Epidemiological characteristics of COVID-19 epidemic in Ejina banner, Inner Mongolia Autonomous Region, October 2021 / 中华流行病学杂志

Objective: To understand the epidemiological characteristics of COVID-19 epidemic in Ejina banner, Inner Mongolia, in October 2021 and provide evidence for the improvement of COVID-19 prevention and control. Methods: The information about the time, area and population distributions of COVID-19 cases in Ejina before November 13, 2021 and the gene sequencing result of the isolates were collected for a statistical descriptive analysis. Results: The first COVID-19 case in Ejina occurred on 7 October, 2021. A total of 164 COVID-19 cases were reported from October 19 to November 12. Most cases were distributed in 6 communities in Darahub (156 cases, 95.12%). The result of full gene sequencing of the isolates indicted that the pathogen was Delta variant (B.1.617.2). The male to female ratio of the cases was 1.3∶1. The age of cases ranged from 1 to 85 years, and the cases aged 20-59 years accounted for 78.66%. The main clinical symptoms were sore throat (91 cases, 91.92%), cough (49 cases, 49.49%) and fever (23 cases, 23.23%). Most cases were ordinary ones (81 cases, 49.39%) and mild ones (68 cases, 41.46%). The cases were mainly detected at the isolation points (84 cases, 51.22%) and through population based nucleic acid testing (62 cases, 37.80%). The basic reproduction number (R0) of COVID-19 was 5.3, the average incubation period was 3.9 days. The local government rapidly started Ⅳ level emergency response and conducted 10 rounds of nucleic acid tests. The transferring of travelers reduced the risk for the further spread of COVID-19 in Ejina. Conclusions: The epidemic of COVID-19 in Ejina characterized by strong transmission, short incubation period, herd susceptibility and case clustering. Delta variant (B.1.617.2) was the pathogen, which might be imported from Zeke port. Comprehensive prevention and control measures, such as closed-loop management and vaccination, should be continued. The successful transferring of the patients and travelers provided evidence for the effective and precise prevention and control of COVID-19 in a routine manner.

Platelet-Derived Growth Factor Receptor-α Subunit Targeting Suppresses Metastasis in Advanced Thyroid Cancer In Vitro and In Vivo

Thyroid cancer is the most common endocrine malignancy. Patients with well-differentiated thyroid cancers, such as papillary and follicular cancers, have a favorable prognosis. However, poorly differentiated thyroid cancers, such as medullary, squamous and anaplastic advanced thyroid cancers, are very aggressive and insensitive to radioiodine treatment. Thus, novel therapies that attenuate metastasis are urgently needed. We found that both PDGFC and PDGFRA are predominantly expressed in thyroid cancers and that the survival rate is significantly lower in patients with high PDGFRA expression. This finding indicates the important role of PDGF/PDGFR signaling in thyroid cancer development. Next, we established a SW579 squamous thyroid cancer cell line with 95.6% PDGFRA gene insertion and deletions (indels) through CRISPR/Cas9. Protein and invasion analysis showed a dramatic loss in EMT marker expression and metastatic ability. Furthermore, xenograft tumors derived from PDGFRA geneedited SW579 cells exhibited a minor decrease in tumor growth. However, distant lung metastasis was completely abolished upon PDGFRA gene editing, implying that PDGFRA could be an effective target to inhibit distant metastasis in advanced thyroid cancers. To translate this finding to the clinic, we used the most relevant multikinase inhibitor, imatinib, to inhibit PDGFRA signaling. The results showed that imatinib significantly suppressed cell growth, induced cell cycle arrest and cell death in SW579 cells. Our developed noninvasive apoptosis detection sensor (NIADS) indicated that imatinib induced cell apoptosis through caspase-3 activation. In conclusion, we believe that developing a specific and selective targeted therapy for PDGFRA would effectively suppress PDGFRA-mediated cancer aggressiveness in advanced thyroid cancers.

