to encompass large glands (>60 cm(3)), extracapsular extension and seminal vesicle involvement without the need for additional flexiguides. Also, small pubic arches and TURP defects posed little problem in positioning the flexiguides. This versatility resulted in complete treatment volume coverage of the prostate.
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High dose rate transperineal interstitial brachytherapy for cervical cancer: high pelvic control and low complication rates. Int J Radiat Oncol Biol Phys 1999; 45:105-12. [PMID: 10477013 DOI: 10.1016/s0360-3016(99)00124-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
PURPOSE To report the clinical outcome for cervical carcinoma treated with external beam pelvic radiotherapy and interstitial high dose rate (IS-HDR) brachytherapy. METHODS AND MATERIALS Between July 1991 and June 1996, 62 patients with locally advanced stage cervical carcinoma or early stage carcinoma that precluded satisfactory tandem and ovoid insertion were treated. Most patients received 36 Gy (range: 25 Gy-45 Gy) external beam radiotherapy (EBRT) to the pelvis prior to brachytherapy implant. EBRT was continued, with central shielding, to a dose of 50 Gy to the pelvic sidewalls. HDR Iridium-192 brachytherapy was given in 6 fractions of 5.5 to 6.0 Gy. The mean follow-up was 40 months. RESULTS Stage distribution was: Stage IB (12), Stage IIA (1), Stage IIB (26), Stage IIIA (6), Stage IIIB (13), and Stage IVA (4). The overall local tumor control was 94%. Local control rates by FIGO stage were Stage I (12/12) 100%, Stage II (25/27) 93%, Stage III (18/19) 95%, and Stage IV (3/4) 75%. The regional pelvic control rates were overall 81%, Stage I (12/12) 100%, Stage II (22/27) 81%, Stage III (15/19) 79%, and Stage IV (1/4) 25%. Distant metastasis developed in 20 patients (32%). The actuarial 5-year disease-free survival was for all patients 48%, Stage I 81%, Stage II 47%, Stage III 39%, and Stage IV O%. Grade 3-4 delayed morbidity resulting from treatment, occurred in 6.5% (4/62) of patients. A fistula without local recurrence occurred in 1.6% (1/62) patients. CONCLUSIONS We report excellent local and regional pelvic control results using a 6 fraction IS-HDR brachytherapy protocol for cervical carcinoma. The incidence of severe complications is low and suggests that a consistent brachytherapy technique and multiple HDR fractions are therapeutically advantageous to patients treated for cervical carcinoma.
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Abstract
Because the HDR brachytherapy treatments are delivered within minutes and on an outpatient basis, HDR brachytherapy is very well tolerated by patients and offers complete radiation safety. Published studies2, 11, 12, 13, 16, 17, 18, 22, 24, 25 have shown high local clinical and biochemical control rates. Chronic complications have been acceptably low. Very low rates of urinary incontinence and high sexual potency rates have been reported. Gastrointestinal morbidity has been minimal. The development of Ir-192 HDR afterloading brachytherapy and refinements in the dosimetry have ushered in a new era in prostate brachytherapy. The control of the radiation dose and the ability to shape the radiation treatment envelope using a stepping source have allowed a giant step forward in radiation oncology technology. It is now possible to deliver tumoricidal doses of radiation conformally to the prostate while minimizing the dose to the bladder, urethra, and rectum. At present, HDR afterloaded brachytherapy is the optimal whole-organ and tumor-specific conformal radiation therapy for prostate cancer.
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The effect of segmental bronchoprovocation with allergen on airway lymphocyte function. Am J Respir Crit Care Med 1997; 156:1421-8. [PMID: 9372655 DOI: 10.1164/ajrccm.156.5.9703054] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We hypothesized that allergen-induced airway eosinophilia is linked to activation or recruitment of T cells in the airway and generation of interleukin-5 (IL-5). To evaluate this hypothesis, we performed bronchoscopy with segmental antigen bronchoprovocation in 12 atopic subjects. Bronchoalveolar lavage (BAL) was done 5 min and 48 h after challenge with saline or antigen. Airway cells were isolated and then stimulated ex vivo with a T-cell mitogen, phytohemagglutinin (PHA), and cytokine release was determined. Cells retrieved from the saline-challenged segment secreted principally interferon-gamma (IFN-gamma) and IL-2. In contrast, cells obtained 48 h after allergen challenge secreted high levels of IL-5 and small but increased amounts of IL-4, IL-10, and granulocyte-macrophage colony-stimulating factor (GM-CSF). Although CD4+ T cells were a major source of IL-5, there were no significant changes in the relative proportion of CD4+ cells in response to bronchoprovocation. Additionally, ex vivo secretion of IL-5 by airway cells correlated closely with amounts of IL-5 and eosinophils present in the bronchoalveolar lavage fluid (BALF). These observations suggest that following exposure to allergen, airway T cells are functionally but not phenotypically different from resident airway T cells, and that T cells within the airway contribute to eosinophilic airway inflammation through the secretion of IL-5.
