[Geographic environment-related research advances on children's myopia: intraocular and environmental exposure factors and analytical methods]

Myopia has become a global phenomenon, transitioning into a significant public health issue of worldwide reach. The escalating prevalence of myopia may lead to an increase in the incidence of related complications, potentially resulting in irreversible vision damage for individuals. This not only causes considerable economic strain on societies but also poses a serious threat to vital sectors like national defense. This review outlines various external and internal exposure factors related to childhood myopia. It places particular focus on the analysis of the interaction between geographical environmental factors and internal exposure factors, and examines the limitations of applying traditional methods in studying the relationship between childhood myopia and geographical environmental factors. The paper also introduces two spatial regression methodologies based on frequency estimation and Bayesian estimation, summarizing their feasibility and merits when applied in the study of external exposure elements related to childhood myopia. Finally, it provides a fresh perspective on regional childhood myopia prevention strategies that are conscious of geographical environmental factors.

[Analysis on influencing factors on loneliness in the elderly aged 60 and above in China]

Objective: To analyze the influential factors of loneliness in the elderly aged ≥60 years in China. Methods: Data used in this study were obtained from participants aged ≥60 years from the China Longitudinal Aging Social Survey, with a sample size of 7 593. Loneliness was measured with loneliness scale, and the influence of subjective and objective factors on loneliness and their interaction were analyzed with stepwise linear regression model and simple slope test. SPSS 25.0 was used for statistical analysis. PROCESS 3.3 macro program was used for simple slope test. Results: A total of 8 926 participants were included. Among the objective factors, the elderly with poor family network have a higher level of loneliness (P<0.05), and community provision of elderly care services could reduce the loneliness of the elderly (P<0.05). Elderly people with subjective aging age ≤60 years old and poor social adaptation and emotional perception have higher levels of loneliness (all P<0.05). Subjective aging age plays a negative regulatory role in the impact of community elderly care services on loneliness (P<0.05), Social adaptation and emotional perception play a negative regulatory role in the impact of family network on loneliness (P<0.05). Conclusions: Elderly people aged ≥60 years of feeling of loneliness was affected by both subjective and objective factors and subjective factors play an important regulatory role in the influence of objective factors on elderly people's feeling of loneliness in China. Therefore, while creating a good aging environment to provide strong external support for the elderly, the subjective initiative of the elderly should also be fully mobilized, to alleviate the loneliness of the elderly from these two aspects.

[Research progress on the effectiveness of smallpox vaccination against mpox virus infection]

With the expansion of mpox virus infection from endemic to a global epidemic in 2022, the WHO declared that the mpox event constituted a Public Health Emergency of International Concern. Due to the high degree of gene sequence similarity among orthopox viruses and cross-reactive antibodies induced by orthoviruses, smallpox vaccination may affect the immune response induced by mpox virus infection. The analysis of the protective effects of smallpox vaccination against mpox virus infection will help define the focus of prevention and control. In this review, we clarify the protection of the smallpox vaccine against mpox virus infection by analyzing the correlation between smallpox vaccination, immune response status, and clinical data and providing evidence for the prevention, control, and strategies of mpox epidemics.

[Clinical research progress of human respiratory syncytial virus vaccine]

Human respiratory syncytial virus (HRSV) is one of the main pathogen causing severe acute lower respiratory tract infections in infants and the elderly, with high incidence rate and mortality worldwide. Vaccine is one of the important measure to prevent infection, transmission and severe disease of HRSV, but currently there is no officially approved preventive vaccine for prevention of HRSV in the world. This paper reviews and analyzes the current research and development progress of HRSV vaccine, summarizes the design routes of different types of HRSV preventive vaccines, and discusses the difficulties and challenges in vaccine research and development, in order to provide reference for the research and development of HRSV vaccine and the development of clinical trials.

Clinical characteristics of 14 pediatric mycoplasma pneumoniae pneumonia associated thrombosis: a retrospective study

OBJECTIVE

This study aimed to investigate the clinical characteristics and long-term prognosis of mycoplasma pneumoniae pneumonia (MPP)-associated thrombosis and to gain a better understanding of the diagnosis and treatment of the disease.

METHODS

The medical records of 14 children with MPP-associated thrombosis between January 2016 and April 2020 were retrospectively reviewed at the Tianjin Children's Hospital.

RESULTS

The ages of the patients ranged from 3 to 12 years old. Among the 14 cases, there were five cases of pulmonary embolism, two cases of cerebral infarction, one case of splenic infarction, one case of cardiac embolism, two cases of cardiac embolism with comorbid pulmonary embolism, one case of internal carotid artery and pulmonary embolism, one case of combined internal carotid artery and the cerebral infarction, and one case combined cardiac embolism and lower limb artery embolism. All cases had elevated D-dimer levels. After thrombolysis and anticoagulation therapy, three cases with cerebral embolism still suffered from neurological sequelae. In contrast, the remaining cases did not develop complications.

CONCLUSION

MPP-associated thrombosis can occur in any vessel of the body. Thrombosis-associated symptoms may be complex and non-specific. Elevated D-dimer levels in a child with refractory mycoplasma pneumoniae pneumonia should raise suspicion of thrombosis. The long-term prognosis of thrombosis was favorable after the timely administration of anticoagulant therapy.