Platelet-Derived Growth Factor Receptor-α Subunit Targeting Suppresses Metastasis in Advanced Thyroid Cancer In Vitro and In Vivo

Thyroid cancer is the most common endocrine malignancy. Patients with well-differentiated thyroid cancers, such as papillary and follicular cancers, have a favorable prognosis. However, poorly differentiated thyroid cancers, such as medullary, squamous and anaplastic advanced thyroid cancers, are very aggressive and insensitive to radioiodine treatment. Thus, novel therapies that attenuate metastasis are urgently needed. We found that both PDGFC and PDGFRA are predominantly expressed in thyroid cancers and that the survival rate is significantly lower in patients with high PDGFRA expression. This finding indicates the important role of PDGF/PDGFR signaling in thyroid cancer development. Next, we established a SW579 squamous thyroid cancer cell line with 95.6% PDGFRA gene insertion and deletions (indels) through CRISPR/Cas9. Protein and invasion analysis showed a dramatic loss in EMT marker expression and metastatic ability. Furthermore, xenograft tumors derived from PDGFRA geneedited SW579 cells exhibited a minor decrease in tumor growth. However, distant lung metastasis was completely abolished upon PDGFRA gene editing, implying that PDGFRA could be an effective target to inhibit distant metastasis in advanced thyroid cancers. To translate this finding to the clinic, we used the most relevant multikinase inhibitor, imatinib, to inhibit PDGFRA signaling. The results showed that imatinib significantly suppressed cell growth, induced cell cycle arrest and cell death in SW579 cells. Our developed noninvasive apoptosis detection sensor (NIADS) indicated that imatinib induced cell apoptosis through caspase-3 activation. In conclusion, we believe that developing a specific and selective targeted therapy for PDGFRA would effectively suppress PDGFRA-mediated cancer aggressiveness in advanced thyroid cancers.

Transvaginal Reduction of a Heterotopic Cornual Pregnancy with Conservation of Intrauterine Pregnancy / 中国医学科学杂志(英文版)

Here we report a case of heterotopic cornual pregnancy after fertilization who was diagnosed at 6 weeks after frozen embryos transfer. The heterotopic pregnancy was successfully terminated by transvaginal ultrasound-guided selective fetal reduction. At 38+1 weeks, she underwent a cesarean section and delivered a healthy 3300 g male infant with Apgar score of 10-10' evaluated at 1 min and 5 min.

Evaluation of volume responsiveness by pulse pressure variability and inferior vena cava dispensability index at different tidal volumes by mechanical ventilation

This study investigated the effects of tidal volume (TV) on the diagnostic value of pulse pressure variation (PPV) and the inferior vena cava dispensability index (IVC-DI) for volume responsiveness during mechanical ventilation. In patients undergoing elective surgery with mechanical ventilation, different TVs of 6, 9, and 12 mL/kg were given for two min. The left ventricular outflow tract velocity-time integral (VTI) was measured by transthoracic echocardiography. The IVC-DI was measured at sub-xyphoid transabdominal long axis. The PPV was measured via the radial artery and served as baseline. Index measurements were repeated after fluid challenge. VTI increased by more than 15% after fluid challenge, which was considered as volume responsive. Seventy-nine patients were enrolled, 38 of whom were considered positive volume responsive. Baseline data between the response group and the non-response group were similar. Receiver operating characteristic curve confirmed PPV accuracy in diagnosing an increase in volume responsiveness with increased TV. When TV was 12 mL/kg, the PPV area under the curve (AUC) was 0.93 and the threshold value was 15.5%. IVC-DI had the highest diagnostic accuracy at a TV of 9 mL/kg and an AUC of 0.79, with a threshold value of 15.3%. When TV increased to 12 mL/kg, the IVC-DI value decreased. When the TV was 9 and 12 mL/kg, PPV showed improved performance in diagnosing volume responsiveness than did IVC-DI. PPV diagnostic accuracy in mechanically ventilated patients was higher than IVC-DI. PPV accuracy in predicting volume responsiveness was increased by increasing TV.

