Osteoblastogenesis regulation signals in bone remodeling

Bone remodeling is essential for adult bone homeostasis. The failure of this process often leads to the development of osteoporosis, a present major global health concern. The most important factor that affects normal bone remodeling is the tightly controlled and orchestrated regulation of osteoblasts and osteoclasts. The present review summarized the recent discoveries related to osteoblast regulation from several signals, including transforming growth factor-β, bone morphogenetic proteins, Wnt signal, Notch, Eph-Ephrin interaction, parathyroid hormone/parathyroid hormone-related peptide, and the leptin-serotonin-sympathetic nervous systemic pathway. The awareness of these mechanisms will facilitate further research that explores bone remodeling and osteoporosis. Future investigations on the endogenous regulation of osteoblastogenesis will increase the current knowledge required for the development of potential drug targets in the treatment of osteoporosis.

Potential heating effect in the gravid uterus during MR HASTE imaging

Our purpose was to evaluate if temperature changes occur in maternal or fetal tissues during HASTE imaging.

METHODS

Pregnant pigs were scanned with the HASTE technique, and temperatures were measured with phase maps and temperature probes inserted into the amniotic fluid and fetal brain.

RESULTS

Fiberoptic probes showed that no heating occurred in fetal tissues or amniotic fluid during HASTE imaging.

CONCLUSION

Our current HASTE protocols do not deposit a significant amount of heat in the gravid uterus. J. Magn. Reson. Imaging 2001;13:856-861.

Research note: sleep problems of normal Chinese adolescents

Eight hundred and forty-six Chinese adolescents were surveyed concerning sleep behaviours including insomnia, nightmares, somniloquism, somnambulism, bruxism, and enuresis. Bruxism was reported most frequently (22%) followed by somniloquism (17%) and insomnia (14.9%). Subjects were compared by sex, age, and rearing by parents or parent surrogates. Cross cultural comparisons and the possible significance of findings are discussed.

In vivo bone marrow lipid characterization with line scan Carr-Purcell-Meiboom-Gill proton spectroscopic imaging

Line scan Carr-Purcell-Meiboom-Gill spectroscopic imaging sequences have been used to extract lipid chemical composition indices in healthy adult bone marrow in the knee at 1.5 T. Since several spectroscopic echo readouts follow each excitation, the information acquired reflects a balance between spectral T2 decay processes and spectral resolution. To examine this balance in detail, data sets with two different echo spacings and spectral resolutions have been acquired to compare the information available from each in studies of bone marrow. Oils for which high field (7 T) proton spectra were recorded were used to evaluate the accuracy of lipid chemical composition indices extracted from the line scan Carr-Purcell-Meiboom-Gill spectroscopic imaging methods at 1.5 T. The extension of the method to fast spectroscopic imaging of bone marrow with multiple echoes is demonstrated.

Characterization of hydroxyapatite film with mixed interface by Ar+ ion beam enhanced deposition

Ar+ ion beam enhanced deposition (IBED) was used to produce a hydroxyapatite (HA) film on polished titanium substrates. In this study, the HA ceramic target was sputtered by an argon-ion beam with an energy of 1.5 KeV, and the sputtered film was intermittently bombarded by energetic argon-ions at 60 KeV. An effective Ca-Ti mixed layer produced by the energetic argon-ion bombardment was confirmed by using Auger electron spectroscopy. The characteristics of the deposited films were evaluated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. XRD analysis revealed that the as-deposited film was amorphous, and a hydroxyapatite-type structure was obtained from the post-heat treatment of the deposited films. SEM observations showed that no distinct difference in surface morphology was found between the as-deposited and heat-treated samples for Ar+ IBED films, suggesting a strongly bonded HA film on the titanium substrate. In comparison with the HA target, some chemistry alterations were brought about in the deposited films, such as the incorporation of CO3, the loss of the OH groups and some distortion of the phosphate lattice.

Chronic sun exposure is associated with distinct histone acetylation changes in human skin

BACKGROUND

Photoageing is attributed to continuous sunlight or artificial ultraviolet exposure and manifests as clinical and histological changes in skin. Epigenetic changes have been found to be involved in the pathogenesis of photoageing. However, the underlying mechanisms are unclear.

OBJECTIVES

To analyse histone modification patterns in sun-exposed and nonexposed skin, and to identify the abnormally histone-modified genes related to photoageing.

