► I investigate the effect of self gravity on orbital evolution of Twotinos. ► I show the timescale in which the half of Twotinos becomes unstable. ► I find the total mass of Twotinos can be reduced ...significantly by the self gravity.
We investigate how the self gravity of Twotinos changes its orbital stability using N-body simulations in which the gravitational interaction between planetesimals are fully calculated. We show the timescale in which the half of Twotinos becomes unstable,
t
half
, obey the formula,
t
half
=
4
×
10
6
M
tot
0.1
M
⊕
-
1
m
p
7.6
×
10
23
g
-
1
〈
i
2
〉
1
/
2
0.002
(
years
)
,
if we assume the primordial planetesimals disk have the power low surface mass density,
Σ
=
Σ
0
×
r
−2/3. Where
M
tot
,
m
p
, 〈
i
2〉
1/2 are the total mass of large bodies of Twotinos, the maximum mass of planetesimals, and the inclination dispersion. With this formulae, we conclude the total mass of Twotinos is reduced to the order of 0.01
M
⊕ by the self gravity and secular perturbation of Planets even if there was huge mass such as several order of the Earth mass in 1:2 MMR of Neptune at the early age of the Solar System. These results will invoke reexamination to many previous works explaining the dynamical evolution of TNOs.
Definition and classification of chronic kidney disease: A position statement from Kidney Disease: Improving Global Outcomes (KDIGO). Chronic kidney disease (CKD) is a worldwide public health ...problem, with adverse outcomes of kidney failure, cardiovascular disease (CVD), and premature death. A simple definition and classification of kidney disease is necessary for international development and implementation of clinical practice guidelines. Kidney Disease: Improving Global Outcomes (KDIGO) conducted a survey and sponsored a controversies conference to (1) provide a clear understanding to both the nephrology and nonnephrology communities of the evidence base for the definition and classification recommended by Kidney Disease Quality Outcome Initiative (K/DOQI), (2) develop global consensus for the adoption of a simple definition and classification system, and (3) identify a collaborative research agenda and plan that would improve the evidence base and facilitate implementation of the definition and classification of CKD.
The K/DOQI definition and classification were accepted, with clarifications. CKD is defined as kidney damage or glomerular filtration rate (GFR) <60 mL/min/1.73 m2 for 3 months or more, irrespective of cause. Kidney damage in many kidney diseases can be ascertained by the presence of albuminuria, defined as albumin-to-creatinine ratio >30 mg/g in two of three spot urine specimens. GFR can be estimated from calibrated serum creatinine and estimating equations, such as the Modification of Diet in Renal Disease (MDRD) Study equation or the Cockcroft-Gault formula. Kidney disease severity is classified into five stages according to the level of GFR. Kidney disease treatment by dialysis and transplantation should be noted. Simple, uniform classifications of CKD by cause and by risks for kidney disease progression and CVD should be developed.
Insect feeding behavior is regulated by many intrinsic factors, including hemolymph nutrient levels. Adipokinetic hormone (AKH) is a peptide factor that modulates hemolymph nutrient levels and ...regulates the nutritional state of insects by triggering the transfer of lipids into the hemolymph. We recently demonstrated that RNA interference (RNAi)-mediated knockdown of the AKH receptor (AKHR) reduces hemolymph lipid levels, causing an increase in the feeding frequency of the two-spotted cricket, Gryllus bimaculatus. This result indicated that reduced hemolymph lipid levels might motivate crickets to feed. In the present study, to elucidate whether hemolymph lipid levels contribute to insect feeding behavior, we attempted to manipulate hemolymph lipid levels via the lipophorin (Lp)-mediated lipid transferring system in G. bimaculatus. Of the constituent proteins in Lp, we focused on apolipophorin-III (GrybiApoLp-III) because of its possible role in facilitating lipid mobilization. First, we used RNAi to reduce the expression of GrybiApoLp-III. RNAi-mediated knockdown of GrybiApoLp-III had little effect on basal hemolymph lipid levels and the amount of food intake. In addition, hemolymph lipid levels remained static even after injecting AKH into GrybiApoLp-IIIRNAi crickets. These observations indicated that ApoLp-III does not maintain basal hemolymph lipid levels in crickets fed ad libitum, but is necessary for mobilizing lipid transfer into the hemolymph following AKH stimulation. Second, Lp (containing lipids) was injected into the hemolymph to induce a temporary increase in hemolymph lipid levels. Consequently, the initiation of feeding was delayed in a dose-dependent manner, indicating that increased hemolymph lipid levels reduced the motivation to feed. Taken together, these data validate the importance of basal hemolymph lipid levels in the control of energy homeostasis and for regulating feeding behavior in crickets.