Establishment of a quantitative real-time PCR for rapid detection of Panax quinquefolius / 中国中药杂志

In this study, the specific primers and probes of Panax quinquefolius were designed for a quantitative real-time PCR, and the rapid identification method of P. quinquefolius was established by optimizing conditions. The method was used to validate 43 samples of the traditional Chinese medicine,and the results showed that 22 samples of P. quinquefolius were identified accurately. The limit of detection of the method can be reach to 1×10⁻⁴ ng. The method is accurate, fast, sensitive and specifically.

Phenylephrine effects on the morphology of osteoblasts and expression of nicotinamide phosphoribosyltransferase under oxidative stress / 中国组织工程研究

BACKGROUND: Phenylephrine has been proved to exert a protective effect on radiant-induced salivary gland and epithelial cell injuries, but its effect on hydrogen peroxide (H2O2)-induced oxidative stress in osteoblasts are not fully understood. OBJECTIVE: To explore the effect of phenylephrine on H2O2-induced oxidative stress in osteoblasts, and to explore the mechanism underlying the regulation by the expression level of nicotinamide phosphoribosyltransferase (Nampt). METHODS: Primary osteoblasts were cultured and randomly divided into four groups: blank control group, H2O2group, phenylephrine group, and combination group (0.5 hour pretreatment of 1×10-5mol/L phenylephrine, and then given 300 μmol/L H2O2). The morphology of osteoblasts was observed at different time points. Osteoblasts were collected after 24-hour culture, and total RNA and protein were then extracted to detect the mRNA and protein expression levels of Nampt by RT-PCR and western blot assay, respectively. RESULTS AND CONCLUSION: Compared with the blank control group, reduced osteoblasts and evident cell shrinks were observed in the H2O2group, while the number of osteoblasts significantly increased in the combined group compared with the H2O2group at 12, 24 and 48 hours of culture. RT-PCR results showed that the mRNA level of Nampt in the H2O2group was reduced by 31.23% of that in the blank control group, while the mRNA level of Nampt in the combination group was dramatically increased by 206.20% of that in the H2O2group at 24 hours of culture (both P < 0.05). Furthermore, western blot assay findings revealed that the protein level of Nampt in the H2O2group was reduced by 67.98% of that in the blank control group, while the protein level of Nampt in the combination group was increased by 152.25% of that in the H2O2group at 24 hours of culture (both P < 0.05). Our results indicate that phenylephrine can alleviate the shrink and atrophy of osteoblasts caused by H2O2, thereby exerting protective effect by up-regulating the mRNA and protein levels of Nampt that may be a regulatory gene.

Application of de-neurofilm in treatment of patellar arthritis with knee / 中国内镜杂志

Objective To investigate the curative effect of knee arthroplasty combined with denervation technique on knee patellofemoral arthropathy. Methods 60 patients with patellofemoral arthritis were selected from September 2009 to September 2015 for the study. All the patients were divided into observation group and control group by random number table. The patients in the control group were treated with arthroscopic treatment, and the patients in observation group were treated with arthroscopic cleaning and patellar biotherapy. The WOMAC score, the Lysholm score, and the Kujala score were compared between the two groups before and 3 months after surgery. Results There was no significant difference between the preoperative observation group and the control group (P > 0.05). The scores of WOMAC score, Lysholm score and Kujala score were higher in the observation group and the control group than those before the control group (P < 0.05 ). There were 2 cases of infection and 1 case of vascular nerve injury in 30 cases of postoperative 3 m observation group. One case of infection and 1 case of joint activity were restricted in 30 cases of control group. There was no significant difference in postoperative adverse reaction between the two groups (P > 0.05). Conclusions Given patellofemoral arthritis knee arthroplasty arthroscopy combined with patellar percutaneous nerve treatment can relieve pain, improve patellofemoral function and clinical efficacy, can be further popularized and used in clinical practice.