METHODS

Skin biopsies were collected from both the outer forearm (sun-exposed area) and the buttock (sun-protected area) in 20 healthy middle-aged female volunteers. Global histone H3/H4 acetylation and H3K4/H3K9 methylation statuses were assessed by enzyme-linked immunosorbent assay. Expression levels of histone acetyltransferases and histone deacetylases were measured by reverse-transcriptase quantitative polymerase chain reaction (qPCR) and Western blot. Chromatin immunoprecipitation combined with DNA microarray (ChIP-chip) assay with anti-acetyl-histone H3 antibody in a sun-exposed pool (combining six sun-exposed skin samples) and a nonexposed pool (combining six nonexposed skin samples) was conducted to explore the abnormally acetylated histone H3 genes related to photoageing; ChIP-qPCR was then used to verify the results of ChIP-chip.

RESULTS

We observed higher global histone H3 acetylation levels increased EP300 and decreased HDAC1 and SIRT1 expression in sun-exposed skin compared with matched nonexposed skin. Furthermore, the ChIP-chip assay showed that 227 genes displayed significant hyperacetylation of histone H3, and 81 genes displayed significant hypoacetylation of histone H3 between the two groups. Histone H3 acetylation levels on the promoters of PDCD5, ITIH5, MMP1 and AHR were positively correlated with the mRNA expression of the corresponding gene.

CONCLUSIONS

Chronic sun exposure-induced histone H3 hyperacetylation may play a critical role in the pathogenesis of skin photoageing.

FDG-PET study of the bilateral subthalamic nucleus stimulation effects on the regional cerebral metabolism in advanced Parkinson disease

The aim of the study was to evaluate the changes in regional cerebral metabolic rate of glucose (rCMRGlu) induced by bilateral subthalamic nucleurs (STN) stimulation in advanced Parkinson's disease (PD). 18F-Fluorodeoxyglucose (FDG) PET data obtained before and one month after stimulation were analyzed with statistical parametric mapping (SPM). As a result of clinically effective bilateral STN stimulation, rCMRGlu increased in lateral globus pallidus (GP), upper brain stem, dorsolateral prefrontal cortex (DLPFC) and posterior parietal-occipital cortex, and decreased in the orbital frontal cortex and parahippocampus gyrus (p < 0.001). We conclude that the alleviation of clinical symptoms in advanced PD by bilateral STN stimulation may be the result of activation of both ascending and descending pathways from STN and of restoration of the impaired higher-order cortex functions.

Trial of antiepilepsirine (AES) in children with epilepsy

Antieplepsirine (AES) is a new antiepileptic drug (AED) which was originally extracted from a Chinese folk remedy, and is now chemically characterized and synthesized. Its chemical structure is different from those of other available AEDs. Animal experiments involving AES demonstrated significant antiepileptic activity. Only a few clinical studies of AES with open trial have been resorted, none of which were on children. A 6.5 month, add-on, double-blind, placebo-controlled, randomized, cross-over study on AES (10 mg/kg per day) was conducted on epileptic children (aged 1-14 years) refractory to treatment with standard AEDs. The seizure frequency was recorded, and the blood levels of AES and other co-medicated AEDs (phenobarbital, phenytoin, carbamazepine and valproate) were determined. Although not planned, patients or parents were allowed to refuse to cross-over to the alternate therapy. The results were compared to the children who crossed-over as well as for the entire group during the first 3 months of randomized treatment. A total of 58 children entered, but only 34/58 children completed the cross-over study. The 24 children whose parents refused to let them be crossed-over continued the original study treatment (AES or placebo) for the entire 6 months. There was no statistically significant difference in seizure control when the entire group of 58 patients was compared to a parallel study group for the first 3 months of therapy (P = 0.178). There was a significant difference (P<0.01) in seizure control between AES and placebo treatment for the 34 patients who completed the entire cross-over study. No significant changes were seen in the blood level of other AEDs, and no serious acute side effects were observed. The results of the present study indicate the efficacy of AES for epileptic children with refractory seizures.