Alteration of the faecal microbiota composition in patients with constipation: evidence of American Gut Project

There is limited information is known about the composition difference of the gut microbiota in patients with constipation and healthy controls. Here, the faecal 16S rRNA fastq sequence data of microbiota from the publicly available American Gut Project (AGP) were analysed. The tendency score matching (PSM) method was used to match in a 1:1 manner to control for confounding factors age, gender, body mass index (BMI), and country. A total of 524 participants including 262 patients with constipation and 262 healthy controls were included in this analysis. The richness and evenness of the gut microbiota in the constipation group were significantly lower than those in the control group. The dominant genera in the constipation group include Escherichia_Shigella, Pseudomonas, and Citrobacter. The dominant genera in the control group include Faecalibacterium, Prevotella, Roseburia, Clostridium_XlVa, and Blautia. The abundance of three butyrate production-related pathways were significantly higher in the constipation group than in the control groups. There was no significant difference in the diversity and gut microbiota composition in patients with constipation at different ages. In conclusion, patients with constipation showed gut microbiota and butyrate metabolism dysbiosis. This dysbiosis might provide a reference for the diagnosis and clinical therapy of diseases.

[Research progress of LI-RADS categories and imaging features in predicting the prognosis of liver tumors]

The liver imaging reporting and data system (LI-RADS) is an imaging assessment system that standardizes the diagnosis of hepatocellular carcinoma (HCC), indicating the benign and malignant tumor through categories as well as major and ancillary features. The higher the LI-RADS category ranking, the higher the corresponding HCC likelihood and malignancy risk. Therefore, early diagnosis and prediction of the prognostic risk factors of liver tumors by preoperative imaging have important clinical significance for improving the survival rate and prognosis of patients. This article reviews the research progress of LI-RADS categories and related imaging features in predicting the prognosis of liver tumors.

[Evaluation of vestibular-evoked myogenic potential for functional integrity of the brain stem in Kennedy's disease]

Objective: To investigate whether vestibular-evoked myogenic potentials(VEMPs) can be used to assess brainstem involvement in patients with Kennedy's disease (KD). Method: This was a case-control study.Twenty consecutive patients with genetically confirmed KD and 20 age-and sex-matched healthy subjects were enrolled from November 2018 to September 2020.All subjects were tested for three types of VEMPs, including cervical VEMP (c-VEMP) recorded by the sternocleidomastoid muscle (parameter:p13, n23), masseter VEMP (m-VEMP) recorded by the masseter muscle(parameter: p11), and ocular VEMP (o-VEMP) recorded by the inferior oblique muscle (parameter n10, p15).The latency of each wave, interside peak latency and interpeak latency of c-VEMP, the corrected amplitude and amplitude asymmetry ratio were recorded. Bilateral sternocleidomastoid muscle (SCMM) electromyography (EMG) was performed. The spinal cord and bulbous muscular atrophy functional rating scale (SBMAFRS) was used for assessment. Results: The mean p13 latency of c-VEMP was (15.5±1.4)ms, which was longer than that of the control group[(13.3±0.9)ms](P<0.05); the mean n23 latency was(25.5±1.4)ms, which was also longer than that of the control group[(22.5±1.0)ms] (P<0.05); the difference of bilateral p13[(2.3±0.6)ms] was significantly higher than that of the control group(P<0.05). The abnormal rates of c-, m-, o-VEMP in KD patients were 75%(15/20), 30%(6/20) and 20%(4/20), respectively. There was a significant positive correlation between c-VEMP latency and course of disease in KD patients(left: r=0.715, 0.695, right: r= 0.708, 0.715, both P<0.05). However, c-VEMP latency was negatively correlated with SBMAFRS score (left: r=-0.701, -0.694, right: r=-0.644, -0.685, both P<0.05). Abnormal rates of SCMM EMG in KD group were as follows: 15%(3/20)of patients showed spontaneous potential in resting state and 45% (9/20) of patients exhibited simple recruitment. Conclusions: The c-VEMP latency is a sensitive tool for detecting lower brainstem involvement in patients with KD, and the degree of damage increases with prolongation of disease course. The o-and m-VEMP abnormalities indicate that some KD patients develop upper brainstem damage.

[Analysis of bacterial pathogens and clinical characteristics of children with respiratory tract infections in Tianjin]