A novel type of crystalline organic-inorganic hybrid microporous silicate material, KCS-5, was synthesized supposedly from a lamellar precursor composed of amphiphilic organosilicic acids. This ...well-ordered material has a crystalline structure, is thermally stable up to 500 °C and has lipophilic 1-dimensional micropores.
Multisystem inflammatory syndrome in adults (MIS-A) is a life-threatening disease that can develop weeks after coronavirus disease 2019 (COVID-19). MIS-A symptoms include multiorgan involvement, ...especially gastrointestinal tract and heart involvement, and Kawasaki disease-like symptoms. We herein report a 44-year-old Japanese man with MIS-A who had contracted COVID-19 five weeks ago and went into shock after acute gastroenteritis, acute kidney injury, and Kawasaki disease-like symptoms. Methylprednisone pulse and high-dose intravenous immunoglobulin resulted in recovery of shock and his renal function, but diffuse ST-segment elevation on electrocardiography and pericardial effusion with a fever emerged after therapy. Additional granulocyte-monocyte adsorptive apheresis successfully ameliorated the cardiac involvement.
With the worldwide spread of the COVID-19 vaccine program during the COVID-19 pandemic, the numbers of reported cases with new-onset or relapsed kidney disease/vasculitis such as minimal change ...nephrotic syndrome, immunoglobulinA (IgA) nephropathy, and IgA vasculitis (IgAV) that developed after COVID-19 vaccination are increasing. We present the case of a 67-year-old Japanese woman who developed IgAV with purpura on her extremities and trunk in the evening of the day that she received the second dose of the Pfizer-BioNTech COVID-19 vaccine. She subsequently presented with acute kidney injury and nephrotic syndrome, and a kidney biopsy performed 14 days after the second vaccination showed diffuse mesangial and endocapillary glomerulonephritis with necrotizing crescent formation, accompanied by IgA deposition. One steroid pulse plus four administrations of a monthly intravenous cyclophosphamide injection were applied, followed by oral azathioprine during oral steroid tapering. Her response to this treatment was unsatisfactory and intractable for some time. Eventually, her renal function improved and nephrotic syndrome was resolved, while microscopic hematuria and proteinuria at ~ 1 g/gCr remained at 6 months post-vaccination. Unlike the previous milder renal-involved IgAV cases following COVID-19 vaccination, our patient’s case presented severe glomerulonephritis and took a long time to recover despite intensive initial immunosuppressive treatment.
Accurate estimation of the glomerular filtration rate (GFR) is crucial for the detection of chronic kidney disease (CKD). In clinical practice, GFR is estimated from serum creatinine using the ...Modification of Diet in Renal Disease (MDRD) study equation or the Cockcroft-Gault (CG) equation instead of the time-consuming method of measured clearance for exogenous markers such as inulin. In the present study, the equations originally developed for a Caucasian population were tested in Japanese CKD patients, and modified with the Japanese coefficient determined by the data.
The abbreviated MDRD study and CG equations were tested in 248 Japanese CKD patients and compared with measured inulin clearance (Cin) and estimated GFR (eGFR). The Japanese coefficient was determined by minimizing the sum of squared errors between eGFR and Cin. Serum creatinine values of the enzyme method in the present study were calibrated to values of the noncompensated Jaffé method by adding 0.207 mg/dl, because the original MDRD study equation was determined by the data for serum creatinine values measured by the noncompensated Jaffé method. The abbreviated MDRD study equation modified with the Japanese coefficient was validated in another set of 269 CKD patients.
There was a significant discrepancy between measured Cin and eGFR by the 1.0xMDRD or CG equations. The MDRD study equation modified with the Japanese coefficient (0.881xMDRD) determined for Japanese CKD patients yielded lower mean difference and higher accuracy for GFR estimation. In particular, in Cin 30-59 ml/min per 1.73 m(2), the mean difference was significantly smaller with the 0.881xMDRD equation than that with the 1.0xMDRD study equation (1.9 vs 7.9 ml/min per 1.73 m(2); P < 0.01), and the accuracy was significantly higher, with 60% vs 39% of the points deviating within 15%, and 97% vs 87% of points within 50%, respectively (both P < 0.01). Validation with the different data set showed the correlation between eGFR and Cin was better with the 0.881xMDRD equation than with the 1.0xMDRD study equation. In Cin less than 60 ml/min per 1.73 m(2), the accuracy was significantly higher, with 85% vs 69% of the points deviating within 50% (P < 0.01), respectively. The mean difference was also significantly smaller (P < 0.01). However, GFR values calculated by the 0.881xMDRD equation were still underestimated in the range of Cin over 60 ml/min per 1.73 m(2).
