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1.
J Endocrinol Invest ; 32(6): 512-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19474519

RESUMO

OBJECTIVE: Primary hyperparathyroidism (PHPT), a common endocrine condition, is usually caused by sporadically occurring parathyroid adenoma. A subset of patients carry germline mutations in genes such as MEN1 (multiple endocrine neoplasia type 1), HRPT2 (hyperparathyroidism 2), and CASR (calcium-sensing receptor) predisposing to syndromic forms of PHPT or familial isolated hyperparathyroidism (FIHP). Recently, germline mutations in two novel genes AIP (aryl hydrocarbon receptor-interacting protein) and CDKN1B (cyclin-dependent kinase inhibitor 1B) have been found to be associated with endocrine tumors. The purpose of this study was to evaluate the role of MEN1, HRPT2, CASR, AIP, and CDKN1B genes in PHPT patients with clinical features suggestive of genetic predisposition. PATIENTS AND DESIGN: Medical records of patients treated for PHPT from 1974 to 2001 at Oulu University Hospital were reviewed. Patients with multiglandular or recurrent/persistent disease, other MEN1- related manifestations, aged 40 yr or younger at onset or with a family history of PHPT/MEN1-related tumor were invited to the study. Twenty patients with previously diagnosed MEN1 were excluded. Participants were interviewed and blood samples obtained for biochemical screening and mutation analysis of MEN1, HRPT2, CASR, AIP, and CDKN1B. RESULTS: Of the 56 invited patients, 29 took part in the study. One patient was found to carry the c. 1356_1367del12 MEN1 founder mutation. Mutations in other genes were not detected. CONCLUSIONS: Apart from MEN1, mutations in other genes predisposing to PHPT seem to be rare or non-existing in Northern Finnish PHPT patients. No evidence was found for a role of AIP or CDKN1B in PHPT predisposition.


Assuntos
Hiperparatireoidismo Primário/genética , Neoplasias das Paratireoides/genética , Adulto , Inibidor de Quinase Dependente de Ciclina p27 , DNA/química , DNA/genética , Feminino , Finlândia , Predisposição Genética para Doença , Variação Genética , Humanos , Hiperparatireoidismo Primário/patologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/patologia , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Receptores de Detecção de Cálcio/química , Receptores de Detecção de Cálcio/genética , Estudos Retrospectivos , Análise de Sequência de DNA , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Adulto Jovem
2.
Eur J Endocrinol ; 157(3): 285-94, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17766710

RESUMO

OBJECTIVE: The existence of genotype-phenotype correlation in multiple endocrine neoplasia type 1 (MEN1) is controversial. Two founder mutations of the MEN1 gene in Northern Finland gave us an opportunity to compare clinical features among heterozygotes of different mutations. DESIGN AND METHODS: Study cohort included 82 MEN1 heterozygotes who were tested for MEN1 during the years 1982-2001. Medical records were reviewed for manifestations of MEN1, other tumours and cause of death by the end of August 2003. Logistic regression analysis was used in evaluating the impact of age, gender and mutational status of affected heterozygotes on the likelihood of developing manifestations of MEN1. RESULTS: Founder mutations 1466del12 and 1657insC were found in 39 and 29 individuals, and D418N, G156R and R527X mutations in 9, 3 and 2 individuals respectively. Except for pituitary adenoma and nonfunctional pancreatic tumour (NFPT), age was a risk factor for all the disease manifestations. For NFPT, frameshift/nonsense mutations (1657insC, R527X) gave an odds ratio (OR) of 3.26 (95% confidence intervals (CI), 1.27-8.33; P = 0.014) compared with in-frame/missense mutations (1466del12, D418N, G156R); including the founder mutation carriers (n = 68) only, the 1657insC mutation gave an OR of 3.56 (CI, 1.29-9.83; P = 0.015). For gastrinoma, in-frame/missense mutations predicted the risk with an OR of 6.77 (CI, 1.31-35.0; P = 0.022), and in the founder mutations group the 1466del12 mutation gave an OR of 15.09 (CI, 1.73-131.9, P = 0.014). CONCLUSIONS: In this study population, NFPT was more common in the frameshift/nonsense or 1657insC mutation carriers, whereas gastrinoma was more common in the in-frame/missense or 1466del12 mutation carriers.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/genética , Neoplasia Endócrina Múltipla Tipo 1/mortalidade , Proteínas Proto-Oncogênicas/genética , Adolescente , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/mortalidade , Adulto , Idoso , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/mortalidade , Criança , Códon sem Sentido , Feminino , Finlândia/epidemiologia , Efeito Fundador , Mutação da Fase de Leitura , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/mortalidade , Genótipo , Humanos , Hiperparatireoidismo Primário/genética , Hiperparatireoidismo Primário/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Fenótipo , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/mortalidade , Fatores de Risco
3.
Physiol Behav ; 88(1-2): 116-23, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16643971