Objective: To analyze the pathogenic bacteria and epidemiological characteristics in children with respiratory tract infection in Tianjin area. Methods: Retrospective case analysis was performed on 2 392 hospitalized children in the wards of respiratory diseases, intensive care unit and special care ward of Tianjin Children's Hospital from June 2018 to May 2019. Thirteen pathogenic bacteria in deep sputum and bronchoalveolar lavage fluid samples were detected by loop-mediated isothermal amplification. The laboratory data and clinical characteristics of the infected children were analyzed, and the comparison between groups was performed by t test or χ² test. Results: Among 2 392 cases, 1 407 were males and 985 females. There was no significant difference in the detection rate between males and females (72.5% (1 020/1 407) vs.74.2% (731/985), χ²=0.87, P=0.35). A total of 1 751 strains and 12 kinds of positive respiratory pathogens were detected, with a detection rate of 73.2%. Among them, 913 (38.2%) strains were Mycoplasma pneumoniae (MP), 514 (21.5%) were Streptococcus pneumoniae (Sp), 381 (15.9%) were Methicillin-resistant Staphylococcus aureus (MRSA) and 279 (11.7%) were Hemophilus influenzae (Hi). There was significant difference in the detection rate of pathogens among different age groups (χ²=83.67, P<0.01). The positive rate of alveolar lavage fluid group was higher than that of deep sputum fluid group [81.6% (614/752) vs. 69.3% (1 137/1 640), χ²=39.89, P<0.01]. The length of hospital stay of children infected with different pathogens was significantly different (all P<0.01). There was significant difference in duration of fever among children infected with different pathogens (χ²=228.69,103.56, 3.96, 27.38,24.50,41.66, all P<0.05). There were 63 (7.7%) cases of atelectasis, 260 (31.9%) cases of pleurisy and 120 (14.7%) cases of pleural effusion in MP children. Children with Sma were most likely to involve the heart system (2/9), and children with Eco infection had a higher incidence of complications such as those of blood (3/19), urinary (2/19), digestive systems(4/19), systemic inflammatory response syndrome and sepsis (1/19). Conclusions: The main bacterial pathogens of respiratory tract infection in children in Tianjin were MP, Sp, MRSA and Hi. It is suggested that clinicians should not only pay attention to the respiratory symptoms of children, but also pay attention to the complications caused by bacterial pathogen infection, so as to prevent the deterioration of the disease and improve the prognosis.

Comparison of peripheral artery plaque characteristics between ACS patients with plaque rupture and plaque erosion in culprit coronary artery: an OCT and ultrasound study

Background

Recent research has found that the characteristics of peripheral arterial plaque are related to the increased risk of cardiovascular disease, however, the relationship of plaque characteristics between peripheral artery and coronary is still unknown.

Purpose

To assess the correlation between coronary plaque characteristics assessed by optical coherence tomography (OCT) and peripheral artery plaque characteristics assessed by ultrasound.

Methods

150 patients with acute coronary syndrome (ACS) underwent coronary angiography were prospectively enrolled. OCT imaging of culprit vessel were performed during the procedure and ultrasound examination of bilateral carotid, iliofemoral and popliteal arteries was performed during hospitalization after procedure. Panvascular disease was defined as the presence of observable plaques in two or more vascular beds. Patients were divided into plaque rupture (PR) group and plaque erosion (PE) group according to culprit plaque characteristics on OCT.

Results

There were 132 (88%) ACS patients had panvascular disease in which 36 (24%) with generalized atherosclerosis (4 sites) and the prevalence of panvascular atherosclerosis in PR group was significantly higher than in PE group especially in carotid arteries and iliofemoral arteries (Figure 1, Figure 2). Compared to PE group, PR group had higher carotid plaque score (p=0.001) which indicates more plaques and severer atherosclerosis. Moreover, there were larger intima-media thickness (IMT) of iliofemoral arteries (6.9±1.4mm vs. 6.5±1.1mm, p=0.036) and more calcified plaques in PR group.

Conclusions

Panvascular disease is highly prevalent in ACS patients especially in patients with plaque rupture in culprit vessel, in which more than half of the patients had plaques in more than 3 sites of vascular beds. In addition, patients with plaque rupture had thicker iliofemoral IMT and higher panvascular atherosclerosis burden, which indicates that characteristics of coronary plaques are the focal expression of plaques in the whole panvcascular system.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Key R&D Program of China Figure 1. Prevalence of panvascular disease in ACSFigure 2. Comparison of peripheral artery plaques

[Evaluation of demand of resources for laboratory testing and prevention and control of COVID-19 in the context of global pandemic]

Objective: To rapidly evaluate the level of healthcare resource demand for laboratory testing and prevention and control of corona virus disease 2019 (COVID-19) in different epidemic situation, and prepare for the capacity planning, stockpile distribution, and funding raising for infectious disease epidemic response. Methods: An susceptible, exposed, infectious, removed infectious disease dynamics model with confirmed asymptomatic infection cases and symptomatic hospitalized patients was introduced to simulate different COVID-19 epidemic situation and predict the numbers of hospitalized or isolated patients, and based on the current COVID-19 prevention and control measures in China, the demands of resources for laboratory testing and prevention and control of COVID-19 were evaluated. Results: When community or local transmission or outbreaks occur and total population nucleic acid testing is implemented, the need for human resources is 3.3-89.1 times higher than the reserved, and the current resources of medical personal protective equipment and instruments can meet the need. The surge in asymptomatic infections can also increase the human resource demand for laboratory testing and pose challenge to the prevention and control of the disease. When vaccine protection coverage reach ≥50%, appropriate adjustment of the prevention and control measures can reduce the need for laboratory and human resources. Conclusions: There is a great need in our country to reserve the human resources for laboratory testing and disease prevention and control for the response of the possible epidemic of COVID-19. Challenges to human resources resulted from total population nucleic acid testing and its necessity need to be considered. Conducting non-pharmaceutical interventions and encouraging more people to be vaccinated can mitigate the shock on healthcare resource demand in COVID-19 prevention and control.