Application of de-neurofilm in treatment of patellar arthritis with knee / 中国内镜杂志

Objective To investigate the curative effect of knee arthroplasty combined with denervation technique on knee patellofemoral arthropathy. Methods 60 patients with patellofemoral arthritis were selected from September 2009 to September 2015 for the study. All the patients were divided into observation group and control group by random number table. The patients in the control group were treated with arthroscopic treatment, and the patients in observation group were treated with arthroscopic cleaning and patellar biotherapy. The WOMAC score, the Lysholm score, and the Kujala score were compared between the two groups before and 3 months after surgery. Results There was no significant difference between the preoperative observation group and the control group (P > 0.05). The scores of WOMAC score, Lysholm score and Kujala score were higher in the observation group and the control group than those before the control group (P < 0.05 ). There were 2 cases of infection and 1 case of vascular nerve injury in 30 cases of postoperative 3 m observation group. One case of infection and 1 case of joint activity were restricted in 30 cases of control group. There was no significant difference in postoperative adverse reaction between the two groups (P > 0.05). Conclusions Given patellofemoral arthritis knee arthroplasty arthroscopy combined with patellar percutaneous nerve treatment can relieve pain, improve patellofemoral function and clinical efficacy, can be further popularized and used in clinical practice.

Neuroendocrine tumors: analysis of 252 cases / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the epidemiology, diagnosis, and treatment status of neuroendocrine tumors (NETs) in our hospital.</p><p><b>METHODS</b>Medical records of 252 patients with neuroendocrine tumors diagnosed and treated in our hospital from January 1, 2004 to December 31, 2009 were collected and retrospectively reviewed in this study. The clinicopathological data including age of onset, initial symptoms, primary site, pathological conditions (Sny, CgA, Ki-67), disease stage at diagnosis, treatment, and follow up were analyzed.</p><p><b>RESULTS</b>The gender ratio M/F of the 252 cases was 1.9:1, with mean age of 55.2 years, and the high incidence was in age of 60-69 years. The tumors were located in the gastrointestinal tract (117 cases, 46.4%), broncho-pulmonary system (74 cases, 29.4%), other sites (61 cases, 24.2%) and unknown primary site (2 cases, 0.8%). Their first clinical symptoms vary, depending on the primary site. The common symptoms of primary rectal NETs were changes in bowel habits (29.3%) and diarrhea or constipation (17.5%), and most gastric NETs presented epigastric discomfort (86.4%). Most patients (71.4%) were diagnosed with stage I, II, III disease. Among the 252 cases, there were 110 carcinoids (43.7%), 108 neuroendocrine carcinomas (42.9%), 23 atypical carcinoids (9.1%), five neuroendocrine tumors (2.0%), four Merkel cell tumors (1.6%), and two composite carcinoids (0.8%). 206 patients (81.7%) received surgery, 39 (15.5%) received chemotherapy, and 31 cases (12.3%) were treated by palliative radiotherapy.</p><p><b>CONCLUSIONS</b>This single-center retrospective analysis of data demonstrated that males have a higher incidence rate than females. The most common primary sites of NETs are the digestive tract and lungs. The initial symptoms of NETs are different depending on their primary sites. Good prognosis can be achieved in the majority of patients after surgery, chemotherapy and palliative radiotherapy.</p>

