scholarly journals Segment number threshold determines juvenile onset of germline cluster expansion in Platynereis dumerilii

2021 ◽  
Author(s):  
Emily Kuehn ◽  
David S. Clausen ◽  
Ryan W. Null ◽  
Bria M. Metzger ◽  
Amy D. Willis ◽  
...  
Keyword(s):  
Cluster Expansion ◽  
Juvenile Onset ◽  
Segment Number ◽  
Platynereis Dumerilii

scholarly journals Segment number threshold determines juvenile onset of germline cluster proliferation in Platynereis dumerilii

2021 ◽  
Author(s):  
Emily Kuehn ◽  
David S Clausen ◽  
Ryan W Null ◽  
Bria M Metzger ◽  
Amy D Willis ◽  
...  
Keyword(s):  
Germ Cell ◽  
Developmental Stages ◽  
Primordial Germ Cells ◽  
The Body ◽  
Germline Development ◽  
Growth State ◽  
Cell Clusters ◽  
Segment Number ◽  
Platynereis Dumerilii ◽  
Tightly Coupled

Many animals rely on sexual reproduction to propagate by using gametes (oocytes and sperm). Development of sexual characters and generation of gametes are tightly coupled with the growth of an organism. Platynereis dumerilii is a marine segmented worm which has been used to study germline development and gametogenesis. Platynereis has 4 Primordial Germ Cells (PGCs) that arise early in development and these cells are thought to give rise to germ cell clusters found across the body in the juvenile worms. The germ cell clusters eventually form the gametes. The stages of germline development and how the 4 PGCs become the numerous germ cell clusters are not well-documented in the juvenile stages. Platynereis, like other segmented worms, grows by adding new segments at its posterior end. The number of segments generally reflect the growth state of the worms and therefore is a useful and easily measurable growth state metric. To understand how growth correlates with development and gametogenesis, we investigated germline development across several developmental stages using germline/multipotency markers. We found that segment number predicted the state of germline development and the abundance of germline clusters. Additionally, we found that keeping worms short in segment number via changing external conditions or via amputations supported segment number threshold requirement for germline development. Finally, we asked if these clusters in Platynereis play a role in regeneration (as similar free-roaming cells are observed in Hydra and planarian regeneration) and found that the clusters were not required for regeneration in Platynereis, suggesting a strictly germline nature. Overall, these molecular analyses suggest a previously unidentified developmental transition dependent on the growth state in juvenile Platynereis when germline proliferation is substantially increased.

Retinopathy in juvenile-onset type I diabetes of short duration

Diabetes ◽  
1982 ◽  
Vol 31 (10) ◽  
pp. 874-882 ◽  
Author(s):  
R. N. Frank ◽  
W. H. Hoffman ◽  
M. J. Podgor ◽  
H. C. Joondeph ◽  
R. A. Lewis ◽  
...  
Keyword(s):  
Short Duration ◽  
Type I Diabetes ◽  
Type I ◽  
Juvenile Onset ◽  
Onset Type

Bone impairment assessed by HR-pQCT in juvenile-onset systemic lupus erythematosus

2015 ◽  
Vol 27 (5) ◽  
pp. 1839-1848 ◽  
Author(s):  
J. A. Paupitz ◽  
G. L. Lima ◽  
J. C. Alvarenga ◽  
R. M. Oliveira ◽  
E. Bonfa ◽  
...  
Keyword(s):  
Systemic Lupus Erythematosus ◽  
Lupus Erythematosus ◽  
Systemic Lupus ◽  
Juvenile Onset ◽  
Onset Systemic Lupus Erythematosus

scholarly journals One repeated transplantation of allogeneic umbilical cord mesenchymal stromal cells in type 1 diabetes: an open parallel controlled clinical study

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jing Lu ◽  
Shan-mei Shen ◽  
Qing Ling ◽  
Bin Wang ◽  
Li-rong Li ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Stromal Cells ◽  
Treated Group ◽  
Control Group ◽  
Adult Onset ◽  
Β Cell ◽  
Juvenile Onset ◽  
C Peptide

