Development of the gonads in the triploid (ZZW and ZZZ) fowl, Gallus domesticus, and comparison with normal diploid males (ZZ) and females (ZW)

1995 ◽  
Vol 7 (5) ◽  
pp. 1185 ◽  
Author(s):  
M Lin ◽  
MH Thorne ◽  
IC Martin ◽  
BL Sheldon ◽  
RC Jones
Keyword(s):  
Young Adults ◽  
Gonadal Development ◽  
Gallus Domesticus ◽  
Seminiferous Epithelium ◽  
Seminiferous Tubules ◽  
Duct System ◽  
Diploid Males ◽  
The Right ◽  
Duct Development

Gonadal development in fowls aged from 1 day to more than 4.5 years was studied in 63 ZZW and 16 ZZZ triploid crossbreds and compared with normal diploid males (ZZ) and females (ZW). In the ZZW fowl, the right gonad developed into a testis (although this occurred earlier in the ZZ genotype), and a structurally-abnormal excurrent duct system containing some malformed spermatids and spermatozoa was associated with the gonad of young adults. The left gonad was an ovotestes at hatching and no excurrent ducts were associated with it. The ovarian component was much less developed than that in the ZW genotype-it started to degenerate by 1 week of age, and most of the oocytes had disappeared by about 3 weeks of age. The seminiferous tubules developed in the medullary region, but only abnormal spermatozoa were produced. Leukocytes infiltrated both gonads at about 9 months of age and the seminiferous epithelium had degenerated in most fowls over 1 year old. In ZZZ fowl, gonadal and excurrent duct development was normal, but occurred earlier than in the ZZ genotype. However, meiosis and spermiogenesis were abnormal and malformed spermatozoa were produced. The heads of spermatozoa from the ducts deferens were about 1.4-times longer in the ZZZ genotype than in the ZZ genotype, indicating that the former may be producing some diploid spermatozoa.

scholarly journals Morphological study of the testis of adult Sudanese Chicken : gallus domesticus

2022 ◽  
Vol 7 (1) ◽  
Author(s):  
Al-Bajuri Salwa Ismail Abd al-Qadir
Keyword(s):  
Morphological Study ◽  
Gallus Domesticus ◽  
Cold Weather ◽  
Seminiferous Tubules ◽  
Left Testis ◽  
Adult Chicken ◽  
Mean Diameter ◽  
Hot Season ◽  
The Mean ◽  
The Right

Morphological study of the testis of adult Sudanese Chicken : gallus domesticus The adult chicken testes were two bean - shaped , large and soft , the left testis is usually higher in position and larger in size than the right one . The testis is active during cold weather with the mean diameter of the seminiferous tubules being 126^m in the chicken . it is less active during the hot season with the mean diameter of the seminiferous tubules being 135^m in the chicken. The non - breeding season seemed to be characterized by a decline in the spermatogenic activity only and not by complete spermatogenesis

Asymmetry in Event-Related Potentials to Simulated Auditory Motion in Children, Young Adults, and Seniors

2002 ◽  
Vol 13 (01) ◽  
pp. 001-013 ◽  
Author(s):  
James Jerger ◽  
Rebecca Estes
Keyword(s):  
Young Adults ◽  
Right Hemisphere ◽  
Apparent Movement ◽  
Event Related Potentials ◽  
Auditory Evoked Responses ◽  
Age Related ◽  
Related Potentials ◽  
Velocity Information ◽  
The Right ◽  
Age Range

We studied auditory evoked responses to the apparent movement of a burst of noise in the horizontal plane. Event-related potentials (ERPs) were measured in three groups of participants: children in the age range from 9 to 12 years, young adults in the age range from 18 to 34 years, and seniors in the age range from 65 to 80 years. The topographic distribution of grand-averaged ERP activity was substantially greater over the right hemisphere in children and seniors but slightly greater over the left hemisphere in young adults. This finding may be related to age-related differences in the extent to which judgments of sound movement are based on displacement versus velocity information.

scholarly journals Seminoma and sertolioma in non-cryptorchid dog – case report

2021 ◽  
Vol 15 (4) ◽  
pp. 281-286
Author(s):  
Guilherme Mantuani Silva ◽  
Isabela Cristina de Oliveira ◽  
Rodrigo Samuel de Toledo ◽  
Juliana Evangelista Bezerril ◽  
Gabriela Maria Benedetti Vasques ◽  
...  
Keyword(s):  
Physical Examination ◽  
Ultrasound Examination ◽  
Histopathological Examination ◽  
Seminiferous Tubules ◽  
Biochemical Tests ◽  
Predisposing Factor ◽  
Left Testicle ◽  
Spindle Cells ◽  
Mixed Breed ◽  
The Right