[Association between rare UBQLN2 variants and amyotrophic lateral sclerosis in Chinese population]

Objective: To explore the association between rare UBQLN2 variants and amyotrophic lateral sclerosis (ALS) in Chinese population, and the characteristic of phenotypes of their carriers. Methods: A total of 166 ALS patients who visited Department of Neurology of Peking University Third Hospital between January 2018 and July 2020 were recruited. The next-generation sequencing was performed to screen possible pathogenic rare variants of UBQLN2. Meanwhile, control individuals were obtained from 1000 Genome Project (2 504 samples) and an in-house whole-exome sequencing database (1 812 samples), separately. The sequence kernel association test (SKAT) and the SKAT-optimal test (SKAT-O) were used to identify the association between UBQLN2 rare variants and ALS. The clinical characteristics of rare variant carriers were analyzed. Results: A total of 33 familiar ALS and 133 sporadic ALS of Chinese ancestry were enrolled. Of the 166 ALS patients, 12.7% had bulbar-onset, 85.5% had limb-onset, and 5 cases were ALS with frontotemporal dementia (3.0%). The male-to-female ratio was 1.68∶1, with a mean age at symptom onset of (43.8±12.2) years. Three possible pathogenic rare variants of UBQLN2 were detected, including c.128A>G (p.Lys43Arg), c.142G>T (p.Val48Leu) and c.1451T>G (p.Val484Gly), and all of them were novel missense mutations. Compared with 1000 Genome Project, SKAT and SKAT-O showed a P value of 2.49×10^-6 and 9.22×10^-7, respectively. While compared with the in-house database, SKAT and SKAT-O revealed a P value of 1.42×10^-3 and 1.10×10^-3, respectively. Patients who carried rare UBQLN2 variants were with a higher rate of bulbar-onset (2/3 vs 19/163, P=0.042). Conclusion: Rare variants of UBQLN2 are associated with ALS in Chinese population, and mutation of UBQLN2 may be relevant to bulbar-onset.

Switchable 3D optofluidic Y-branch waveguides tuned by Dean flows

Optical branch waveguides are one of the most important optical elements and have been widely exploited for optical communication systems. However, prevailing devices are typically solid and have limit in tunability. Liquid optical devices have attracted more interest for the advantage of tunability of liquid media, but their signals suffer serious leakage if the refractive index (RI) of liquid is smaller than that of solid channels. This paper demonstrates the tunable three-dimensional (3D) optofluidic Y-branch waveguides in plannar microchannels by simply introducing Dean flow. This device can reconfigure 3D Y-branch profiles and separate the intensity of light as tunable ratio from 0 to 1 by adjusting the flow rates with low loss. Different from the prevailing 2D liquid counterparts, the 3D configuration offer much more freedom in the selection of liquid media as liquid's RI can be totally independent to the solid channel structure. The transmission loss through the device is estimated to 0.97 db when the splitting angle is 10°, which shows the light is confined better in the 3D liquid structures than traditional 2D liquid counterparts. The Y-branch waveguides show potential in applications of integrated optofluidic devices.

Intraosseous Injection of Simvastatin in Poloxamer 407 Hydrogel Improves Pedicle-Screw Fixation in Ovariectomized Minipigs

BACKGROUND

Osteoporosis leads to poor osseointegration and reduces implant stability. Statins have been found to stimulate bone formation, but the bioavailability from oral administration is low. Local application may be more effective at augmenting bone formation and enhancing implant stability. This study was performed to evaluate the efficacy of an intraosseous injection of simvastatin in thermosensitive poloxamer 407 hydrogel to enhance pedicle-screw fixation in calcium-restricted ovariectomized minipigs.

METHODS

Nine mature female Guangxi Bama minipigs underwent bilateral ovariectomy and were fed a calcium-restricted diet for 18 months. Simvastatin (0, 0.5, or 1 mg) in thermosensitive poloxamer 407 hydrogel was injected into the lumbar vertebrae (L4-L6), and titanium alloy pedicle screws were implanted. Bone mineral density (BMD) measurements of the lumbar vertebrae were determined by dual x-ray absorptiometry (DXA) before and 3 months after treatment. The lumbar vertebrae were harvested and analyzed with use of microcomputed tomography, biomechanical pull-out testing, histological analysis, and Western blot analysis for bone morphogenetic protein (BMP)-2 and vascular endothelial growth factor (VEGF) expression.

RESULTS

Evaluation over a 3-month study period demonstrated that the BMD of the vertebrae injected with 0.5 and 1.0 mg of simvastatin had increased by 31.25% and 31.09%, respectively, compared with vehicle-only injection (p ≤ 0.00014 for both) and increased by 32.12% and 28.16%, respectively, compared with the pre-treatment levels (p < 0.0001 for both). A single injection of simvastatin in poloxamer 407 increased trabecular volume fraction, thickness, and number and decreased trabecular separation (p ≤ 0.002). The bone formation and mineral apposition rates significantly increased (p ≤ 0.023). The percentage of osseointegration in the simvastatin 0.5 and 1-mg groups was 46.54% and 42.63% greater, respectively, than that in the vehicle-only group (p ≤ 0.006), and the maximum pull-out strength was 45.75% and 51.53% greater, respectively, than in the vehicle-only group (p ≤ 0.0005). BMP-2 and VEGF expressions were higher than for the vehicle-only injection.

CONCLUSIONS

A single intraosseous injection of simvastatin in thermosensitive poloxamer 407 hydrogel stimulated bone formation, increased BMD, improved bone microstructure, promoted osseointegration, and significantly enhanced the stability of pedicle screws in calcium-restricted ovariectomized minipigs.

CLINICAL RELEVANCE

These results provide rationale for evaluating intraosseous injection of simvastatin in poloxamer 407 to enhance implant fixation in patients with osteoporosis.