Response of bone marrow mesenchymal stem cells to mechanical stretch and gene expression of transforming growth factor-beta and insulin-like growth factor-II under mechanical strain / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the response of rat bone marrow mesenchymal stem cells (MSCs) to a single period of mechanical strain and expression patterns of transforming growth factor-beta (TGF-beta) and insulin-like growth factor-II (IGF-II) after mechanical stretch.</p><p><b>METHODS</b>Bone marrow MSCs were isolated from SD rats and cultured in vitro. A four-point bending apparatus were used to perform a single period of mechanical strain (2000 microepsilon, 40 min) on MSCs. Cellular proliferation and alkaline phosphatase (ALP) activity of MSCs were examined and gene expression patterns of TGF-beta and IGF-II were detected by SYBR green quantitative real-time RT-PCR.</p><p><b>RESULTS</b>Cell proliferation, ALP activity and expression of TGF-beta and IGF-II were all significantly up-regulated in stretched MSCs when compared with their controls. The mRNA levels of TGF-beta and IGF-II got top increase immediately after mechanical loading and increased about 51.44 and 8.92 folds, respectively, when compared with control cells. Expression of TGF-beta and IGF-II decreased with time and returned to control level at 12 h after mechanical stimulus, despite of a small increase at 6 h.</p><p><b>CONCLUSION</b>The mechanical stretch can promote MSCs proliferation, up-regulate its ALP activity and induce a time-dependent expression increase of TGF-beta and IGF-II which in turn result in osteogenic differentiation of MSCs. Mechanical stimulus is a key stimulator for osteogenic differentiation of MSCs and vital for bone formation in distraction osteogenesis.</p>

Osteoblastic differentiation and gene expression profile change in rat bone marrow mesenchymal stem cells after a single period of mechanical strain / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the osteoblastic differentiation and compare the difference in the gene expression of rat bone marrow mesenchymal stem cells (MSCs) affected by a single period of mechanical strain.</p><p><b>METHODS</b>Bone marrow MSCs were harvested from the femurs and tibiae of SD rats and cultured in vitro. A four-point bending apparatus were used to perform a single 40-minute period of 2,000 microepsilon mechanical strain on these MSCs. The proliferation of the MSCs was tested by MTT on scheduled date, and the osteoblastic differentiation of the MSCs was measured by testing the expression of osteocalcin and alkaline phosphate (ALP) activity of these cells. In addition, we have investigated the possible mechanisms underlying the action of the single 40-minute period of 2,000 microepsilon mechanical strain on these MSCs, after profile blotted and handled by bioinformation, the gene expressions of these two periods of MSCs were examined.</p><p><b>RESULTS</b>The MSCs have grown well in vitro. Our experiment showed that mechanical environment did not weaken the proliferation of the MSCs. However, the ALP activity and the expression of osteocalcin were significantly up-regulated by the 2,000 microepsilon mechanical strain. Using the 27 K Rat Genome Array, 416 different expressions were found. The rate of different genes was 2.8%, of which the expressions of 247 genes increased (61 genes remarkably increased) and 169 genes decreased (74 genes remarkably decreased) in these two periods of MSCs.</p><p><b>CONCLUSION</b>Mechanical strain induced the osteoblastic differentiation of the MSCs, which may be attributed to the different gene levels.</p>

Expression of bone-related genes in bone marrow MSCs after cyclic mechanical strain: implications for distraction osteogenesis / 国际口腔科学杂志·英文版

<p><b>AIM</b>Understanding the response of mesenchymal stem cells (MSCs) to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis.</p><p><b>METHODOLOGY</b>In this study, a single period of cyclic mechanical stretch (0.5 Hz, 2,000 microepsilon) was performed on rat bone marrow MSCs. Cellular proliferation and alkaline phosphatase (ALP) activity was examined. The mRNA expression of six bone-related genes (Ets-1, bFGF, IGF-II, TGF-beta, Cbfa1 and ALP) was detected using real-time quantitative RT-PCR.</p><p><b>RESULTS</b>The results showed that mechanical strain can promote MSCs proliferation, increase ALP activity, and up-regulate the expression of these genes. A significant increase in Ets-1 expression was detected immediately after mechanical stimulation, but Cbfa1 expression became elevated later. The temporal expression pattern of ALP coincided perfectly with Cbfa1.</p><p><b>CONCLUSION</b>The results of this study suggest that mechanical strain may act as a stimulator to induce differentiation of MSCs into osteoblasts, and that these bone-related genes may play different roles in the response of MSCs to mechanical stimulation.</p>

Epidemiology and current status of asthma and associated allergic diseases in Taiwan- ARIA Asia-Pacific Workshop report.