The most common testicular neoplasms in dogs are seminoma, leydigocytoma and sertolioma, affecting middle--aged and elderly dogs, where cryptorchidism is a predisposing factor, as well as some breeds. It can occur alone or, less fren-quently, concurrently, generally affecting the same testicle. This study aimed to report the case of a non-cryptorchid 14-year--old mixed breed dog diagnosed with seminoma and sertolioma, each in a testicle. The animal showed an increase in scrotal volume, with no changes in other clinical parameters on physical examination. On ultrasound examination, it was possible to observe alterations suggestive of neoplasia in both testicles and prostatic alteration suggestive of benign prostatic hyperplasia. Complementary blood count and biochemical tests were performed and, as treatment, orchiectomy was performed. Fragments were collected from both testicles and sent for histopathological examination. Microscopy of the left testicle showed the presence of round cells, multiple and evident nucleoli, cells in different phases of mitosis and binucleation, these changes being compa-tible with seminoma. In contrast, in the right testicle, spindle and elongated cells (pseudo-lobular) were observed, presence of long cytoplasmic projections with rounded ovoid nucleus, spindle cells and degeneration of seminiferous tubules, compatible with sertolioma. It was observed that physical examination associated with ultrasound was efficient to detect the presence of neoplasms, being validated by histopathological examination. Orchiectomy was an assertive treatment indicated for this case.

scholarly journals A novel stimulus paradigm for simultaneous recording of monaural and binaural frequency following response for identification of binaural interaction component

2020 ◽  
Author(s):  
Srividya Grama Bhagavan ◽  
Mohan Kumar Kalaiah
Keyword(s):  
Young Adults ◽  
Pure Tone ◽  
Stimulus Presentation ◽  
Simultaneous Recording ◽  
The Novel ◽  
Frequency Following Response ◽  
Binaural Interaction ◽  
The Right ◽  
Interaction Component

AbstractThe objective of the study was to investigate whether monaural frequency following response (FFR) of right and left ear and binaural FFR could be obtained in the same recording using a novel stimulus presentation paradigm, for the purpose of identification the BIC. Twenty six young adults participated in the study. The FFR was recorded for 220 Hz pure-tone using a novel stimulus paradigm. The pure-tone was presented sequentially to two ears. Initially, the pure-tone was presented to the right ear, then to both ears, and finally to the left ear. The FFR could be elicited from all participants (all three responses: right ear, left ear, and both ears) in the same recording using the novel stimulus presentation paradigm used in the present study. The novel stimulus presentation paradigm used in the present study could be used for obtaining monaural and binaural FFRs in the same recording for identification of BIC.

scholarly journals Minireview: Transcriptional Regulation of Gonadal Development and Differentiation

Endocrinology ◽  
2005 ◽  
Vol 146 (3) ◽  
pp. 1035-1042 ◽  
Author(s):  
Susan Y. Park ◽  
J. Larry Jameson
Keyword(s):  
Germ Cells ◽  
Sertoli Cells ◽  
Leydig Cells ◽  
Cell Types ◽  
Gonadal Development ◽  
Targeted Mutagenesis ◽  
Seminiferous Tubules ◽  
Molecular Pathways ◽  
Theca Cells ◽  
Main Cell

The embryonic gonad is undifferentiated in males and females until a critical stage when the sex chromosomes dictate its development as a testis or ovary. This binary developmental process provides a unique opportunity to delineate the molecular pathways that lead to distinctly different tissues. The testis comprises three main cell types: Sertoli cells, Leydig cells, and germ cells. The Sertoli cells and germ cells reside in seminiferous tubules where spermatogenesis occurs. The Leydig cells populate the interstitial compartment and produce testosterone. The ovary also comprises three main cell types: granulosa cells, theca cells, and oocytes. The oocytes are surrounded by granulosa and theca cells in follicles that grow and differentiate during characteristic reproductive cycles. In this review, we summarize the molecular pathways that regulate the distinct differentiation of these cell types in the developing testis and ovary. In particular, we focus on the transcription factors that initiate these cascades. Although most of the early insights into the sex determination pathway were based on human mutations, targeted mutagenesis in mouse models has revealed key roles for genes not anticipated to regulate gonadal development. Defining these molecular pathways provides the foundation for understanding this critical developmental event and provides new insight into the causes of gonadal dysgenesis.

