scholarly journals The Shape of Data: a Theory of the Representation of Information in the Cerebellar Cortex

2021 ◽  
Author(s):  
Mike Gilbert
Keyword(s):  
Cerebellar Cortex ◽  
Cell Group ◽  
Parallel Fibre ◽  
Circuit Input ◽  
Minimum Number ◽  
Fine Control ◽  
Group A ◽  
Rate Coding ◽  
Functional Equivalent ◽  
Mossy Fibres

AbstractThis paper presents a model of rate coding in the cerebellar cortex. The pathway of input to output of the cerebellum forms an anatomically repeating, functionally modular network, whose basic wiring is preserved across vertebrate taxa. Each network is bisected centrally by a functionally defined cell group, a microzone, which forms part of the cerebellar circuit. Input to a network may be from tens of thousands of concurrently active mossy fibres. The model claims to quantify the conversion of input rates into the code received by a microzone. Recoding on entry converts input rates into an internal code which is homogenised in the functional equivalent of an imaginary plane, occupied by the centrally positioned microzone. Homogenised means the code exists in any random sample of parallel fibre signals over a minimum number. The nature of the code and the regimented architecture of the cerebellar cortex mean that the threshold can be represented by space so that the threshold can be met by the physical dimensions of the Purkinje cell dendritic arbour and planar interneuron networks. As a result, the whole population of a microzone receives the same code. This is part of a mechanism which orchestrates functionally indivisible behaviour of the cerebellar circuit and is necessary for coordinated control of the output cells of the circuit. In this model, fine control of Purkinje cells is by input rates to the system and not by learning so that it is in conflict with the for-years-dominant supervised learning model.

Erythroid Homograft Following Leukocyte Transfusion in a Patient with Acute Leukemia

Blood ◽  
1965 ◽  
Vol 26 (5) ◽  
pp. 597-609 ◽  
Author(s):  
PAUL J. SCHMIDT ◽  
MITSUO YOKOYAMA ◽  
MARY H. MCGINNISS ◽  
ROBERT H. LEVIN
Keyword(s):  
Immune Response ◽  
Acute Leukemia ◽  
Gamma Globulin ◽  
Cell Mass ◽  
Myelogenous Leukemia ◽  
Cell Group ◽  
Red Cell ◽  
The Face ◽  
Group A ◽  
Antibody Levels

Abstract The establishment of a hematopoietic graft of stem cells from a donor with chronic myelogenous leukemia in a patient with acute leukemia took place in the face of ABO red cell group incompatibility. The donor was group A and the recipient who was group O gradually increased his red cell mass to become 80 per cent group A. There was both active and passive immunity to A present at the time of induction of the graft. The graft flourished despite persistent anti-A agglutinins and an immune response in the B agglutinin and hemolysin system. Failure of the graft coincided with a fall in antibody levels and was followed by a second immune response which included marked elevation of 7S gamma globulin levels. Red cell incompatibility was not a barrier to this graft and failure of the graft was probably due to other immune mechanisms.

Full Donor Chimerism in Both Plasma and Mononuclear Cell after Haematopoietic Stem Cell Transplant (HSCT) at D28 Is Predictive of Acute Graft-Versus-Host Disease but Not Disease Relapse or Graft Failure.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 5114-5114
Author(s):  
Shing Yan Ma ◽  
Wing Yan Au ◽  
Albert K.W. Lei ◽  
Eric Tse ◽  
Chor Sang Chim ◽  
...  
Keyword(s):  
Mononuclear Cell ◽  
Graft Rejection ◽  
Acute Gvhd ◽  
Haematopoietic Stem Cell ◽  
Cell Group ◽  
Disease Relapse ◽  
Donor Chimerism ◽  
Group A ◽  
Plasma Donor ◽  
Group B

Abstract Mononuclear cell mixed donor/recipient chimerism has been shown extensively to have high predictive value in disease relapse and graft rejection. Recently, donor DNA in plasma of transplant recipient has been suggested as a potential tool for post HSCT monitoring for disease relapse and graft rejection but its role has not been defined. Moreover, the impact of GVHD on plasma donor DNA remains unknown. In the current study, both the plasma and mononuclear cell donor chimerism of 40 patients post HSCT (mean age = 40; 35 myeloablative, 5 non-myeloablative) were analyzed at D28. Each patient was followed-up for one year or when disease relapse/graft rejection occurred. GVHD of grade II or above was also recorded to establish its correlation with the chimerism status. At D28, all patients were engrafted and alive. 5 (13%) patients had full donor chimerism in both plasma and mononuclear cell (Group A), 7 (18%) patients had full donor chimerism in the mononuclear cell only but not the plasma (Group B) and 28 (70%) patients failed to have full chimerism in both plasma and mononuclear cell (Group C). The sex, age, HLA-matching, donor relationship and ABO blood group matching had no impact on the chimerism status. None of the Group A patient had disease relapse/graft rejection at 1 year when compared to 13/35 (37%) of Group B and C patients (p=0.154, not significant).However, all the patients in Group A had acute GVHD which was significantly more than those in Group B and C (5/5 vs 12/35, p=0.009) and the acute GVHD would not alter the chimerism status. These results provide a foundation for further research on the potential role of plasma donor chimerism in predicting disease relapse/graft rejection and GVHD so that early intervention can be instituted.