RESUMO

Although reindeer are well adapted to limited food resources during winter, semi-domesticated reindeer are regularly fed when snow conditions are bad in order to prevent starvation. Feeding sometimes results in health problems and loss of animals. This study was made to assess if activity pattern in reindeer could be used as a tool for the reindeer herder in early detection of animals that are not adapting to feeding. The frequency of 10 behavioural categories was recorded in five groups of penned, eight-month-old, female semi-domesticated reindeer. Three reindeer per group were fitted with heart rate monitors. Lying was the most frequent behaviour, whilst there were few cases of agonistic behaviour. Heart rate varied during the day, with peaks during feeding and low heart rates in the early morning. Restricted feed intake resulted in more locomotion and seeking but less ruminating compared to feeding ad libitum. This was followed by a generally lower heart rate in reindeer in the restricted groups compared to controls. Subsequent feeding with different combinations of lichens, silage and pellets ad libitum resulted initially in significantly more of the animals lying curled up, compared to controls, combined with increased heart rates. As the experiment continued the general activity pattern, as well as the heart rate, gradually became more similar in all groups. Lying curled was the behavioural indicator most consistently affected by feed deprivation and adaptation to feeding and may thus be a useful indicator to distinguish individual reindeer that are not adjusting to feeding.


Assuntos
Aclimatação , Ração Animal , Criação de Animais Domésticos/métodos , Frequência Cardíaca/fisiologia , Atividade Motora/fisiologia , Rena/fisiologia , Animais , Comportamento Animal , Feminino , Monitorização Fisiológica , Apoio Nutricional
4.
Opt Lett ; 31(5): 598-600, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16570410

RESUMO

A simple method for frequency locking a frequency-doubled Nd:YAG laser to the center of line 1109 of the iodine absorption spectrum is described. The 31.6 GHz frequency shift provided by stimulated-Brillouin scattering from a single-mode silica fiber provides a probe signal that lies on the edge of line 1105 of the iodine spectrum. We adjust the frequency of the laser to maintain the transmission of a 5 cm iodine absorption cell at a value that places the unshifted laser line in the center of line 1109.

5.
Artigo em Inglês | MEDLINE | ID: mdl-16325441

RESUMO

Plasma total protein (TP), albumin (ALB) and globulin (GLOB) concentrations and albumin/globulin ratio (A/G) were analysed from blood samples collected from free-ranging reindeer (Rangifer tarandus tarandus) herds at varying times of year. The same parameters were followed in nine captive reindeer with varying protein and energy intake. Variation in the blood constituents of free-ranging reindeer was analysed in relation to different extrinsic and intrinsic factors and compared to findings from captive animals, allowing the analysis of effects of protein and energy intake. There was large overall variation in TP, ALB, GLOB and A/G ratio in the free-ranging animals, ranging between 36-110 g/L, 18-59 g/L, 17-59 g/L and 0.5-2.1. The variation between months and years was significant for all variables except the A/G ratio, where no year effect was noted. Increase in live body mass was associated with a small significant increase and pregnancy with a small significant decrease in all dependent variables, except for the A/G ratio. Age did not have a significant effect on any of the blood constituents when body mass was included in the same model. In captive animals, feeding lichens with low protein content was related to a significant decline in TP, ALB and GLOB, but not in the A/G ratio, whereas feeding commercial ration increased plasma TP, ALB and GLOB significantly. Extrinsic factors such as season and year explained majority of variation in the blood constituents of free-ranging reindeer, whereas body mass, pregnancy and age had only a minor influence. It is concluded that plasma TP and ALB, and to a lesser extent GLOB and A/G ratio may serve as nutritional biomarkers of reindeer.