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Cytokine profiles of stimulated blood lymphocytes in asthmatic and healthy adolescents across the school year. J Interferon Cytokine Res 1997; 17:481-7. [PMID: 9282829 DOI: 10.1089/jir.1997.17.481] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation.
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Glucose, glycogen and triglyceride metabolism, as well as prostaglandin production in uterine strips and in embryos from diabetic pregnant rats. Influences of the presence of substrate in the incubation medium. PROSTAGLANDINS 1993; 46:417-31. [PMID: 8278619 DOI: 10.1016/0090-6980(93)90078-l] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
"In vitro" isometric developed tension (IDT) and frequency of contractions (FC), glucose (Glu), glycogen (GLY) and triglyceride (TG) metabolism, as well as prostaglandin PGE2 and PGE1 production, were studied in uterine strips and in embryos isolated from controls and diabetic rats at day 10 of pregnancy. The IDT and the FC, at 0 time or after a 60 min incubation, were not different in controls and in preparations from diabetic animals when the uterine strips were incubated in glucose or in glucose-free medium (p > 0.05). The production of 14CO2 and 14C-lactate from 14C-glucose were lower in the diabetic group than in controls (p < or = 0.05). Indomethacin (10(-6) M), an inhibitor of prostaglandin synthesis, failed to modify these results. Labelled Glu metabolism by isolated embryos was similar (p > 0.05) in controls and in embryos obtained from diabetic mothers. On the other hand, the initial TG and GLY levels were higher (p < or = 0.05) in diabetic uterine tissues than in controls. However, the values of TG and GLY in embryos obtained from both experimental groups were similar (p > 0.05). TG levels in uterine strips suspended in Glu or in Glu-free medium did not differ (p > 0.05) at 0 time (postisolation) and at 60 min, either in controls or in diabetic rats. However, Gly levels in uterine strips from diabetic animals, decreased significantly at 60 min in tissues incubated in Glu or in Glu-free medium (p < or = 0.05). In controls, uterine Gly content decreased (p < or = 0.05) only at 60 min time when the strips were incubated in Glu-free medium. Finally, uterine tissue from controls as well as from diabetic pregnant rats release more PGE2 than PGE1 into the incubation medium (p < or = 0.001). Nevertheless, secretion of PGE2 and PGE1 was similar in both experimental groups and was not modified by the presence or absence of glucose. In summary, we found differences in uterine metabolism of glucose, glycogen and triglycerides in controls and in diabetic rats, but metabolic differences have not been detected between embryos obtained from controls and from diabetic mothers.
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Eicosanoid production by uterine strips and by embryos obtained from diabetic pregnant rats. PROSTAGLANDINS 1993; 45:487-95. [PMID: 8321917 DOI: 10.1016/0090-6980(93)90124-p] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Eicosanoid production by uterine strips and by embryos obtained from normal and diabetic rats at day 10 of pregnancy was studied. It was found that the release of 6-keto-PGF1 alpha (representing PGI2 synthesis) and of LTB4 was less in preparations from diabetic animals than in controls. The production of TXB2 (indicating the formation of TXA2) by uterine tissue obtained from diabetic rats was almost double that of controls. The synthesis and release of eicosanoids when tissues were incubated in glucose-containing solution or in glucose-free medium were similar, with the exception of LTB4, which was diminished with uterine strips from diabetic rats. The mean number of embryos in control pregnant rats (12.4 +/- 0.5) and in diabetic mothers (10.1 +/- 1.3) was not significantly different, but in 4 of the 14 diabetic rats studied, all of their embryos were resorbed. Although embryos released large amounts of PGF2 and PGE2, and small amounts of 6-keto-PGF1 alpha, TXB2 and LTB4, the amounts of each eicosanoid in control and diabetic groups were similar. The present results indicate that the diabetic state, which induces alterations in uterine eicosanoid production, do not influence arachidonic metabolism in their corresponding embryos.