Patterns of psychiatric consultation in a Chinese general hospital

The authors conducted a study of psychiatric consultation in a Chinese general hospital. Seventy-five inpatients (0.74% of the patients in the hospital) were referred by different services over a 1-year period. Internal medicine referred the most patients, and organic brain syndromes were the most common diagnoses. Depression was not a frequent diagnosis, but neurasthenia was a fairly common one. None of the referred patients had a diagnosis of alcoholism, drug abuse, or personality disorder. The authors compare these data with those of Western studies and discuss the possible factors influencing psychiatric consultation in China.

High spatial resolution in vivo 2D (1)H magnetic resonance spectroscopic imaging of human muscles with a band-selective technique

This report demonstrates a 2D (1)H magnetic resonance spectroscopic imaging (MRSI) technique that can address some technical difficulties often encountered in MRS studies of human muscles. A preliminary application of this whole-slice technique in human skeletal muscles demonstrates clearly noticeable differences in (1)H metabolite spectra between different human muscles. This observation illustrates the importance of multi-voxel and high spatial resolution in a heterogeneous environment. This technique is robust, can be easily implemented on a commercial MR scanner, and should prove useful for investigators in both basic and clinical (1)H MRS studies.

Water modeled signal removal and data quantification in localized MR spectroscopy using a time-scale postacquistion method

We have previously shown the continuous wavelet transform (CWT), a signal-processing tool, which is based upon an iterative algorithm using a lorentzian signal model, to be useful as a postacquisition water suppression technique. To further exploit this tool we show its usefulness in accurately quantifying the signal metabolites after water removal. However, due to the static field inhomogeneities, eddy currents, and "radiation damping," the water signal and the metabolites may no longer have a lorentzian lineshape. Therefore, another signal model must be used. As the CWT is a flexible method, we have developed a new algorithm using a gaussian model and found that it fits the signal components, especially the water resonance, better than the lorentzian model in most cases. A new framework, which uses the two models, is proposed. The framework iteratively extracts each resonance, starting by the water peak, from the raw signal and adjusts its envelope to both the lorentzian and the gaussian models. The model giving the best fit is selected. As a consequence, the small signals originating from metabolites when selecting, removing, and quantifying the dominant water resonance from the raw time domain signal are preserved and an accurate estimation of their concentrations is obtained. This is demonstrated by analyzing (1H) magnetic resonance spectroscopy unsuppressed water data collected from a phantom with known concentrations at two different field strengths and data collected from normal volunteers using two different localization methods.

Cytochrome P-450scc-mediated oxidation of (20S)-22-thiacholesterol: characterization of mechanism-based inhibition

(20S)-22-thiacholesterol (1) is found to be a potent competitive inhibitor of pregnenolone biosynthesis from cholesterol by purified reconstituted bovine adrenal cytochrome P-450scc. The apparent dissociation constant Kd, determined from difference spectra, is 0.6 microM, close to the value from kinetic studies for the apparent inhibition constant, Ki, of 0.8 microM. Studies of the time course of pregnenolone production indicate that under turnover conditions the competitive inhibitor (1) is converted to a tighter binding inhibitor, shown to be (20S,22R)-22-thiacholesterol S-oxide (4), with high diastereoselectivity and in a time-dependent manner. Both the diastereomeric sulfoxides, (20S,22S)-22-thiacholesterol S-oxide (3) and (20S,22R)-22-thiacholesterol S-oxide (4), exhibit properties consistent with their being competitive versus cholesterol, but the (22R)-sulfoxide (4) binds approximately 10 times more tightly than the (22S) diastereomer (3). The apparent Kd values of sulfoxides 4 and 3 are 0.1 and 1.14 microM, respectively. EPR and absorption spectroscopic studies of enzyme-inhibitor complexes suggest direct coordination of the oxygen atom of the (22R)-sulfoxide (4) with the catalytic heme center. This implies that the inhibitor operates by directly blocking further reaction at the active site heme group, with a substantial lifetime of the enzyme-inhibitor complex.

Electrolytic partitioning of uranium and plutonium based on a new type of electrolytic mixer-settler

The design of a new type of electroreduction mixer-settler for the partitioning of uranium and plutonium during the Purex process, which is featured with E-shaped cathodes and U-shaped anodes in settling chamber, is described and the operational results achieved using this equipment are presented. The results show that this new type of mixer-settler has excellent separation performances. The flow rate of organic feed solution is 3 mL/min and the flow ratio of feed solution (1BF) to aqueous back extraction stream (1BX) and to organic wash stream (1BS) is 4/1/1. For an organic feed of 84 g/L uranium and 1.40 ⁓ 2.64 g/L plutonium, both the separation factor of plutonium from uranium and that of uranium from plutonium are apparently higher than 104

Pancreatic sarcomatoid carcinoma: CT, MRI, and 18F-FDG PET/CT features

AIM

To investigate computed tomography (CT), magnetic resonance imaging (MRI), and combined 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/CT features of pancreatic sarcomatoid carcinoma (PSC).

