Effects of parameters of BiPAP ventilator on compliances of chest and lung,and arterial blood gas indexes of AECOPD patients / 中国医学装备

Objective:To explore the effects of ventilator parameters on the compliances of chest and lung,and arterial blood gas indicators of patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD)when biphasic positive airway pressure(BiPAP)ventilation treated AECOPD patients at acute exacerbation period.Method:A total of 78 AECOPD patients who underwent non-invasive ventilation treatment by using BiPAP ventilators in Xinjiang Cardiovascular and Cerebrovascular Hospital from April 2020 to April 2021 were selected.The common range of inspiratory positive airway pressure(IPAP)was 10-25 cmH2O.Based on the specific situation and adjustment of clinical needs of patients,this study set"<15 cmH2O"as the low IPAP group(n=34),and set"≥15 cmH2O"as the high IPAP group(n=44)to analyze the correlation between IPAP of BiPAP ventilator parameters and the therapeutic effects,chest lung compliances and arterial blood gas indicators of patients.Results:The rate of therapeutic effect of patients in the high IPAP group was 93.48%,which was significantly higher than 71.88%of the low IPAP group,and the difference between the two groups was statistically significant(x2=6.766,P<0.05).Before treatment,there were no statistically significant differences in indicators included chest compliance(CTh),lung compliance(CL)and total compliance(Ct)between the two groups(P>0.05).After treatment,the Ct,CL and CTh of patients in the high IPAP group were significantly higher than those in the low IPAP group,and the differences between the two groups were statistically significant(t=2.508,2.027,2.185,P<0.05),respectively.There was no statistically significant difference in arterial oxygen partial pressure(PaO2)value between the two groups before used mechanical ventilation(P>0.05).The PaO2 values of patients at 2,4,6 and 8h of using mechanical ventilation in the high IPAP group were significantly higher than those in the low IPAP group,and the differences between different groups were statistically significant(t=8.531,5.296,3.264,4.623,P<0.05),respectively.Both two groups of patients showed a significant increase in inflammatory mediators such as matrix metalloproteinase-9(MMP-9)and interleukin-8(IL-8)during occurring disease.After treatment,the levels of the two mediators decreased,and the high IPAP group was significantly lower than that of low IPAP group(t=2.251,5.484,P<0.05),respectively.The incidence of abdominal distension in patients of high IPAP group was 20.45%,which was significantly higher than 5.88%of low IPAP group,and the difference between groups was statistically significant(x2=3.623,P<0.05).Conclusion:The IPAP of BiPAP ventilator parameters has effect on chest lung compliance,arterial blood gas analysis and inflammatory indicators in AECOPD patients.High IPAP can improve therapeutic effect,and improve chest lung compliance and arterial blood gas analysis,but can easily cause adverse reactions such as abdominal distension.

Analysis of Various Histopathological Patterns in Pleomorphic Adenoma - An Institutional Case Study

Introduction: Pleomorphic adenoma, the most common benign mixed salivary gland tumor which accounts for 70-80%, is a biphasic tumor with dual origin from epithelial and myoepithelial elements. It shows a malignant transformation rate of 6%. Microscopically, pleomorphic adenoma characteristically displays vast morphologic diversity. This present study is done to analyze prevalence rates and histomorphological variations to better elucidate the pattern of occurrence, diagnosis and treat- ment plan of pleomorphic adenoma. Materials and Methods: This are a retrospective study which was conducted in a private institution, Chennai. Based on the proportion of parenchymal and stromal tumor components, the cases were classified into four subtypes as proposed by Foote and Frazell. Morphological patterns, cellular patterns, capsular alterations and Stromal components were analyzed and statisti- cally evaluated. Results: Our analysis showed an overall 0.87% of pleomorphic adenoma cases being reported were associated with minor salivary glands followed buccal mucosa and palate. All the reported cases showed Type II pattern with histological cellular pat- tern of spindle cells and ductal morphological pattern. Conclusion: We observed the great diversity of morphological aspects of the stroma in pleomorphic adenoma, in which many cases showed variation in morphology and cellularity associated with tumor location.