Abstract Background The preservation or restoration of β cell function in type 1 diabetes (T1D) remains as an attractive and challengeable therapeutic target. Mesenchymal stromal cells (MSCs) are multipotent cells with high capacity of immunoregulation, which emerged as a promising cell-based therapy for many immune disorders. The objective of this study was to examine the efficacy and safety of one repeated transplantation of allogeneic MSCs in individuals with T1D. Methods This was a nonrandomized, open-label, parallel-armed prospective study. MSCs were isolated from umbilical cord (UC) of healthy donors. Fifty-three participants including 33 adult-onset (≥ 18 years) and 20 juvenile-onset T1D were enrolled. Twenty-seven subjects (MSC-treated group) received an initial systemic infusion of allogeneic UC-MSCs, followed by a repeat course at 3 months, whereas the control group (n = 26) only received standard care based on intensive insulin therapy. Data at 1-year follow-up was reported in this study. The primary endpoint was clinical remission defined as a 10% increase from baseline in the level of fasting and/or postprandial C-peptide. The secondary endpoints included side effects, serum levels of HbA1c, changes in fasting and postprandial C-peptide, and daily insulin doses. Results After 1-year follow-up, 40.7% subjects in MSC-treated group achieved the primary endpoint, significantly higher than that in the control arm. Three subjects in MSC-treated group, in contrast to none in control group, achieved insulin independence and maintained insulin free for 3 to 12 months. Among the adult-onset T1D, the percent change of postprandial C-peptide was significantly increased in MSC-treated group than in the control group. However, changes in fasting or postprandial C-peptide were not significantly different between groups among the juvenile-onset T1D. Multivariable logistic regression assay indicated that lower fasting C-peptide and higher dose of UC-MSC correlated with achievement of clinical remission after transplantation. No severe side effects were observed. Conclusion One repeated intravenous dose of allogeneic UC-MSCs is safe in people with recent-onset T1D and may result in better islet β cell preservation during the first year after diagnosis compared to standard treatment alone. Trial registration ChiCTR2100045434. Registered on April 15, 2021—retrospectively registered, http://www.chictr.org.cn/

scholarly journals Cerebrotendinous Xanthomatosis: diversity of presentation and refining treatment with chenodeoxycholic acid

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Mahjabin Islam ◽  
Nigel Hoggard ◽  
Marios Hadjivassiliou
Keyword(s):  
Chenodeoxycholic Acid ◽  
Clinical Characteristics ◽  
Spastic Paraparesis ◽  
Acid Synthesis ◽  
Bile Acid Synthesis ◽  
Cerebrotendinous Xanthomatosis ◽  
Juvenile Onset ◽  
Progressive Ataxia ◽  
Classical Triad ◽  
High Index Of Suspicion

Abstract Background Cerebrotendinous xanthomatosis (CTX) is a rare but treatable neurometabolic disorder of lipid storage and bile acid synthesis. Whilst CTX is said to present with the classic triad of juvenile onset cataracts, tendon xanthomata and progressive ataxia, the diversity of presentation can be such that the diagnosis may be substantially delayed resulting in permanent neurological disability. Methods A retrospective review of the clinical characteristics and imaging findings of 4 patients with CTX presenting to the Sheffield Ataxia Centre over a period of 25 years. Results Although CTX-related symptoms were present from childhood, the median age at diagnosis was 39 years. Only 1 of the 4 cases had tendon xanthomata, only 2 cases had juvenile onset cataracts and 3 had progressive ataxia with one patient presenting with spastic paraparesis. Serum cholestanol was elevated in all 4 patients, proving to be a reliable diagnostic tool. In addition, cholestanol was raised in the CSF of 2 patients who underwent lumbar puncture. Despite treatment with chenodeoxycholic acid (CDCA) and normalization of serum cholestanol, CSF cholestanol remained high in one patient, necessitating increase in the dose of CDCA. Further adjustments to the dose of CDCA in the patient with raised CSF cholestanol resulted in slowing of progression. Two of the patients who have had the disease for the longest continued to progress, one subsequently dying from pneumonia. Conclusion A high index of suspicion for CTX, even in the absence of the classical triad is essential in reaching such diagnosis. The earlier the diagnosis and treatment, the better the outcome.

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