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Subunit structure and higher order assembly of the hemocyanins of five members of the Naticidae family of marine gastropods: Calinaticina oldroydii (Dall), Euspira heros (Say), Neverita duplicata (Say), Polinices draconis (Dall), and Polinices lewisii (Gould). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1990; 97:631-6. [PMID: 2085950 DOI: 10.1016/0305-0491(90)90099-f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
1. The hemocyanins of the Naticidae family, E. heros, N. duplicata, P. draconis, P. lewisii and C. oldroydii were investigated by sedimentation velocity and scanning transmission electron microscopy. 2. At pH 8.0, 0.05 M Mg2+ E. heros hemocyanin is found to be predominantly in the tri-decameric state with a sedimentation coefficient (So20,w) of 131.3 (+/- 0.6) S. While the hemocyanin of N. duplicata is also mainly in the 130 S form, the hemocyanin of C. oldroydii is largely in the di-decameric form with a sedimentation coefficient close to 100 S. Other Naticidae hemocyanins, those of P. lewisii and P. draconis, have mixtures of the 100 S and 130 S di- and tri-decamers, and minor amounts of 150 S and faster sedimenting components. 3. The average particle masses based on STEM measurements are 8.85 x 10(6), 1303 x 10(6), and 17.1 x 10(6) da for the di-, tri-, and tetra-decameric assemblies of hemocyanin. 4. The subunit mol. wts of C. oldroydii hemocyanin and the published values for E. heros hemocyanin at alkaline pHs and in the presence of 8.0 M urea range from 4.2 x 10(5) to 4.8 x 10(5), suggesting the same decameric organization of the sub-assemblies of the Naticidae hemocyanins as for other molluscan hemocyanins. 5. The appearance of the larger hemocyanin particles in the electron micrographs support the hypothesis for their assembly that was based on similar studies of the hemocyanins of the Melongenidae family. According to this scheme the formation of higher aggregates is accomplished by the tail-to-head addition of each decameric unit to a central di-decamer which itself has the tail-to-tail Mellema and Klug arrangement of decamers. In this model all the higher aggregates terminate from either end with the same "collar" ends.
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Abstract
The incidence and course of development of diabetes was studied for 12 months after subtotal pancreatectomy in five strains of rats. Operations were performed on 5-7-week old-male animals weighing 100-140 g, and, subsequently, rats with fasting blood glucose levels greater than 8.3 mmol/l were considered to be diabetic. In Füllinsdorf Albino rats, the proportion of diabetic animals gradually increased during the course of the experiment to a maximum of 83%. In Holtzman and Piebald rats, the highest incidence (58% and 28% respectively) was observed 2-3 months after surgery, after which partial remission of their diabetes occurred. Spontaneously hypertensive rats completely recovered from an initially mild diabetic state within 6 months of the operation. In Lewis rats, only a small number of animals (15%) became diabetic towards the end of the experiment. The severity of diabetes also differed considerably between strains. The pancreatic insulin content in diabetic rats was 2%-7% and in operated non-diabetic rats 17%-26% of values in non-operated control animals of the same age and strain. However, in the operated non-diabetic rats, glucose tolerance and the insulin response to glucose were also impaired. It is concluded that there are marked inter-strain differences in rats concerning the incidence and development of diabetes following subtotal pancreatectomy.
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Modified oscillation behavior and decreased D-3-hydroxybutyrate dehydrogenase activity in diabetic rat liver mitochondria. Arch Biochem Biophys 1982; 214:581-8. [PMID: 6284028 DOI: 10.1016/0003-9861(82)90063-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Blood concentrations of glucose, insulin and free fatty acids in shortly thyroxine-treated dogs: effects of alpha-blockade and isoproterenol. Horm Metab Res 1982; 14:101. [PMID: 7040189 DOI: 10.1055/s-2007-1018935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Physical therapy in cardiac rehabilitation. AMERICAN ARCHIVES OF REHABILITATION THERAPY 1979; 27:9. [PMID: 10249292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Experimental hyperthyroidism in dogs. Evaluation and effects on blood sugar, serum insulin and free fatty acids during glibenclamide infusion test. Horm Metab Res 1975; 7:382-5. [PMID: 810396 DOI: 10.1055/s-0028-1093732] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The effects of hyperthyroidism on the BS, serum IRI and FFA responses to HB 419 were studied. Hyperthyroidism, induced by l-thyroxine administration, caused an increase in body temperature, respiratory rate, BS, serum FFA and PBI basal levels. Fasting serum cholesterol was reduced, and body weight, basal metabolic and heart rates, as well as basal serum insulin level failed to be affected. The hypoglycaemic response to HB 419 was moderately facilitated by hyperthyroidism, despite of inducing an impairment in the insulin secretory response. Serum FFA profile, similarly shaped in hyperthyroid dogs and in euthyroid controls, was shifted upwards by hyperthyroid condition. Results are discussed.
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Prof. Bernardo Alberto Houssay (1887-1971). THE PHYSIOLOGIST 1973; 16:697-9. [PMID: 4586229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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[Cyril Norman Hugh Long (1901-1970)]. REVISTA DE LA SOCIEDAD ARGENTINA DE BIOLOGIA 1970; 46:61-2. [PMID: 4946321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Abstract
The stimulatory effect of two monoamine-oxidase inhibitors, nialamide and tranylcypromine, upon insulin secretion was studied using the in vitro rat slice pancreas incubation technic. It was found that these drugs stimulated insulin release in the presence of low levels of glucose. They were also able to enhance the insulin release elicited by high levels of glucose.
These results would explain, at least in part, the protective role of MAOI in some types of experimental and clinical diabetes.
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