Biphasic squamoid alveolar renal cell carcinoma: A rare entity with an even rarer presentation as cutaneous metastases – A case report

Biphasic squamoid alveolar renal cell carcinoma (BSARCC) is a newly emerging distinct and rare morphologic variant of renal cell carcinoma (RCC). Morphological, immunohistochemical, and molecular data have shown that BSARCC is closely related to papillary RCC type 1. We report a case of Biphasic squamoid alveolar renal cell carcinoma with a rare presentation as cutaneous metastases. This variant tends to show an aggressive behavior. Hence, accurate histopathological diagnosis can help in effective treatment and for close follow-up of the patients.

Enfrentamiento de la anafilaxia en el servicio de urgencia / Approach of Anaphylaxis in the emergency room

La anafilaxia es una reacción en su mayoría de hipersensibilidad tipo I, que estimula la activación generalizada de mastocitos, y provoca un cuadro clínico multisistémico que puede ser fatal. Se estima que tiene una incidencia de 0,03-0,1% y una prevalencia de vida de 0,5-2% en la población general. Generalmente, la reacción inmunológica ocurre posterior a la ingesta de alimentos, uso de medicamentos o picaduras de insectos, pero también se han descrito mecanismos no inmunológicos (no IgE) que actúan directamente sobre los mastocitos, llamadas en la literatura "reacciones anafilactoideas". La anafilaxia fue descrita por Paul Portier y Charles Robert Richet en 1902 en perros, los cuales desarrollaban esta reacción posterior a la inyección repetida de veneno de anémonas (medusas). Sin embargo, esta entidad no tuvo criterios diagnósticos ni pilares de manejo estructurado hasta el año 2006. En ese año en se publicó el segundo simposio de manejo de la anafilaxia, en donde se definieron criterios diagnósticos clínicos claros y el rol fundamental de la adrenalina en su manejo; la única droga que cambia el pronóstico del paciente.

Anaphylaxis is mainly a type I hypersensitivity reaction. It triggers a widespread activation of mast cells, causing a multisystemic clinical scenario that can be fatal. It is estimated to have an incidence of 0.03-0.1% and a lifetime prevalence of 0.5-2%. Most immunological reactions occur after food ingestion, medication, or insect stings, but non-immunological (non-IgE) mechanisms that act directly on mast cells, called Anaphylactoid Reactions, have been also described. Anaphylaxis was described by Paul Portier and Charles Robert Richet in 1902 in dogs, that developed this disease after repeated injections of anemones (jellyfish) venom. However, this entity didn't have established diagnostic criteria or an standarized management until 2006. In this year, the second anaphylaxis management sym-posium took place and clear clinical diagnostic criteria were defined. The fundamental role of adrenaline in its management was also established. The former is the only drug that has demonstrated to improve prognosis of the patient

Molecular dynamics simulation of force-regulated interaction between talin and Rap1b / 生物医学工程学杂志

The binding of talin-F0 domain to ras-related protein 1b (Rap1b) plays an important role in the formation of thrombosis. However, since talin is a force-sensitive protein, it remains unclear whether and how force regulates the talin-F0/Rap1b interaction. To explore the effect of force on the binding affinity and the dynamics mechanisms of talin-F0/Rap1b, molecular dynamics simulation was used to observe and compare the changes in functional and conformational information of the complex under different forces. Our results showed that when the complex was subjected to tensile forces, there were at least two dissociation pathways with significantly different mechanical strengths. The key event determining the mechanical strength difference between the two pathways was whether the β4 sheet of the F0 domain was pulled away from the original β1-β4 parallel structure. As the force increased, the talin-F0/Rap1b interaction first strengthened and then weakened, exhibiting the signature of a transition from catch bonds to slip bonds. The mechanical load of 20 pN increased the interaction index of two residue pairs, ASP 54-ARG 41 and GLN 18-THR 65, which resulted in a significant increase in the affinity of the complex. This study predicts the regulatory mechanism of the talin-F0/Rap1b interaction by forces in the intracellular environment and provides novel ideas for the treatment of related diseases and drug development.