Assuntos
Proteínas Sanguíneas/metabolismo , Dieta , Rena/fisiologia , Albumina Sérica/metabolismo , Soroglobulinas/metabolismo , Animais , Proteínas Sanguíneas/análise , Feminino , Análise de Regressão , Estações do Ano , Albumina Sérica/análise , Soroglobulinas/análise , Fatores de Tempo
6.
Theriogenology ; 63(6): 1775-88, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15763117

RESUMO

The endocrinology was studied throughout pregnancy in reindeer (Rangifer tarandus tarandus) located in Oulu, Finland (65 degrees N, 25 degrees E) with 13 captive, semi domestic adult females. Blood samples were analyzed for plasma progesterone (P4), estradiol (E2) and estrone sulphate (E1SO4), 15-ketodihydro-PGF2alpha (PG-metabolite) and pregnancy associated glycoproteins (PAG). The mean plasma P4 concentration peaked twice during gestation: at around 24 and three weeks prior to calving. In pregnant females the plasma PAG concentration increased over basal concentrations 21-30 days after the estimated day of conception and peaked at the time of calving. The concentrations of E2 and E1SO4 remained low until 60 days before calving when a rapid increase was found for both hormones. The mean plasma concentration of PG-metabolite increased throughout pregnancy to a maximum at parturition. The estimated mean (range) gestation length was 216 (212-220) days. Judged from measures on reproductive organs collected from 86 free-ranging, semi-domestic female reindeer of unknown age presented for slaughter at Roros, Norway (63 degrees N, 11 degrees E) in the second week of December 1999, it was concluded that the breeding season lasted from early September until the end of November. The results also showed that plasma PAG concentration could provide a tool for detection of pregnancy in reindeer.


Assuntos
Estrona/análogos & derivados , Hormônios/sangue , Testes de Gravidez/veterinária , Prenhez/sangue , Rena/sangue , Animais , Animais de Zoológico , Estradiol/sangue , Estrona/sangue , Feminino , Finlândia , Idade Gestacional , Glicoproteínas/sangue , Gravidez , Proteínas da Gravidez/sangue , Progesterona/sangue , Prostaglandinas/sangue
7.
Domest Anim Endocrinol ; 26(2): 87-98, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14757182

RESUMO

The effects of manual blood sampling and remote blood sampling using automatic blood sampling equipment (ABSE) on plasma cortisol and catecholamine concentrations were studied on eight adult female reindeer (Rangifer tarandus tarandus). Contemporary body temperatures and heart rates were also recorded to determine their utility as other possible stress indicators. The animals were blood sampled once every hour with ABSE on 9-10 May and then by manual blood sampling on 13-14 May. Animals were also fitted with equipment to record heart rate and body temperature. Heart rate and body temperature were also recorded continuously without blood sampling on 17-18 May in undisturbed control conditions. Plasma cortisol concentrations were five-to-six fold greater during manual blood sampling compared to sampling with ABSE (F(1,3) = 13.34, P < 0.05). Plasma noradrenaline concentrations were significantly higher (F(1,3) = 22.98, P < 0.05) during manual blood sampling compared to sampling with ABSE, whereas plasma adrenaline concentrations did not differ. Heart rate was higher during manual blood sampling compared to control values. Body temperature was significantly higher during manual sampling compared to values recorded without blood sampling (F(1,4)= 31.65, P < 0.01). In conclusion, plasma cortisol concentration provides an excellent indicator of handling stress in reindeer. The use of ABSE for blood sampling enables measurements of plasma cortisol levels close to basal concentrations that may be used for reference values in studies where indicators of physiological stress are required.