MATERIALS AND METHODS

The hospital database was searched retrospectively for the patients with PSC confirmed at histopathology after surgery. Ten patients who underwent unenhanced and enhanced CT (n=4), unenhanced and enhanced MRI (n=2), ¹⁸F-FDG PET/CT (n=2), and both enhanced CT and ¹⁸F-FDG PET/CT (n=2) were enrolled. Two patients underwent additional delayed PET/CT. The maximum standardised uptake value (SUVmax) was measured on PET/CT images.

RESULTS

Eleven lesions were detected in 10 patients. Solid and cystic components (n=6), intratumoural haemorrhage (n=1), nodular calcification (n=2), main pancreatic duct dilatation resulted from lesion obstruction (n=5) or compression (n=3), cholangiectasis (n=5), vascular and peripheral organ invasion (n=5 and 6, respectively), hepatic and lymphatic metastases (n=4 and 2, respectively) were detected. All five lesions in four patients who underwent PET/CT showed intense FDG uptake on PET/CT with SUVmax (16, range 10.9-21.1). Increase of FDG uptake (SUVmax = 18.9, 20.1, and 27.3, respectively) was revealed on the delayed scan of three lesions in two patients.

CONCLUSIONS

PSCs were more commonly ill-defined solid cystic masses, which caused pancreatic duct obstruction/compression without pancreatic parenchymal atrophy, and these masses on PET/CT showed high FDG uptake on both initial and delayed PET/CT.

[Chemical constituents of Phyllanthus urinaria L. and its antiviral activity against hepatitis B virus]

Studies on the chemical constituents of Phyllanthus urinaria and its antiviral activity against hepatitis B virus were completed. Eleven compounds have been isolated. Two of them are new compounds methyl ester dehydrochebulic acid and methyl brevifolin carboxylate. Antiviral experiments on HBsAg in vitro and liver damage caused by CCl4 have shown that. Phyllanthus urinaria possesses antiviral activities against HBV.

Analysis of risk factors for stone remnants and recurrence after lateral decubitus percutaneous nephrolithotomy

OBJECTIVE

This study aims to explore the risk factors for stone remnants and recurrence after lateral decubitus percutaneous nephrolithotomy (PCNL), providing insights to enhance the stone-free rate and reduce the stone recurrence rate.

PATIENTS AND METHODS

A retrospective analysis was conducted on 356 patients with renal or upper ureteral stones who underwent lateral decubitus PCNL from January 2015 to August 2022. Among them, 271 patients had complete clinical and follow-up data. General clinical information, perioperative data, and follow-up data were collected. Univariate and multivariate logistic regression analyses were performed to identify risk factors for stone remnants and recurrence after lateral decubitus PCNL.

RESULTS

The stone-free rate after lateral decubitus PCNL was 88.6% (195/271), and the stone recurrence rate within three years was 28.1% (76/271). Stone size (p<0.001) and stone co-infection (p=0.047) were identified as independent risk factors for stone remnants after lateral decubitus PCNL. Multiple stones (p=0.003) were an independent risk factor for stone recurrence after lateral decubitus PCNL.

CONCLUSIONS

Stone size and stone co-infection are independent risk factors for stone remnants after lateral decubitus PCNL. Multiple stones are an independent risk factor for stone recurrence after lateral decubitus PCNL.

[Study on bolus cyclosphamide treatment for 64 cases of lupus nephritis]

OBJECTIVE

To report on the dosing, efficacy and side-effects of bolus cyclosphamide treatment for lupus nephritis (LN).

METHODS

64 consecutive cases of LN with 10 or more erythrocytes per high-power field, proteinuria (> 1 g of protein per day) and serum creatinine increased (> 133 mumol/L) were treated by bolus therapy with cyclophosphamide (CTX) given monthly for 6 months and then quarterly for 18 months.