Clinical-imaging features and prognoses of 8 children with acute encephalopathy combined with biphasic seizures and late reduced diffusion / 中华神经医学杂志

Objective:To summarize the clinical-imaging features and prognoses of acute encephalopathy combined with biphasic seizures and late reduced diffusion (AESD).Methods:A retrospective analysis was performed. The clinical and imaging data and follow-up results of 8 children with AESD, admitted to Departments of Neurology and Rehabilitation Medicine, Wuhan Children's Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology from January 2020 to April 2022 were collected.Results:The antecedent infections in 8 children were predominantly gastrointestinal and respiratory tract infections and convulsive seizures occured within 24 h of fever. The clinical presentation was biphasic: 3 had sustained convulsive state in the first phase of the disease, and all showed cluster seizures with worsening impairment of consciousness in the second phase of the disease, including 4 with involuntary movements during recovery from the disease. Seven children required admission to Intensive Care Unit, 4 required tracheal intubation for assisted ventilation, and 1 was combined with septic shock. Brain MRI findings of 8 children were "bright tree" in the second phase of the disease, including bilateral symmetrical and bilateral asymmetrical involvements, with diffuse and focal involvements. All 8 children were treated with glucocorticoids and/or gammaglobulin, and 2 were given mild hypothermia brain protection. Follow-up was performed for more than 3 months, and brain MRI indicated cerebral atrophy, subdural effusion and cerebral malacia. All the 8 children survived with different degrees of sequelae. Two children had Extended Glasgow Outcome Scale scores of 4, 4 had scores of 5, and 2 had scores of 7.Conclusion:AESD is a special clinical-maging syndrome, characterized by biphasic seizure and "bright tree" on head MRI; the survival is high, but neurological sequelae of different degrees are easily left behind.

Spindle Cell Carcinoma: A Confirmatory Diagnostic Analysis by Immunohistochemical Studies

Introduction: WHO defines it as a ‘‘carcinoma within which there are some elements resembling a squamous cell carcinoma that are admixed with a spindle cell component. Spindle cell carcinoma is an uncommon poorly differentiated type of SCC com- prising up to 3% of SCC and it is also known as sarcomatoid carcinoma which is a rare biphasic malignant neoplasm. . Case Report: A 20 year old female patient complains of pain and growth in lower front teeth region since 3 months and gave a history of growth 2yrs back in the front teeth region for which she has been operated but it has recurred again. Discussion: The histological features mimicked other connective tissue sarcomas & spindle cell malignancies at light micro- scopic level. Hence, after undergoing immunohistochemistryA careful study based on clinical, radiological and histopathologi- cal and immunohistochemical examination was done and a final diagnosis of spindle cell carcinoma was given.

Novel biopharmaceutical development investigations towards drug and formulation performance optimization

For a drug to excerpt pharmacological action after oral intake, it first needs to be released from the formulation, get into solution (dissolve), be absorbed, and reach the systemic circulation. Since only solubilized drugs can be absorbed, and thus have therapeutic effect, the understanding of the dissolution and drug release processes of a drug product is of primary importance. Such understanding allows a robust formulation development with an ideal in vivo performance. In order to meet set standards, the performance assessment of oral drug products, such as dissolution testing, often applies conditions that are not reflective of the in vivo environment. The use of non-physiologically relevant dissolution method during the drug product development phase can be misleading and give poor mechanistic understanding of the in vivo dissolution process. Hence, we hypothesized that applying physiologically relevant conditions to the dissolution test would result in more accurate in vivo predictability for a robust and precise development process. Since the buffering system in the intestinal lumen operates at low molarity values, phosphate buffer at low buffer capacity was used as a first approach to an in vivo relevant parameter. Furthermore, a biphasic system was used, that is, the low buffer capacity medium was paired with an organic layer (n-octanol) to mimic the concurrent drug absorption that happens with the in vivo dissolution. Both poorly and highly soluble drugs in immediate release formulations (ibuprofen and metronidazole, respectively) were tested in this set-up to assess the dissolution in the aqueous medium and the partitioning to the organic phase. Additionally, enteric coated formulations were tested in bicarbonate buffer at the in vivo reported molarities values to assess the impact of buffer species on drug dissolution. The evaluated parameters were the buffer system (bicarbonate buffer vs. phosphate buffer), buffer capacity and medium pH. In all approaches, dissolution was also carried out in compendial buffer for comparison purposes. Our results demonstrate that the USP-recommended dissolution method greatly lacked discriminatory power, whereas low buffer capacity media discriminated between manufacturing methods. The use of an absorptive phase in the biphasic dissolution test assisted in controlling the medium pH due to the drug removal from the aqueous medium. Hence, the applied noncompendial methods were more discriminative to drug formulation differences and manufacturing methods than conventional dissolution conditions. In this study, it was demonstrated how biphasic dissolution and a low buffer capacity can be used to assess drug product performance differences. This can be a valuable approach during the early stages of drug product development for investigating drug release with improved physiological relevance. Similarly, all the enteric coated formulations displayed a fast release in phosphate buffer and complied with the compendial performance specifications. On the other hand, they all had a much slower drug release in bicarbonate buffer and failed the USP acceptance criteria. Also, the nature of the drug (acid vs base) impacted the dissolution behavior in bicarbonate buffer. This study indicates that compendial dissolution test for enteric coated tablets lacks physiological relevance and it needs to be reevaluated. Thus, an in vivo relevant performance method for EC products is needed. Overall, the findings of this thesis comprehensively demonstrates that meaningful differences in performance and accordance to clinical reports were only obtained when physiological relevant conditions were applied. Hence, our results indicate that the central hypothesis was answered positively