T WAVE CONTOUR IN THE PRECORDIAL LEADS DURING CHILDHOOD

PEDIATRICS ◽  
1951 ◽  
Vol 7 (3) ◽  
pp. 400-407
Author(s):  
R. W. REYNOLDS
Keyword(s):  
Cardiovascular Disease ◽  
Young Adults ◽  
Cardiovascular System ◽  
Normal Children ◽  
Positive Wave ◽  
T Wave ◽  
Children And Young Adults ◽  
Transitional Forms ◽  
The Right ◽  
Age Range

The T wave in the precordial V leads was studied in 187 normal children and young adults in the age range of 2 weeks to 20 years and in 164 individuals of like age with cardiovascular disease or with disease or medication capable of affecting the cardiovascular system. On the basis of this analysis correlated with a survey of the literature, it is concluded that: a. An upright T wave in lead V2 or leads further to the right should be considered abnormal in children between 2 weeks and 9 years of age until proved otherwise. b. The normal sequence in the direction of the T wave from V4R to V6 is from a negative to a positive wave with transitional forms which may be notched or diphasic. The reversal of this pattern is to be considered abnormal. c. The presence of unexpected T wave contours in specific leads at the different ages should be considered as evidence demanding re-examination of the ECG and of the child for abnormalities.

Effectiveness of Therapy for the Treatment of Accommodative Insufficiency: An Open Pilot Study

2021 ◽  
pp. 270-278
Keyword(s):  
Young Adults ◽  
Limits Of Agreement ◽  
Convergence Insufficiency ◽  
Interclass Correlation ◽  
Children And Young Adults ◽  
Eligibility Requirements ◽  
Student’S T ◽  
The Right ◽  
Clinical Measures ◽  
Therapy Protocol

Background: To evaluate improvements in clinical measures and symptoms in children and young adults with accommodative insufficiency in an open trial of office-based vergence and accommodative therapy. Methods: Major eligibility requirements included ages 9 to 30 years and amplitude of accommodation (AA) ≥2 diopters (D) below Hoffstetter’s minimum. Participants completed 8 weekly, 1-hour sessions of office-based vergence and accommodative therapy. Therapy procedures followed the Convergence Insufficiency Treatment Trial (CITT) therapy protocol with emphasis on accommodative procedures. Clinical measures of accommodation and symptoms (Convergence Insufficiency Symptom Survey [CISS]) were assessed at baseline and after therapy. Results were evaluated using the Student’s t test and Kruskal-Wallis test. Repeatability of CISS scores at baseline was assessed using Bland Altman 95% Limits of Agreement (LoA) and Interclass Correlation Coefficient (ICC). Results: Eighteen participants (mean age 17.4 ± 8.0 years) were enrolled; sixteen completed the study. The mean AA improved significantly from 5.5D OD and OS at baseline to 12.4D OD and 12.8D OS at outcome (p<0.001). Mean monocular accommodative facility (AF) also increased significantly in both eyes from 6.6 cycles per min (cpm) OD and 7.4cpm OS at baseline to 14.2cpm OD and OS at outcome (p≤0.0009). Amplitude-scaled monocular AF also showed significant improvements (p≤0.034 for both). Mean CISS score improved 10.50 points (p=0.0003). Significantly greater improvements in AA were observed in children (9.0D) than in adults (4.3D) in the right eye (p=0.007 for both comparisons). Conversely mean improvement in CISS score was significantly greater in adults than in children (p=0.039). Repeated CISS scores differed by, on average,1.47 points (95% limits of agreement:-5.19, 8.13; p=0.12). The ICC was 0.95 with a 95% confidence interval of 0.87 to 0.98. Conclusion: Eight weekly sessions of office-based accommodative vergence therapy combined with homebased- reinforcement therapy resulted in improvements of symptoms and clinical measures of accommodation in children and young adults with accommodative insufficiency.

scholarly journals Effects of a Dynamic Chair on Chair Seat Motion and Trunk Muscle Activity during Office Tasks and Task Transitions

2018 ◽  
Vol 15 (12) ◽  
pp. 2723 ◽  
Author(s):  
Corina Nüesch ◽  
Jan-Niklas Kreppke ◽  
Annegret Mündermann ◽  
Lars Donath
Keyword(s):  
Young Adults ◽  
Muscle Activity ◽  
Muscle Activation ◽  
Dynamic Condition ◽  
Trunk Muscle ◽  
Erector Spinae ◽  
Task Transition ◽  
The Right ◽  
Hand Writing ◽  
And Task

Employing dynamic office chairs might increase the physical (micro-) activity during prolonged office sitting. We investigated whether a dynamic BioSwing® chair increases chair sway and alters trunk muscle activation. Twenty-six healthy young adults performed four office tasks (reading, calling, typing, hand writing) and transitions between these tasks while sitting on a dynamic and on a static office chair. For all task-transitions, chair sway was higher in the dynamic condition (p < 0.05). Muscle activation changes were small with lower mean activity of the left obliquus internus during hand writing (p = 0.07), lower mean activity of the right erector spinae during the task-transition calling to hand writing (p = 0.036), and higher mean activity of the left erector spinae during the task-transition reading to calling (p = 0.07) on the dynamic chair. These results indicate that an increased BioSwing® chair sway only selectively alters trunk muscle activation. Adjustments of chair properties (i.e., swinging elements, foot positioning) are recommended.

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