Comparison of mercury sulfides with mercury chloride and methylmercury on hepatic P450, phase-2 and transporter gene expression in mice

Zuotai (mainly β-HgS) and Zhusha (also called as cinnabar, mainly α-HgS) are used in traditional medicines in combination with herbs or even drugs in the treatment of various disorders, while mercury chloride (HgCl2) and methylmercury (MeHg) do not have known medical values but are highly toxic. This study aimed to compare the effects of mercury sulfides with HgCl2 and MeHg on hepatic drug processing gene expression. Mice were orally administrated with Zuotai (β-HgS, 30mg/kg), α-HgS (HgS, 30mg/kg), HgCl2 (33.6mg/kg), or MeHg (3.1mg/kg) for 7days, and the expression of genes related to phase-1 drug metabolism (P450), phase-2 conjugation, and phase-3 (transporters) genes were examined. The mercurials at the dose and duration used in the study did not have significant effects on the expression of cytochrome P450 1-4 family genes and the corresponding nuclear receptors, except for a slight increase in PPARα and Cyp4a10 by HgCl2. The expressions of UDP-glucuronosyltransferase and sulfotransferase were increased by HgCl2 and MeHg, but not by Zuotai and HgS. HgCl2 decreased the expression of organic anion transporter (Oatp1a1), but increased Oatp1a4. Both HgCl2 and MeHg increased the expression of multidrug resistance-associated protein genes (Mrp1, Mrp2, Mrp3, and Mrp4). Zuotai and HgS had little effects on these transporter genes. In conclusion, Zuotai and HgS are different from HgCl2 and MeHg in hepatic drug processing gene expression; suggesting that chemical forms of mercury not only affect their disposition and toxicity, but also affect their effects on the expression of hepatic drug processing genes.

[Assessment of upper motor neuron dysfunction by triple stimulation technique in patients with Charcot-Marie-Tooth disease]

OBJECTIVE

To investigate the presence of upper motor neuron dysfunction in patients with Charcot-Marie-Tooth disease (CMT) by triple stimulation technique (TST) to provide evidence for gene diagnosis.

METHODS

A total of 65 CMT patients confirmed by genetic testing from Peking University Third Hospital between August 2013 and August 2015, underwent physical examination and routine electrophysiological tests and triple stimulation technique. The TST combined transcranial magnetic stimulation (TMS) of the motor cortex with peripheral collision studies. The results were expressed by the TST amplitude ratio (TST test/ TST control). Based on the result of physical examination and the ratio of TST, the function of upper motor neuron was assessed.

RESULTS

All of the CMT patients had typical presentations and were confirmed genetically. Hyperreflexia, Babinski sign and muscular hypertonia were discovered in lower limbs in 7 CMT patients, while 2 patients complicated with hyperreflexia and Hoffmann sign in upper limbs. TST amplitude ratio was significantly altered in 10 patients, including 5 patients with pyramid sign: hyperreflexia, Babinski sign and muscular hypertonia was discovered in lower limbs while 2 patients complicated with hyperreflexia and Hoffmann sign in upper limbs. The disease-causing mutations were: MFN2 mutations in 5 patients, 1 patient with BSCL2 mutation, 3 patients with GJB1 mutations and 1 patient with GDAP mutation. In summary, 18.5% (12 patients) of the 65 CMT patients had upper motor neuron dysfunction based on the result of physical examination and the ratio of TST.

CONCLUSION

Upper motor neuron dysfunction may be found in CMT patients, which may provide clues for the testing of disease-causing mutations.

A single CT-guided percutaneous intraosseous injection of thermosensitive simvastatin/poloxamer 407 hydrogel enhances vertebral bone formation in ovariectomized minipigs

The ultimate goal of osteoporosis treatment is prevention of fragile fracture. Local treatment targeting specific bone may decrease the incidence of osteoporotic fractures. We developed an injectable, thermosensitive simvastatin/poloxamer 407 hydrogel; a single CT-guided percutaneous intraosseous injection augmented vertebrae in ovariectomized minipigs.

INTRODUCTION

The greatest hazard associated with osteoporosis is local fragility fractures. An adjunct, local treatment might be helpful to decrease the incidence of osteoporotic fracture. Studies have found that simvastatin stimulates bone formation, but the skeletal bioavailability of orally administered is low. Directly delivering simvastatin to the specific bone that is prone to fractures may reinforce the target bone and reduce the incidence of fragility fractures.

METHODS

We developed an injectable, thermosensitive simvastatin/poloxamer 407 hydrogel, conducted scanning electron microscopy, rheological, and drug release analyses to evaluate the delivery system; injected it into the lumbar vertebrae of ovariectomized minipigs via minimally invasive CT-guided percutaneous vertebral injection. Three months later, BMD, microstructures, mineral apposition rates, and strength were determined by DXA, micro-CT, histology, and biomechanical test; expression of VEGF, BMP2, and osteocalcin were analyzed by immunohistochemistry and Western blots.

RESULTS

Poloxamer 407 is an effective controlled delivery system for intraosseous-injected simvastatin. A single injection of the simvastatin/poloxamer 407 hydrogel significantly increased BMD, bone microstructure, and strength; the bone volume fraction and trabecular thickness increased nearly 150 %, bone strength almost doubled compared with controls (all P < 0.01); and induced higher expression of VEGF, BMP2, and osteocalcin.

