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1.
Gen Comp Endocrinol ; 329: 114127, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36150474

RESUMO

Understanding the hypothalamic factors regulating reproduction facilitates maximising the reproductive success of breeding programmes and in the management and conservation of threatened species, including African lions. To provide insight into the physiology and pathophysiology of the hypothalamic-pituitary-gonadal reproductive axis in lions, we studied the luteinising hormone (LH) and steroid hormone responses to gonadotropin-releasing hormone (GnRH) and its upstream regulator, kisspeptin. Six young (13.3 ± 1.7 months, 56.2 ± 4.3 kg) and four adult (40.2 ± 1.4 months, 174 ± 6 kg) male lions (Ukutula Conservation Centre, South Africa) were used in this study. Lions were immobilised with a combination of medetomidine and ketamine and an intravenous catheter was placed in a jugular, cephalic or medial saphenous vein for blood sampling at 10-min intervals for 220 min. The ten-amino acid kisspeptin which has full intrinsic activity (KP-10, 1 µg/kg) and GnRH (1 µg/kg) were administered intravenously to study their effects on LH and steroid hormone plasma concentrations, measured subsequently by ELISA and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. Basal LH levels were similarly low between the age groups, but testosterone and its precursor levels were higher in the adult animals. Adult lions showed a significant LH response to KP-10 (10-fold) and GnRH (11-fold) administration (p < 0.05 and P < 0.001, respectively) whereas in young lions LH increased significantly only in response to GnRH. In adults alone, testosterone and its precursors steadily increased in response to KP-10, with no significant further increase in response to GnRH. Plasma levels of glucocorticoids in response to KP-10 remained unchanged. We suggest that provocative testing of LH and steroid stimulation with kisspeptin provides a new and sensitive tool for determining reproductive status and possibly an index of exposure to stress, environmental insults such as disease, endocrine disruptors and nutritional status. 272 words.


Assuntos
Kisspeptinas , Leões , Animais , Masculino , Hormônio Liberador de Gonadotropina , Cromatografia Líquida , Status Social , Espectrometria de Massas em Tandem , Hormônio Luteinizante , Reprodução , Testosterona , Meio Ambiente
2.
Front Hum Neurosci ; 15: 692054, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483864

RESUMO

The most important part of sleep quality assessment is the automatic classification of sleep stages. Sleep staging is helpful in the diagnosis of sleep-related diseases. This study proposes an automatic sleep staging algorithm based on the time attention mechanism. Time-frequency and non-linear features are extracted from the physiological signals of six channels and then normalized. The time attention mechanism combined with the two-way bi-directional gated recurrent unit (GRU) was used to reduce computing resources and time costs, and the conditional random field (CRF) was used to obtain information between tags. After five-fold cross-validation on the Sleep-EDF dataset, the values of accuracy, WF1, and Kappa were 0.9218, 0.9177, and 0.8751, respectively. After five-fold cross-validation on the our own dataset, the values of accuracy, WF1, and Kappa were 0.9006, 0.8991, and 0.8664, respectively, which is better than the result of the latest algorithm. In the study of sleep staging, the recognition rate of the N1 stage was low, and the imbalance has always been a problem. Therefore, this study introduces a type of balancing strategy. By adopting the proposed strategy, SEN-N1 and ACC of 0.7 and 0.86, respectively, can be achieved. The experimental results show that compared to the latest method, the proposed model can achieve significantly better performance and significantly improve the recognition rate of the N1 period. The performance comparison of different channels shows that even when the EEG channel was not used, considerable accuracy can be obtained.