Focal synaptic potentials due to discrete mossy-fibre arrival volleys in the cerebellar cortex

1987 ◽  
Vol 231 (1263) ◽  
pp. 217-230 ◽  
Keyword(s):  
Cerebellar Cortex ◽  
Granule Cells ◽  
Molecular Layer ◽  
Field Potential ◽  
Mossy Fibre ◽  
Synaptic Potential ◽  
Presynaptic Spike ◽  
Cell Firing ◽  
Mossy Fibres ◽  
Afferent Volleys

The previously described direct and relayed projections of periodontal afferents to the cerebellar cortex have been examined in detail by extracellular field-potential analysis. Advantage is taken of the very small temporal dispersion of the afferent volleys to permit identification of the presynaptic spike potential of mossy fibres, the subsequent synaptic potential and the firing of granule cells. Changes in form of the presynaptic potential with depth are compared with published descriptions of presynaptic potentials elsewhere. The negative synaptic potential in the granular layer is shown to have a positive aspect in the molecular layer. Granule-cell firing can, under some conditions, yield a population spike interrupting the synaptic potential wave. Records are presented showing all-or-none complex waves, which appear to be single glomerular potentials not previously described in the mammalian cerebellum. Their distinction from cellular spike potentials is emphasized.

scholarly journals Neurohistological changes in the cerebellar cortex of adult Wistar rats following lead acetate induced cortical damage

2021 ◽  
Vol 15 (3) ◽  
pp. 182-188
Author(s):  
Ajibade AJ ◽  
Ogundero SA
Keyword(s):  
Cerebellar Cortex ◽  
Lead Acetate ◽  
Wistar Rats ◽  
Histological Study ◽  
Control Group ◽  
Hair Dye ◽  
Study Results ◽  
Group A ◽  
The Mean ◽  
The Brain

This study investigated the neurohistological effect of lead acetate on cerebellar cortex of adult wistar rats. Lead is a common industrial poisonous substance that its prevalence in the environment exhibits toxic effect which makes different organs & tissues especially the central nervous system vulnerable to lead exposure. Lead is however, found useful applications in diverse items of daily needs like paints, water pipes, car batteries, leaded gasoline, ammunition, cosmetics, hair dye, airplanes, shielding for x-ray machines. Thirty-six (36) adult wistar rats of both sexes weighing between 120-250 grams were randomly grouped into four groups. Group A, B, C and D each group containing seven (9) rats. Group A rats served as the control, and was maintained on standard feed and water for 28 days, group B, C and D rats were treated orally once daily with 0.09g/kg, 0.18g/kg and 0.2g/kg of lead acetate respectively for 28 days. The weights of the wistar rats were recorded on weekly basis during the treatment. All the wistar rats in group A, B, C and D were sacrificed by cervical dislocation on the 29th day of the treatment. The brain was removed and weighed with a sensitive balance and the cerebellum of each rats was then fixed in 10% formol saline, the tissue was processed and stained with Hematoxylin and Eosin for histological study. Results showed that the mean body weights of the wistar rats significantly decreased in the treated groups when compared with the control group. The mean brain weights of the lead treated groups showed a significant decrease when compared to the control group. Histological study of the brain (cerebellar cortex) of the treated groups demonstrated degenerative changes revealed shrinkage, reduced sized and cellular loss of the Purkinje cells with vacuolations in the Purkinje cell layer compared with normal cerebellar histoarchitecture in the control. The study concluded that lead acetate has a neurotoxic effect on the cerebellar cortex of adult wistar rats which may ultimately impair some cerebellar functions.

scholarly journals A comparative study to determine the role of pre and post-operative antibiotic therapy versus only pre-operative antibiotic therapy in patients of non-perforated acute appendicitis

2020 ◽  
Vol 7 (10) ◽  
pp. 3305
Author(s):  
Goutam K. Chowdegowda ◽  
Satya V. Arya ◽  
Ashok K. Sharma ◽  
Dheer Singh Kalwaniya ◽  
Jaspreet Singh Bajwa
Keyword(s):  
Acute Appendicitis ◽  
Antibiotic Therapy ◽  
P Value ◽  
New Delhi ◽  
Medical College ◽  
The People ◽  
Minimum Number ◽  
Group A ◽  
The Mean ◽  
Group B