CONCLUSIONS

CT-guided percutaneous vertebral injection of a single simvastatin/poloxamer 407 thermosensitive hydrogel promotes bone formation in ovariectomized minipigs. The underlying mechanism appears to involve the higher expression of VEGF and BMP-2.

Mineral association changes the secondary structure and dynamics of murine amelogenin

Amelogenin is one of the key protein constituents responsible for the exquisite organization of the calcium phosphate crystals in enamel. Amelogenin forms into nanospheres in solution, while its association with hydroxyapatite is also essential to enamel development. Structural information of full-length amelogenin in either of these physiologically important forms has the potential to provide mechanistic information; however, these data are limited because of the difficulty of determining the structure of large protein complexes and proteins bound to surfaces. To obtain structural insights into amelogenin during these early stages of enamel development, we used a lysine-specific (13)C-, (15)N-labeled sample of murine amelogenin to provide insight into the structure of the hydroxyapatite (HAP)-binding domains of the protein. A combination of one-and two-dimensional solid-state NMR experiments was used to obtain molecular-level insights into the secondary structure and dynamics of full-length amelogenin within a nanosphere-gel and on the surface of HAP. Regions of amelogenin that appear to be primarily random coil in the nanosphere-gel adopt a β-strand structure and are less mobile with HAP binding, indicative of a structural switch upon binding that may be important in the role of amelogenin in enamel development.

Acoustic response of a rigid-frame porous medium plate with a periodic set of inclusions

The acoustic response of a rigid-frame porous plate with a periodic set of inclusions is investigated by a multipole method. The acoustic properties, in particular, the absorption, of such a structure are then derived and studied. Numerical results together with a modal analysis show that the addition of a periodic set of high-contrast inclusions leads to the excitation of the modes of the plate and to a large increase in the acoustic absorption.

Mutations in the ATP2C1 gene in Chinese patients with Hailey-Hailey disease

Hailey-Hailey disease (HHD; MIM 16960) is a rare autosomal dominant hereditary disorder characterized by recurrent eruption of vesicles and bullae, predominantly involving the body folds. It is caused by heterozygous mutations in the ATP2C1 gene, encoding the human secretory pathway Ca2+/Mn2+-ATPase protein 1 (hSPCA1). When we studied Chinese patients with HHD, we found two different heterozygous mutations, Q506X and G353V, the former previously reported in a Hungarian patient, and the latter being a novel mutation. In a 38-year-old patient from a four-generation pedigree with a 3-year history of severe recurrent blisters, we identified a C-->T transition at nucleotide 1696, c(1696C-->T), in exon 17 of ATP2C1, resulting in a nonsenes mutation, Gln506X, which resulted in a premature termination codon. In the second patient, who represented a occurrence of sporadic Hailey-Hailey disease, a G-->T transversion of nucleotide, c(G1238T), in exon 13 of ATP2C1 was detected, which resulted in a Gly353-->Val amino acid substitution (G353V). Our molecular findings further demonstrate that the mutational events in the human ATP2C1 gene encoding the hSPCA1 pump play an important role in the pathogenesis of HHD.

Transketolase gene expression in the cornea is influenced by environmental factors and developmentally controlled events

PURPOSE

Transketolase (TKT) has been proposed to be a corneal crystallin, and its gene and protein are abundantly expressed in the corneal epithelium of several mammals. A marked up-regulation of TKT gene expression coincides with the time of eyelid opening in the mouse. Here, we examined whether exposure to incident light contributes to the up-regulation of TKT gene expression during cornea maturation.

METHODS

Mice were raised in either standard light/dark cycling conditions or total darkness. In some cases, subcutaneous injections of epidermal growth factor (EGF) were given beginning on the day of birth to induce early eyelid opening. RNA was prepared from the corneas of mothers and pups and subjected to Northern blot analyses. In addition, the relative levels of TKT mRNA and/or enzyme activity were examined in the corneas of human, bovine, rat, chicken, and zebrafish.

RESULTS

TKT mRNA levels were 2.1-fold higher in the corneas of 25-day-old mouse pups ( 12 days after eyelid opening) that had been born and raised in light/dark conditions compared to pups born and raised in total darkness. By contrast, the level of TKT mRNA in the mature corneas of adult mice maintained in the dark for 2-8 weeks did not vary greatly from those of mice maintained in light/dark conditions. Interestingly, TKT mRNA levels in the corneas of dark-raised mice, although reduced, did exhibit the increase characteristically observed before and after eyelid opening. In addition, TKT mRNA levels were elevated fivefold in the corneas of 28-day-old mice raised in darkness and injected with EGF compared to uninjected mice also deprived of light. The EGF-injected mice opened their eyes 3 days early, and their corneal epithelium did not grossly differ from that of control mice. TKT mRNA and/or enzyme activity was found to be much higher in the corneas than in other tissues of humans, bovines, and rats but was extremely low in the corneas of chicken and zebrafish.

CONCLUSION

Our studies suggest that both exposure to incident light and events surrounding the process of eyelid opening play a role in the up-regulation of TKT gene expression observed during corneal maturation in mice. Light appears to play a less important role in the mature cornea in maintaining high levels of TKT gene expression. The low levels of TKT in the cornea of chicken and zebrafish support the notion that TKT acts as a taxon-specific enzyme-crystallin in mammals. The involvement of environmental signals for this putative, mammalian cornea crystallin contrasts with the purely developmental signals involved in the up-regulation of the crystallin genes of the lens.