Assuntos
Coleta de Amostras Sanguíneas/psicologia , Coleta de Amostras Sanguíneas/veterinária , Rena/sangue , Estresse Fisiológico/sangue , Estresse Fisiológico/veterinária , Animais , Temperatura Corporal/fisiologia , Epinefrina/sangue , Feminino , Manobra Psicológica , Frequência Cardíaca/fisiologia , Hidrocortisona/sangue , Norepinefrina/sangue , Rena/psicologia
8.
Acta Vet Scand ; 43(2): 85-97, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12173506

RESUMO

Wet belly, when the reindeer becomes wet over the lower parts of the thorax and abdomen, sometimes occurs in reindeer during feeding. In a feeding experiment, 11 out of 69 reindeer were affected by wet belly. The problem was first observed in 7 animals during a period of restricted feed intake. When the animals were then fed standard rations, 3 additional animals fed only silage, and 1 fed pellets and silage, became wet. Four animals died and 1 had to be euthanized. To investigate why reindeer developed wet belly, we compared data from healthy reindeer and reindeer affected by wet belly. Urea, plasma protein, glucose, insulin and cortisol were affected by restricted feed intake or by diet but did not generally differ between healthy reindeer and those with wet belly. The wet animals had low body temperature and the deaths occurred during a period of especially cold weather. Animals that died were emaciated and showed different signs of infections and stress. In a second experiment, with 20 reindeer, the feeding procedure of the most affected group in the first experiment was repeated, but none of the reindeer showed any signs of wet belly. The study shows that wet belly is not induced by any specific diet and may affect also lichen-fed reindeer. The fluid making the fur wet was proven to be of internal origin. Mortality was caused by emaciation, probably secondary to reduced energy intake caused by diseases and/or unsuitable feed.


Assuntos
Ração Animal/efeitos adversos , Rena , Dermatopatias/veterinária , Animais , Proteínas Sanguíneas/análise , Temperatura Corporal , Ingestão de Energia , Feminino , Privação de Alimentos , Glucose/análise , Hidrocortisona/análise , Hiperidrose/etiologia , Hiperidrose/veterinária , Insulina/análise , Líquens , Distribuição Aleatória , Dermatopatias/etiologia , Ureia/sangue
9.
Acta Vet Scand ; 43(3): 135-44, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12564543

RESUMO

The aim of the study was to test the performance of a silver wire modified version of the coded telemetric heart rate monitor Polar Vantage NV (PVNV) and to measure heart rate (HR) in a group of captive reindeer calves during different behaviour. The technical performance of PVNV HR monitors was tested in cold conditions (-30 degrees C) using a pulse generator and the correlation between generated pulse and PVNV values was high (r=0.9957). The accuracy was tested by comparing the HR obtained with the PVNV monitor with the standard ECG, and the correlation was significant (r=0.9965). Both circadian HR and HR related to behavioural pattern were recorded. A circadian rhythm was observed in the HR in reindeer with a minimum during night and early morning hours and maximum at noon and during the afternoon, the average HR of the reindeer calves studied being 42.5 beats/min in February. The behaviour was recorded by focal individual observations and the data was synchronized with the output of the HR monitors. Running differed from all other behavioural categories in HR. Inter-individual differences were seen expressing individual responses to external and internal stimuli. The silver wire modified Polar Vantage NV provides a suitable and reliable tool for measuring heart rate in reindeer, also in natural conditions.