Background: If properly used in appendicitis, antibiotics can reduce the rate of infection by 50%. The use of post-operative antibiotics for preventing infective complications in non-perforated cases is still controversial.Methods: A randomised prospective study was conducted in the Department of Surgery, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi with patients who presented acute appendicitis. A minimum number of 30 patients each in group A (pre-operative and post-operative antibiotics) and group B (only pre-operative antibiotics) were evaluated for 18 months, from January 2018 to June 2019.Results: The mean age of group A is 29.9±15.16 years and in group B is 25.97±9.470 years (p value=0.122, insignificant). There was male preponderance. The seroma formation in both the groups was 10.00% and no patients developed intra-abdominal abscess. The incidence of local site oedema was 10% in both the groups A and B and their p value is insignificant. In both the groups A and B, 10% of the people developed pus discharge from the stitch line and the p value is insignificant. In group A, 6.67% of the patients and in group B 10.00% of the patients developed stitch line inflammatory changes and the p value insignificant. In group A, 13.3% and in group B, 10.00% of the patients developed fever and their p value is 1. The mean length of hospital in case 1.23±0.5 days (group A) and is 1.17±0.45 days (group B) (p value=0.508).Conclusions: Hence we can conclude that a well-chosen and adequately-timed pre-operative antibiotics are adequate in preventing post-operative complications and post-operative antibiotics do not affect the same.

Presenting Features Predictive of Long-Term Stability in Chronic Lymphocytic Leukemia.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 4982-4982
Author(s):  
Kortney L. Hillier ◽  
Sarah S. Fung ◽  
Linda M. Vickars ◽  
Chantal S. Leger ◽  
Paul F. Galbraith ◽  
...  
Keyword(s):  
B Cell ◽  
Lymphocyte Count ◽  
Lymphocytic Leukemia ◽  
Cell Group ◽  
Term Stability ◽  
Long Term Stability ◽  
Group A ◽  
Group B

Abstract Prognostic factors to predict an aggressive clinical course in chronic lymphocytic leukemia (CLL) such as CD38, ZAP-70 and IgH mutation status have been well described, however, readily available presenting features predictive of long-term stability are less well defined. We performed a retrospective analysis of 335 consecutive patients with CLL seen at St. Paul’s Hospital from January 1969 to July 2005. Patients were identified from the practice data-base and clinical and pathological data abstracted by chart review. Long-term stability was defined as no requirement for treatment for at least 6 years (n=66, group A). Characteristics of group A were compared to all other pts (group B, n=269), and, to avoid follow-up bias, to pts followed for ≥6 y who required treatment (group C, n=62). 65 pts in group A were B-cell in phenotype and 1 was T-cell; group B 268 pts B-cell, 1 T-cell; group C all 62 B-cell. Median age at diagnosis for groups A, B and C were 59.5 (range 33–80) y; 68 (30–94) y; and 60 (30–82) y, respectively (p<0.0001 for A vs. B and p<0.42 for A vs. C). Male pts comprised 52%, 54.3% and 53% of groups A, B and C respectively (p<0.85). Rai stages were: stage 0, 1, 2, 3, and 4; 111, 48, 47, 3 and 6 respectively. ECOG Performance Status was 0 in 307 pts and was not analyzed further. Lymphocyte count at diagnosis (LCD) for groups A, B and C were 9 (4–50 X 109/L), 10 (3–394) and 12 (3–155; p<0.0001 for A vs. B and p< 0.01 for A vs. C); in group A, 25 (38%) of pts had a LCD ≤10, as did 81 (30%) in group B and 10 (16%) in group C. In groups A, B and C, 9 (13.6%), 21 (11.5%), and 7 (11.3%) pts, respectively, had a lymphocyte doubling time (LDT) ≤12mo (to an absolute value ≥50X109/L; p<0.65). Immunophenotyping was available in 202 pts; 173 were CD5+ CD19+, 2 were CD5- and 29 CD19-. Analysis for CD38 was available in 50 pts; in groups A, B and C, 5 of 36 (14.3%), 2 of 14 (16.7%) and 0 of 7, respectively, were CD38+ (defined as ≥30% of cells; p<0.84). Median follow-up for groups A, B and C was 110.5 (76–369) mo, 43 (0–309) mo, and 134.5 (72–309 mo; p<0.0001 for A vs. B and p<0.67 for A vs. C). Pts in group A did not require treatment by definition; time to treatment (TTT) for group B was median 35 (0–243) mo and group C 66 (0–243) mo (p<0.0001). Median OS for all pts was 191 (0–369) mo. Two deaths occurred in group A; 1 of Richter’s transformation at 77 mo and 1 of unknown causes at 78 mo; median OS for groups B and C was 189 (0–311) mo and 127 (69–311) mo respectively (p<0.025). In group A, 1 pt (1.5%) transformed, as did 15 (5.6%) in group B (8 Richter’s and 7 PLL) and 4 (6%) in group C (1 Richter’s, 3 PLL, p<0.46). At a cutoff in LCD of 10 and 20 the difference in OS between groups was maintained (see Table). Characteristic OS @ 120 mo (%) Lymphocyte count at Dx (X109/L) Group A (stable ≥ 72 mo, n=66) Group B (all others, n=269) Group C (not stable, ≥72 f/u mo, n=62) All pts 93 64 64 ≤10 100 100 100 >10 91 64 64 ≤20 93 38 38 >20 0 of 2 0 of 5 0 of 5 p (log rank) A vs. B p<0.023 A vs. C p<0.025 In conclusion, in this series of 335 patients with CLL, lower lymphocyte count at diagnosis predicted for long-term stability, decreased requirement for treatment and improved OS.

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