The prevalence of allergic diseases appears to have been increasing in recent years. The hospitalization rate of asthma in children showed an increasing trend. House dust mites and cockroaches are the two most common indoor aeroallergens in Taiwan. Various kinds of inhaled corticosteroids or combination medications are available, but in clinical practice these have not been used as much as oral beta-2 agonists. Generally 68% of the physicians would follow the asthma treatment guidelines. Because of the comprehensive health care insurance system, the majority of the population in Taiwan can afford the medical expense of diseases. The country's expenditure of asthma care is around USD 83.1 millions per year which is increasing by the year as well. In clinical aspects, asthma education should still be included as part of its treatment.

Prevalence and severity of symptoms of asthma, allergic rhinitis, and eczema in 10- to 15-year-old schoolchildren in central Taiwan.

The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was distributed through 14 schools and was completed by 11,874 students out of which are parents of 4,167 children aged between 10 and 12 years old and 7,677 older children aged between 13 and 15 years in central Taiwan. The overall cumulative and 12-month prevalence of wheezing, rhinitis, and eczema were 7.4%, 43.0%, and 7.2%, respectively. It was shown that boys had significantly higher prevalence of wheezing and rhinitis (p < 0.001 and p = 0.001) when compared to girls in central Taiwan. The study also found that prevalence rates among younger children with symptoms of wheezing, rhinitis, and recurrent itchy rash in the past 12-month (8.2%, 44.4%, and 8.8%) were higher than that among older children (6.9%, 42.2%, and 6.3%, respectively). In conclusion, boys had significantly higher prevalence of wheezing and rhinitis than girls while younger children tend to have higher prevalence of the disorders than those that are older in age.

Increasing asthma care knowledge and competence of public health nurses after a national asthma education program in Taiwan.

One of the responsibilities of a public health nurse is to provide asthma education to local residents. However, there have been no comprehensive education programs for public health nurses on asthma care in the past. This study aimed to determine level of competence of public health nurses on asthma care in order to improve their capability through a one-day national asthma education course. In addition to lectures on updated asthma management information, data was obtained through demonstrations and practice on inhalation techniques of various kinds of inhaled devices, including the ability to use and interpret the data of a peak flow meter. Two written examinations with the same questions were given to participants before and right after the lectures. All of the 560 public health nurses in the 392 public health bureaus were invited to join the program and 522 (93.2%) participated. Five hundred and six completed both the pre- and post-tests. Before the national education program, only 10.9% of the participants knew the purpose of the peak flow meter, while 62.6% had never heard of it. Initially, they showed less confidence on teaching patients on the use of inhaled devices (2.36 and 2.59 in 5 scales). Comparing the two tests, there was a significant increase in the public nurses' knowledge as regards: 1) the general concept of asthma, 2) prevention of trigger factors and environmental control, 3) proper medication knowledge, 4) peak flow meter (PEF) monitoring, and 5) intervention after acute exacerbation of asthma (p < 0.001). A well-designed course on asthma management is an efficient scheme to improve public health nurses' knowledge and confidence on asthma care.

Survey of the clinical practice of physicians in the management of asthma in Taiwan.