Evidence for gelsolin as a corneal crystallin in zebrafish

We have shown that gelsolin is one of the most prevalent water-soluble proteins in the transparent cornea of zebrafish. There are also significant amounts of actin. In contrast to actin, gelsolin is barely detectable in other eye tissues (iris, lens, and remaining eye) of the zebrafish. Gelsolin cDNA hybridized intensely in Northern blots to RNA from the cornea but not from the lens, brain, or headless body. The deduced zebrafish gelsolin is approximately 60% identical to mammalian cytosolic gelsolin and has the characteristic six segmental repeats as well as the binding sites for actin, calcium, and phosphatidylinositides. In situ hybridization tests showed that gelsolin mRNA is concentrated in the zebrafish corneal epithelium. The zebrafish corneal epithelium stains very weakly with rhodamine-phalloidin, indicating little F-actin in the cytoplasm. In contrast, the mouse corneal epithelium contains relatively little gelsolin and stains intensely with rhodamine-phalloidin, as does the zebrafish extraocular muscle. We propose, by analogy with the diverse crystallins of the eye lens and with the putative enzyme-crystallins (aldehyde dehydrogenase class 3 and other enzymes) of the mammalian cornea, that gelsolin and actin-gelsolin complexes act as water-soluble crystallins in the zebrafish cornea and contribute to its optical properties.

Complete replication of human sperm genome in egg extracts from Xenopus laevis

To examine the ability of Xenopus egg extracts to support a complete replication cycle of human sperm genome, demembranated human spermatozoa were incubated with the extract from activated Xenopus laevis eggs. Most sperm heads were decondensed within 15 min. The heads became round within 30 min with diameters of 10-30 microns. The process of DNA replication in the pronuclei was monitored by two methods, bromodeoxyuridine incorporation and flow cytometry. The results indicate that DNA replication was initiated approximately 1.5 h after membrane structure formation and that it lasted up to 9 h. The amounts of DNA in most pronuclei were doubled by 4-9 h, depending on which donor toad was the source of the egg extract. Inclusion of the protein synthesis inhibitor, cycloheximide (100 micrograms/ml), had no obvious effect on human sperm DNA replication but appeared to prevent the pronuclei from degradation after a prolonged period (> 6 h) of incubation. After storage in liquid nitrogen for > 1.5 mo, the efficiency of the egg extracts in supporting sperm head decondensation and DNA replication was reduced for human sperm but not for Xenopus sperm. Possible applications of the use of Xenopus egg extract for human sperm activation and DNA replication are discussed.

Reperfusion arrhythmias in acute myocardial infarction

In 27 patients with acute myocardial infarction (MI) and their infarct-related coronary artery being completely occluded who received thrombolytic therapy or percutaneous transluminal coronary angioplasty, reperfusion was confirmed by immediate coronary angiography in 24. Reperfusion arrhythmias (RA) occurred in 19 (79.2%) of the patients, including ventricular arrhythmias in 13 (54.2%). Ventricular fibrillation and sustained ventricular tachycardia developed in 2 (8.4%) and accelerated idioventricular rhythm in 5 (20.8%), the latter was a reliable indicator of coronary recanalization. Transient sinus bradycardia or AV block occurred in 10 (66.7%) of the 15 patients with inferoposterior MI. The occurrence of RA was not related to the duration of ischemia; ventricular RA was also not related to the location of MI and the occurrence and severity of ischemic arrhythmias before reperfusion.

RFLP analysis of asymmetric somatic hybrids between Solanum tuberosum and irradiated S. brevidens

The nuclear genome composition of five asymmetric somatic hybrids, obtained by fusion of leaf protoplasts from Solanum tuberosum and gamma-irradiated leaf protoplasts from S. brevidens, have been analyzed at the molecular level. An analysis of 21 loci using linkage group-specific restriction fragment length polymorphism (RFLP) was included in the study. All five hybrids contained a complete set of the loci studied from S. tuberosum. The degree of elimination of alleles from the irradiated S. brevidens donor genome ranged from 10-65% in the five asymmetric hybrids analyzed. The detection of incomplete chromosomes, as well as non-parental bands in Southern hybridizations with RFLP markers, revealed extensive chromosome rearrangements in the asymmetric hybrids.

Analysis of the mitochondrial DNA of the somatic hybrids of Solanum brevidens and S. tuberosum using non-radioactive digoxigenin-labelled DNA probes

Mitochondrial (mt) DNAs of somatic hybrids obtained by electrical and chemical fusion of mesophyll protoplasts of S. brevidens and a dihaploid line of S. tuberosum PDH 40 were analysed by Southern hybridization using the digoxigenin-labelled mtDNA sequences nad5 or orf25. In the Southern analysis of the hybrid mtDNA probed with nad5, most of the 19 hybrids analyzed had an RFLP pattern similar, but not identical, to one of the parents, S. tuberosum, PDH40. Nineteen percent of the hybrids had most of the S. brevidens fragments. Five of the hybrids had an identical RFLP pattern to either one of the parents while another two hybrids had novel RFLP patterns. Similar results were obtained by Southern analysis with orf25. These results clearly show that mtDNA rearrangements had occurred at a high frequency in the somatic hybrids. There were no differences in the frequencies of rearrangements observed between the hybrids regenerated from chemical and electrical fusions.