Assuntos
Comportamento Animal , Monitorização Fisiológica/veterinária , Rena/fisiologia , Telemetria/veterinária , Animais , Eletrocardiografia , Feminino , Finlândia , Frequência Cardíaca , Telemetria/instrumentação
10.
Physiol Biochem Zool ; 74(6): 907-16, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11731982

RESUMO

Variation in plasma urea and creatinine concentration and plasma urea:creatinine ratio (U:C) were studied in semidomestic free-ranging reindeer (Rangifer tarandus tarandus) on the Norwegian mainland, in wild Svalbard reindeer (Rangifer tarandus platyrhynchus), and in captive reindeer maintained either on a lichen-based diet or a protein-rich concentrate to investigate whether these parameters could be used as indicators of the nutritional status of reindeer. In the mainland animals, plasma creatinine concentration was high in winter and early spring and decreased by two-thirds toward the summer. The overall range in mean plasma creatinine concentration (+/-SE) was from 90+/-1.26 to 280+/-2.88 micromol/L. Mean plasma urea concentration (+/-SE) varied from 2.46+/-0.10 in winter up to 17.44+/-0.29 mmol/L in summer and autumn. Month of sampling explained 65% and 90% of the variation in plasma urea and creatinine concentrations, respectively, indicating that seasonality in the diet had the greatest influence on these parameters. Reindeer given lichens as the only feed showed an increase in plasma creatinine and a decrease in plasma urea concentration. Food restriction caused a temporary elevation in urea level but had no significant effect on plasma creatinine concentration. The slight effect of energy intake on urea and creatinine levels was supported by the fact that severe undernutrition in the Svalbard reindeer population had only a small effect on plasma urea and creatinine levels. Protein-rich pellet feed increased plasma urea from around 3 mmol/L to above 10 mmol/L and reduced creatinine concentrations to less than 100 micromol/L, suggesting that the protein content of forage is an important determinant of these blood parameters. Mean U:C ratio (+/-SE) in plasma varied from 8.9+/-0.28 to 120.8+/-1.88. Ratios above 20 appeared when protein intake was low and energy intake was restricted or when protein intake was high. Low ratios occurred when protein intake was low but energy intake adequate. Plasma urea and creatinine concentrations and the U:C ratio showed complex dynamics that were affected by both season and the protein and feed intake. We conclude that they appear to be difficult to interpret as single measures of nutritional status of reindeer.


Assuntos
Creatinina/sangue , Dieta , Proteínas Alimentares/metabolismo , Rena/fisiologia , Ureia/sangue , Animais , Animais Selvagens , Ingestão de Energia , Feminino , Líquens , Estado Nutricional , Estações do Ano
11.
J Parasitol ; 86(4): 763-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10958453

RESUMO

Six female reindeer calves were inoculated intraruminally with various doses of Trichinella muscle larvae. Four calves were inoculated with T. nativa, receiving 15,000 (n = 1), 5,000 (1), and 2,500 (2) larvae each. Two calves were inoculated with 5,000 T. spiralis larvae each. Blood samples were collected twice per week for total white blood cell (WBC) and differential counts and for serology using enzyme-linked immunosorbent assay (ELISA) based on T. spiralis excretory-secretory antigen. On day 56, the calves were slaughtered and muscle samples were examined according to the standard digestion method for Trichinella larvae. Blood samples were also collected twice a week from 4 uninoculated, but otherwise similar, reindeer calves corralled separately. Both the total WBC and eosinophil counts of the inoculated animals were, on average, higher during the experimental period. All the inoculated calves seroconverted, showing an increase in the optical density (OD) in the ELISA starting between day 23 and day 27 postinoculation. Very few muscle larvae (<0.08 larvae/g [lpg]) were to be found from the animals inoculated with T. nativa, but about 4 and 6 lpg were recovered from the masseter muscles of those inoculated with T. spiralis.