Asthma is a common problem with a prevalence rate increasing every year. However, not all asthmatic patients receive appropriate treatment, partly due to the disease entity or patients' compliance, and partly due to physicians' knowledge and disposition in terms of treatment. This study was designed to investigate the current status of asthma treatment among clinicians in different practice settings, particularly regarding the acceptance of and adherence to asthma treatment guidelines and asthma patient education. Questionnaires were distributed by randomized sampling to doctors throughout the entire country. The questionnaire had six parts, measuring the following: 1) the use of different kinds of medication in the treatment of asthma; 2) adherence to asthma treatment guidelines; 3) the use of inhaled corticosteroids as part of management; 4) the use of peak flow meters in monitoring asthma; 5) relative efficiency in treating asthma; and 6) the use of a referral system, from general practitioners to specialists. There were 531 respondents out of 1,000 questionnaires distributed. The results revealed the following: 1) 20.2% of physicians use oral corticosteroids for maintenance therapy; 2) 31.8% of physicians do not follow asthma treatment guidelines; 3) 77.2% of physicians use inhaled corticosteroids for maintenance therapy (physicians in medical centers and regional hospitals use inhaled corticosteroids more frequently than private practitioners); 4) 51% of doctors do not use peak flow meters to monitor asthma symptoms because of prohibitive costs; 5) approximately 80% of clinicians have confidence in dealing with asthma problems; and 6) 29.2% of general practitioners do not refer patients to asthma specialists unless there is poor control or a need for further evaluation. Adherence to asthma treatment guidelines is poor, and such guidelines need to be popularized or simplified. There are still many discrepancies among doctors at different levels of hospitals. Re-education and review of asthma knowledge is necessary to keep clinical practitioners at the forefront of standard practice.

The changes of cytoskeleton F-actin in rat bone marrow mesenchymal stem cells and calvarial osteoblasts under mechanical strain / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To explore the response of rat bone marrow mesenchymal stem cells (MSCs and calvarial osteoblasts to mechanical strain and the consequent changes of cytoskeleton F-actin.</p><p><b>METHODS</b>Bone marrow MSCs and calvarial osteoblasts were isolated from SD rats and cultured in vitro. Mechanical stretch was performed on passage 3 cells at 2 000 microepsilon for 0, 2, 6 and 12 hours using four-point bending system. The response of cells and the distribution of F-actin were observed using fluorescent staining under laser scanning confocal microscope and the morphological parameters were quantified using image analysis software Laserpix.</p><p><b>RESULTS</b>Under mechanical stretch, the fluorescent staining decreased obviously at both MSCs and osteoblasts, and F-actin filaments were rearranged and became tenuous, thinner, and abnormally distributed. The outline of nucleus became unclear and apoptotic changes were observed at some of both cells. Cellular size decreased more significantly in MSCs than in osteoblasts. Quantity analysis showed that total area of cells, total fluorescent density and green fluorescent density (F-actin) were all significantly decreased in MSCs (P < 0.05 or P < 0.01), and total fluorescent density, green fluorescent density and red fluorescent density (nuclei) did also in osteoblasts (P < 0.05 or P < 0.01).</p><p><b>CONCLUSION</b>Mechanical stretch caused extensive response on both MSCs and osteoblasts which led to the rearrangement of F-actin filament and apoptosis in some of these cells. MSCs were more sensitive to mechanical strain than osteoblasts.</p>

Detection of Ampicillin - Resistant Genes and Studies on the Molecular Mechanisms of Ampicillin - Resistant Haemophilus Influenzae / 实用儿科临床杂志

Objective To study the molecular mechanisms of ampicillin- resistant haemophilius influenzae (Hi)in Nanjing. Methods One hundred and fifty- eight strains of Hi isolated from children were collected to detect bata-lactamase. TEM and ROB bata- lacta-mase genes were detected by polymerase chain reaction (PCR) ,and cloned into T vector for sequencing. Results The rate of ampicillin resistance was 41. 77% in Hi isolated from children in Nanjing,40.51 % was found to be bata-lactamase production. Eighty-nine strain were TEM positives, 1 strain was ROB positive,63 strains bata - lactamase positive ampicillin- resistant Hi were identified. The resistance mechanism of ampicillin resistant Hi was production of bata - lactamase , mainly TEM - type enzyme. Two bata - lactamase negative ampicillin - resistant Hi were identified , predicts the other mechanisms of ampicillin - resistant Hi was occuered yet . One strain of non -TEM - type,and non - ROB - type bata - lactamase - producing Hi was identified. Conclusions Ampicillin - resisitant in Hi isolated from children in this region is challenging. TEM bata - lactamase is the principal mechanism of ampicillin - resistant of Hi.