Although the Japanese coefficient improves the accuracy of GFR estimation of the original MDRD study equation, a new equation is needed for more accurate estimation of GFR in Japanese patients with CKD stages 3 and 4.
Abstract
Background
Patients on haemodialysis are predisposed to heart rhythm disorders, including bradyarrhythmia, atrial fibrillation (AF)/atrial flutter, supraventricular/ventricular arrhythmias ...and sudden cardiac death (SCD) (Turakhia et al. in Eur Heart J 39:2314–2325, 2018). In addition to the fact that patients on haemodialysis have a high prevalence of underlying cardiac disease, the stress of haemodialysis itself might also contribute to increased rates of arrhythmias and SCD (Samanta et al. in Can J Cardiol 35:1228–1240, 2019).
Methods
A Holter 24-h electrocardiogram was set up immediately before the start of haemodialysis for 72 haemodialysis patients (dialysis vintage: 6–8734 days) to record premature ventricular contractions (PVCs) as a marker of arrhythmogenesis for 24 h. Blood samples were also collected every hour during haemodialysis treatment. Each patient was dialyzed against a dialysate consisting of Na
+
140 mEq/L, K
+
2.0 mEq/L, Ca
+
3.0 mEq/L, Mg
2+
1.0 mEq/L, Cl
−
110 mEq/L, CH
3
COO
−
8 mmol/L and HCO
3
−
30 mEq/L.
Results
The frequency of PVCs significantly increased in the 4th (80 ± 34 beats/hour, mean ± S.E.), 5th (79 ± 31 beats/hour) and 6th (105 ± 36 beats/hour) hours (
F
= 5.24,
p
< 0.00001,
n
= 72). The lowest left ventricular ejection fraction (LVEF,
p
= 0.001) and the highest b-type natriuretic peptide (BNP) levels (
p
= 0.049) were found in patients with the highest PVC counts. There was an association of positive changes in both serum K
+
(β ± S.E., 9.7 ± 2.4,
p
= 0.0002), Mg
2+
(43.2 ± 10.3,
p
= 0.0001) and HCO
3
−
(5.3 ± 1.8,
p
= 0.005) with the frequency of PVCs for 4 h immediately after dialysis. During the same period, there was an association of lower serum K
+
(− 8.37 ± 2.16,
p
= 0.0003) and higher Ca
2+
(73.4 ± 18.0,
p
= 0.0002) with the frequency of PVCs.
Conclusions
Haemodialysis stimulated PVC generation, and this effect was especially prominent during the period immediately after haemodialysis. Some serum electrolyte changes affected this PVC stimulation. A positive change in serum K
+
or Mg
2+
and a negative change in serum Ca
2+
during dialysis are risk factors for stimulating PVCs, particularly in patients with lower serum K
+
or higher serum Ca
2+
levels at the start of dialysis.
The number of patients with end-stage renal disease (ESRD) in Japan has continuously increased in the past three decades. In 2005, 36,063 patients whose average age was 66 years entered a new ...dialysis program. This large number of ESRD patients could be just the tip of the iceberg of an increasing number of patients with chronic kidney disease (CKD). However, to date, a nationwide epidemiological study has not been conducted yet to survey the CKD population.
Data for 527,594 (male, 211,034; female, 316,560) participants were obtained from the general adult population aged over 20 years who received annual health check programs in 2000-2004, from seven different prefectures in Japan: Hokkaido, Fukushima, Ibaraki, Tokyo, Osaka, Fukuoka, and Okinawa prefectures. The glomerular filtration rate (GFR) for each participant was estimated from the serum creatinine values, using the abbreviated Modification of Diet in Renal Disease (MDRD) study equation modified by the Japanese coefficient.
The prevalences of CKD stage 3 in the study population, stratified by age groups of 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, and 80-89 years, were 1.4%, 3.6%, 10.8%, 15.9%, 31.8%, 44.0%, and 59.1%, respectively, predicting 19.1 million patients with stage 3 CKD in the Japanese general adult population of 103.2 million in 2004. CKD stage 4 + 5 was predicted in 200,000 patients in the Japanese general adult population. Comorbidity of hypertension, diabetes, and proteinuria increased as the estimated GFR (eGFR) decreased. The prevalence of concurrent CKD was significantly higher in hypertensive and diabetic populations than in the study population overall when CKD was defined as being present with an eGFR of less than 40 ml/min per 1.73 m(2) instead of less than 60 ml/min per 1.73 m(2).
About 20% of the Japanese adult population (i.e., approximately 19 million people) are predicted to have stage 3 to 5 CKD, as defined by a GFR of less than 60 ml/min per 1.73 m(2).
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