Assuntos
Rena/parasitologia , Trichinella spiralis , Triquinelose/veterinária , Animais , Anticorpos Anti-Helmínticos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Contagem de Leucócitos/veterinária , Camundongos , Músculo Esquelético/parasitologia , Trichinella/imunologia , Trichinella/isolamento & purificação , Trichinella spiralis/imunologia , Trichinella spiralis/isolamento & purificação , Triquinelose/sangue , Triquinelose/parasitologia
12.
Int J Circumpolar Health ; 59(1): 33-7, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10850005

RESUMO

In order to understand the effects of solar irradiance on calcium metabolism we measured serum 25-hydroxycholecalciferol and total calcium levels monthly in 6 female nonpregnant reindeer maintained in the Oulu area (65 degrees N). Mean monthly serum total calcium levels varied slightly and the highest levels were seen in October. Serum 25-hydroxycholecalciferol levels were highest in October but the monthly variation was also slight. The small monthly variation of the analytes' abundance and the fact that they peaked not until 4 months after the longest day, (i.e. the main stimulus for vitamin D synthesis) could have something to do with the supplementation of this vitamin in the diet of the captive reindeer.


Assuntos
Calcifediol/sangue , Cálcio/sangue , Fotoperíodo , Rena/fisiologia , Estações do Ano , Raios Ultravioleta , Animais , Feminino
13.
Artigo em Inglês | MEDLINE | ID: mdl-10327601

RESUMO

Annual cycle of type I collagen formation and degradation and antler growth was studied in six adult female reindeer, Rangifer tarandus tarandus. Blood samples were collected twice a week during 1 year. Antler length was measured weekly during the antler growth period. An assay for human PICP, the carboxyterminal propeptide of type I procollagen, was used as an indicator of type I collagen formation and an assay for bovine ICTP, the carboxyterminal telopeptide of type I collagen, as an indicator of type I collagen degradation. PICP was clearly increased during the antler growth period. Also ICTP was slightly elevated during antler growth, but the highest values were found in autumn and winter. Our statistical analysis revealed that changes in lagged values (from 3 to 6 weeks) of PICP could be linked to the subsequent changes in the growth rate of the antler, although the highest values of PICP were found during the final third of antler growth. ICTP had significant predictive power as well, but the connection with the growth rate seemed more immediate than that of PICP. In conclusion, antler collagen synthesis can be predicted by PICP, but also ICTP was related to the antler growth.


Assuntos
Chifres de Veado/fisiologia , Colágeno/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Rena/fisiologia , Animais , Bovinos , Colágeno Tipo I , Feminino , Humanos , Modelos Lineares , Rena/sangue , Rena/crescimento & desenvolvimento , Estações do Ano , Fatores de Tempo
14.
Appl Opt ; 37(12): 2464-72, 1998 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-18273181

RESUMO

An equation to predict the intensity of the multiply scattered lidar return is presented. Both the scattering cross section and the scattering phase function can be specified as a function of range. This equation applies when the cloud particles are larger than the lidar wavelength. This approximation considers photon trajectories with multiple small-angle forward-scattering events and one large-angle scattering that directs the photon back toward the receiver. Comparisons with Monte Carlo simulations, exact double-scatter calculations, and lidar data demonstrate that this model provides accurate results.