Production of asymmetric hybrids between Solanum tuberosum and irradiated S. brevidens

Asymmetric somatic hybrids were obtained by fusion of Solanum tuberosum (PDH40) protoplasts with 300- or 500-Gy irradiated protoplasts of S. brevidens. These radiation doses were sufficient to prevent the growth of the S. brevidens protoplasts. Putative hybrids were selected on the basis of phenotype from regenerated shoots and identified with a S. brevidens-specific probe. From these, 31 asymmetric hybrids were confirmed by morphological characteristics, isoenzyme patterns and RFLP analysis. The morphology of the asymmetric hybrids was intermediate between that of S. tuberosum and symmetric hybrids of both species (obtained without irradiation treatment). Chromosome counts from 17 asymmetric hybrids showed that the chromosome number of the hybrids ranged from 31 to 64. The asymmetric hybrids probably had one or two genome complements (i.e. either 24 or 48 chromosomes) from S. tuberosum and 7-22 chromosomes from S. brevidens. There was no clear correlation between the radiation dose and the degree of elimination of the S. brevidens genome.

[Quantitative assessment of the effect of nitroglycerin on left ventricular function with two-dimensional echocardiography in patients with myocardial infarction]

The effect of sublingual and intravenous nitroglycerin (SLNTG and IVNTG) on left ventricular global and segmental systolic function was quantitatively assessed with two-dimensional echocardiography (2DE) in 28 cases of myocardial infarction (MI), including a group without heart failure of 13 and another group with heart failure of 15. The results showed that after SLNTG and IVNTG the left ventricular end-diastolic and end-systolic volumes were significantly decreased in both groups (P < 0.05-0.001), the left ventricular global systolic function was improved particularly in MI patients with heart failure during IVNTG. The wall motion in the normal and/or hypokinetic segments was enhanced after both SLNTG and IVNTG. It was shown that nitroglycerin could strengthen the left ventricular global systolic function in patients with MI.

Use of RAPD markers to screen somatic hybrids between Solanum tuberosum and S. brevidens

The identification of somatic hybrids between Solanum tuberosum and S. brevidens can be carried out using polymerase chain reaction (PCR) and arbitrary 10-mer primers to generate random amplified polymorphic DNA (RAPD) markers. Five commercial primers have been tested. Each primer directed the amplification of a genome-specific "fingerprint" for the fusion parents and S. brevidens. The size of the amplified DNA fragments ranged from 100 to 1800 base pairs. The somatic hybrids showed a combination of the parental banding profiles with four of the five primers surveyed, whereas regenerants from one of the parents had the same or a similar banding pattern to that of the parent. Thus RAPD markers provide a quick, simple and preliminary screening method for putative somatic hybrids.

Filtering noise from images with wavelet transforms

A new method of filtering MR images is presented that uses wavelet transforms instead of Fourier transforms. The new filtering method does not reduce the sharpness of edges. However, the new method does eliminate any small structures that are similar in size to the noise eliminated. There are many possible extensions of the filter.

Bacteriological composition and structure of granular sludge adapted to different substrates

The bacteriological composition and ultrastructure of mesophilic granular methanogenic sludge from a large-scale Upflow Anaerobic Sludge Blanket reactor treating wastewater from a sugar plant and of sludge granules adapted to ethanol and propionate were studied by counting different bacterial groups and by immunocytochemical methods. Propionate-grown granular sludge consisted of two types of clusters, those of a rod-shaped bacterium immunologically related to Methanothrix soehngenii and those consisting of two different types of bacteria with a specific spatial orientation. One of these bacteria reacted with antiserum against Methanobrevibacter arboriphilus AZ, whereas the other is most likely a propionate-oxidizing bacterium immunologically unrelated to Syntrophobacter wolinii. Sludge granules obtained from the large-scale Upflow Anaerobic Sludge Blanket reactor and granules cultivated on ethanol did not show the typical spatial orientation of bacteria. Examination of the bacterial composition of the three types of granules by light and electron microscopy, the most-probable-number method, and by isolations showed that M. arboriphilus and M. soehngenii were the most abundant hydrogenotrophic and acetoclastic methanogens in propionate-grown sludge. Methanospirillum hungatei and Methanosarcina barkeri predominated in ethanol-grown granules, whereas many morphotypes of methanogens were abundant in granules from the full-scale reactor.

Plant regeneration from protoplasts of Solanum species with potential agricultural value (S. hjertingii, S. polyadenium, S. capsicibaccatum)

Protoplasts have been isolated from three tuber-bearing Solanum species, S. hjertingii, S. polyadenium and S. capsicibaccatum, that are sexually incompatible with S. tuberosum, but possess potentially useful characters. For isolating protoplasts from leaves of in vitro shoot cultures of S. hjertingii and S. capsicibaccatum growth was improved by including silver thiosulfate in the medium. However, for S. polyadenium, leaves of pot-grown plants were the best source for protoplasts. Following protoplast division and culture, plants were regenerated from protoplasts of each of the species. The pattern of chromosome variation in regenerants was similar to that observed for other diploid and tetraploid Solanum species. The results indicate that it should be possible to introduce the potentially useful germplasm from these wild species into somatic hybrids with S. tuberosum by protoplast fusion.