RESULTS

49 patients had renal remission (defined as < 10 erythrocytes per high-power field, absence of cellular casts, excretion of < 1 g of protein per day and normal serum creatinine). The mean of doses was 1.1 g for each time (0.6-1.6 g), the mean of times of bolus CTX needed was 3.6 (1-8 times). The adverse events were amenorrhea (in 41% female patients), herpes zoster (in 13% patients) and hemorrhagic cystitis (in 1 patient).

CONCLUSION

The results indicate that monthly bolus CTX therapy is effective and safe for patients with LN. Its adverse effect is relatively not a serious problem.

Analysis of risk factors for complications following transurethral resection of the prostate

OBJECTIVE

This study investigates the risk factors for complications following transurethral resection of the prostate and provides a reference for reducing postoperative complications.

PATIENTS AND METHODS

A retrospective analysis was conducted on 322 patients with benign prostatic hyperplasia who underwent transurethral resection of the prostate from April 2015 to January 2022. Among them, 214 patients had complete clinical and follow-up data. Clinical and follow-up data were collected, and both univariate and multivariate logistic regression analyses were performed to identify factors influencing the occurrence of postoperation transurethral resection of the prostate complications.

RESULTS

The incidence of complications after transurethral resection of the prostate was 19.16% (41/214). Among them, the incidence of Grade I-II complications was 14.96% (32/214), and Grade III-IV complications were 4.2% (9/214). The preoperative Quality of Life score (p<0.001) was identified as an independent risk factor for the occurrence of Grade I-II complications after transurethral resection of the prostate. The International Prostate Symptom Score (p=0.006) was identified as an independent risk factor for the occurrence of Grade III-IV complications after transurethral resection of the prostate.

CONCLUSIONS

The preoperative Quality of Life score is an independent risk factor for the occurrence of Grade I-II complications after transurethral resection of the prostate. The International Prostate Symptom Score is an independent risk factor for the occurrence of Grade III-IV complications after transurethral resection of the prostate.

[Chemical constituents of the leaves of Crataegus pinnatifida Bge. var. major N. E. Br]

Compounds were isolated from the aqueous extract of the leaves of Crataegus pinnatifida var. major and seven of them were identified as 2-(4-hydroxybenzyl)malic acid, quercetin, hyperin, vitexin, rhamnosylvitexin, diethylamine hydrochloride and sorbitol respectively by UV, IR, NMR, MS, some chemical techniques by comparison with the standard spectra of known compounds.

["Double Grooves-Double Rings" technique of transurethral Thulium laser enucleation of the prostate: learning curve of single surgeon]

Objective: To evaluate the learning curve of the "Double Grooves-Double Rings" (DGDR) technique of transurethral Thulium laser enucleation of the prostate (ThuLEP) for benign prostatic hyperplasia (BPH) by a single surgeon. From June 2021 to July 2022, 84 patients mean age (69.0±8.0) years,preoperative prostate volume (90.9±40.3)ml with BPH underwent ThuLEP in the Department of Urology, Peking University First Hospital.Performed by a single surgeon who had no experience of transurethral resection of prostate (TURP) and any laser surgeries. The case scatter plots with the best fitting line were drawn to analyze the learning curve. According to the date of the surgeries, the patients were equally divided into three learning stages (28 patients for each group). The T-PSA,prostate volume,operative time,enucleation time, enucleation efficiency,catheter indwelling time, hemoglobin drop and perioperative complications (including re-TURP, blood transfusion, stress incontinence≥3 months and urethral stricture) were compared among the groups. The learning curve was divided into three stages, and the cutting point was shown on the 14^th case. Except the prostate volume [stage1 (75.7±30.7) ml, stage2 (93.40±39.6)ml, stage3 (103.5±46.2) ml, P<0.05], there was no significant difference of the baseline data between three groups (P>0.05). Compared with those of stage 1(100.6±24.7) min,(0.55±0.22) g/min, a statistically significant improvement was observed in both of the operative time and the enucleation efficiency among stage 2[(84.5±36.6) min, (0.87±0.33) g/min and stage 3 (71.2±26.3) min, (1.27±0.45) g/min, P<0.05]. The learning curve of the DGDR technique for ThuLEP can be divided into three stages. A ThuLEP beginner can preliminarily master this technique after completing 14 cases.