15.
J Endocrinol ; 141(3): 527-33, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8071651

RESUMO

The reindeer in its natural habitat is subject to great annual variations in ambient temperature, illumination and nutrition. To ascertain the effect of these environmental factors on thyroid function, serum thyroid-stimulating hormone (TSH), thyroxine (T4), tri-iodothyronine (T3) and reverse T3 (rT3) concentrations were measured four times a year (2 June, 8 October, 21 November, and 24 February) in 14 animals housed outdoors at latitude 69 degrees 10'N. They all showed statistically significant (P < 0.05) seasonal changes. Serum TSH and T4 were highest in February (623 +/- 30 ng/ml and 287 +/- 19 nmol/l respectively). TSH was lowest in October (318 +/- 47 ng/ml) and T4 in November (199 +/- 19 nmol/l). The T3 concentration was highest in November (3.0 +/- 0.3 nmol/l) and lowest in June (1.8 +/- 0.2 nmol/l). In contrast, rT3 was highest in June (3.6 +/- 1.2 nmol/l) and lowest in November (1.9 +/- 0.6 nmol/l). Thus, there was an inverse relationship between T3 and rT3 (linear regression r = -0.406, P < 0.01). TSH, T4, T3 and rT3 responses to exogenous thyrotrophin-releasing hormone (synthetic TRH; 500 micrograms i.m.) were determined in ten animals. The magnitude of their response to TRH was significantly (P < 0.05) dependent on the time of year. When compared with the control level all the parameters rose significantly (P < 0.05). The greatest rise in serum TSH occurred in October (219 +/- 151%) and the smallest in February (66 +/- 53%).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Meio Ambiente , Rena/sangue , Estações do Ano , Hormônios Tireóideos/sangue , Hormônio Liberador de Tireotropina/farmacologia , Tireotropina/sangue , Fenômenos Fisiológicos da Nutrição Animal , Animais , Feminino , Luz , Temperatura , Glândula Tireoide/efeitos dos fármacos , Tiroxina/sangue , Tri-Iodotironina/sangue , Tri-Iodotironina Reversa/sangue
17.
Endocrinology ; 130(3): 1645-52, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1537312

RESUMO

Daily patterns of pineal function were studied in different seasons in 10 adult semidomesticated female reindeer and 5 prepubertal calves living in a natural arctic environment at latitude 69 degrees 10'N. Serum samples for melatonin RIA were collected every 4 h for 24 h in October (10 h of light, 14 h of darkness and 8 h of light, 16 h of darkness), December (24 h of darkness), March (13 h of light, 11 h of darkness), and June (24 h of light). A significant daily variation in serum melatonin levels was observed in the adult reindeer, with peak values (20-50 ng/liter) occurring during the night in autumn, winter, and spring, but not summer. The daytime values at 13 h (5-10 ng/liter) were constant throughout the year. Total daily amounts of melatonin, the duration of peak levels, and maximal concentrations were significantly lower in spring and summer than before the rut in autumn. The exposure of adult animals to artificial darkness from bright sunlight on August 1 and September 21 resulted in an immediate increase in serum melatonin concentrations. The 2-week-old calves had detectable serum melatonin levels, but no daily rhythm in the spring, whereas a rhythm was detectable by the first autumn, only to disappear unexpectedly during the first winter and return in the spring. At the age of 16 months, the calves had serum melatonin concentrations similar to those in the adults. Our present results show that the continuous illumination experienced during the summer abolished the normal daily melatonin rhythm. This does not seem to be related to organic changes in the pineal gland, since exposure to darkness during the summer increased melatonin levels. The highest melatonin secretion occurred in the autumn and was evidently associated with the rut. Similarly, the daily melatonin rhythm of an adult type observed in the calves at the age of 16 months may be related to the observation that most calves were in rut. Thus, a high rhythmical melatonin secretion appears to relate to puberty and the initiation of heat in female reindeer.


Assuntos
Animais Recém-Nascidos/sangue , Ritmo Circadiano/fisiologia , Melatonina/sangue , Rena/sangue , Estações do Ano , Animais , Feminino , Luz , Glândula Pineal/metabolismo , Glândula Pineal/fisiologia , Radioimunoensaio , Rena/fisiologia
18.
Appl Opt ; 30(19): 2668-70, 1991 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20700258

RESUMO

Lidar systems that analyze backscatter with Fabry-Perot étalons exhibit range-dependent spectral transmission functions. A fiber-optic scrambler is described that reduces this range dependence.

20.
Appl Opt ; 22(23): 3716-24, 1983 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18200256

RESUMO

A high spectral resolution lidar technique to measure optical scattering properties of atmospheric aerosols is described. Light backscattered by the atmosphere from a narrowband optically pumped oscillator-amplifier dye laser is separated into its Doppler broadened molecular and elastically scattered aerosol components by a two-channel Fabry-Perot polyetalon interferometer. Aerosol optical properties, such as the backscatter ratio, optical depth, extinction cross section, scattering cross section, and the backscatter phase function, are derived from the two-channel measurements.

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