3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(9): 546-50, 2008 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19087607

RESUMO

OBJECTIVE: To investigate the effect of rapid canine distalization through distraction of the periodontal ligament after reducing interseptal bone resistance. METHODS: Twenty canines in 11 patients who needed first premolar extractions were involved. A tooth-borne, custom-made distractor was bonded right after the first premolar extraction and the interseptal bone resistance reduction. Three days post-operatively, the distractor was activated 0.1 mm three times a day. Orthodontic models, panoramic radiographs, periapical radiographs, electrical vitality test were assessed pre- and post distraction procedure and 3 months after the completion of the procedure. RESULTS: The distraction procedure was completed in 18 to 35 days [mean (25.6 +/- 4.7) days], with the distal displacement of the canines ranging from 3.53 to 8.29 mm [mean (5.56 +/- 1.32) mm]. The canines showed a mean of 12.20 degrees distal tipping and 18.53 degrees rotation. The anchorage teeth showed an average of (0.76 +/- 0.75) mm mesial movement. The mesial contact point of incisors showed a mean of (0.67 +/- 0.55) mm lingual movement. There was no significant root resorption or long-time change on pulp vitality after distraction. CONCLUSIONS: The canine distalization through distraction of the periodontal ligament after reducing interseptal bone resistance was an effective approach to move canines rapidly.


Assuntos
Dente Canino/cirurgia , Ligamento Periodontal/cirurgia , Reabsorção da Raiz/cirurgia , Técnicas de Movimentação Dentária/métodos , Adolescente , Feminino , Humanos , Masculino
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-230012

RESUMO

<p><b>OBJECTIVE</b>To study a Chinese pedigree with Hailey-Hailey disease (HHD) and examine the ATP2C1 gene mutation in this family.</p><p><b>METHOD</b>All exons of ATP2C1 gene were analyzed with polymerase chain reaction and DNA sequencing in all patients of this family and 100 unrelated population-match controls.</p><p><b>RESULTS</b>We identified a novel heterozygous nucleotide A --> G transition at position 235 - 2 in intron 3 of ATP2C1 gene. This splice site mutation was not found in the healthy members of this pedigree and in the controls.</p><p><b>CONCLUSION</b>The splicing mutation can affect the result of transcription and translation, and it is a specific novel mutation of ATP2C1 gene.</p>


Assuntos
Humanos , Povo Asiático , ATPases Transportadoras de Cálcio , Genética , Mutação , Linhagem , Pênfigo Familiar Benigno , Genética
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-230004

RESUMO

<p><b>OBJECTIVE</b>To identify the mutations of ED1 gene in a family with X-linked hypohidrotic ectodermal dysplasia</p><p><b>METHODS</b>Eight coding exons of ED1 gene of two patients with clinically confirmed X-linked hypohidrotic ectodermal dysplasia, their parents, and 100 unrelated population-matched control were amplified by polymerase chain reaction. The products were further analyzed by direct sequencing.</p><p><b>RESULTS</b>Two patients with X-linked hypohidrotic ectodermal dysplasia in this pedigree showed a point mutation at nucleotide 1 045 ( A > G) . Meanwhile, heterozygous double peaks of nucleotide G and A at the same position were found in their mother, but not in their father and 100 unrelated population-matched controls.</p><p><b>CONCLUSION</b>The c. 1 045A > G mutation of ED1 gene may be the pathologic cause of this Chinese family with X-linked hypohidrotic ectodermal dysplasia.</p>


Assuntos
Humanos , Povo Asiático , Displasia Ectodérmica Anidrótica Tipo 1 , Genética , Ectodisplasinas , Genética , Estudos de Associação Genética , Mutação , Linhagem
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-230003

RESUMO

<p><b>OBJECTIVE</b>To analyze the mutation of TSC gene in two sporadic patients with tuberous sclerosis complex (TSC).</p><p><b>METHODS</b>All the coding exons of TSC1 and TSC2 genes of these two patients, unaffected member in the two families, and 100 unrelated population-matched controls were amplified by polymerase chain reaction. The products were analyzed by direct sequencing.</p><p><b>RESULT</b>Two TSC2 gene mutations (c. 268C > T, c. 5 227C > T) were identified in two patients, but not in their family members and in 100 unrelated population-matched controls.</p><p><b>CONCLUSION</b>These two mutations are the cause of the clinical phenotypes of these two sporadic patients with TSC.</p>


Assuntos
Humanos , Estudos de Associação Genética , Mutação , Esclerose Tuberosa , Genética , Proteínas Supressoras de Tumor , Genética
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