Para que um medicamento exerça a ação farmacológica após a ingestão oral, ele primeiro precisa ser liberado da formulação, dissolver, ser absorvido e atingir a circulação sistêmica. Uma vez que apenas medicamentos solubilizados podem ser absorvidos e, assim, ter efeito terapêutico, a compreensão dos processos de dissolução e liberação de um medicamento é de extrema importância. Tal compreensão permite o desenvolvimento de uma formulação robusta com o desempenho in vivo ideal. Para atender aos padrões regulatórios previamente estabelecidos, a avaliação da performance de formulações orais, como por exemplo, o teste de dissolução, frequentemente aplica condições que não refletem o ambiente fisiológico. O uso de métodos de dissolução não fisiologicamente relevante durante a fase de desenvolvimento do medicamento pode gerar resultados equivocados sem uma compreensão mecanistica do processo de dissolução in vivo. Portanto, a hipótese desse trabalho é que a aplicação de condições fisiologicamente relevantes no teste de dissolução resultaria em uma predição mais precisa da dissolução in vivo para um processo de desenvolvimento robusto e preciso. Uma vez que o sistema tampão no lúmen intestinal possui baixa molaridade, o tampão fosfato com baixa capacidade tamponante foi usado como uma primeira abordagem como um meio de dissolução fisiologicamente relevante. Além disso, foi utilizado um sistema bifásico, ou seja, o meio de baixa capacidade tamponante combinado a uma fase orgânica (n-octanol) para imitar a absorção in vivo. Formulações de liberação imediata contendo fármacos de baixa e de alta solubilidade (ibuprofeno e metronidazol, respectivamente) foram testadas no sistema bifásico para avaliar a dissolução no meio aquoso e a partição para a fase orgânica. Ademais, formulações com revestimento entérico foram testadas em tampão bicarbonato nos valores de molaridades fisiológicos para avaliar o impacto da espécie tamponante na dissolução do fármaco. Os parâmetros avaliados foram o sistema tampão (tampão bicarbonato vs. tampão fosfato), capacidade tamponante e pH médio. Em todas as abordagens, a dissolução também foi realizada em tampão farmacopeico para fins de comparação. Nossos resultados demonstraram que o método de dissolução farmacopeico não foi discriminativo, enquanto o meio com menor capacidade tamponante diferenciou entre as formulações obtidas via granulação úmida ou compressão direta. Ademais, a utilização da fase orgânica no teste de dissolução bifásica auxiliou no controle do pH do meio aquoso. Portanto, os métodos não compendiais aplicados foram mais discriminativos do que as condições de dissolução convencionais. Neste estudo, foi demonstrado como a dissolução bifásica e uma baixa capacidade tamponante podem ser usadas para avaliar as diferenças na performance de formulações. Esta pode ser uma abordagem valiosa durante os estágios iniciais do desenvolvimento de medicamentos para investigar a liberação destes sob condições fisiologicamente relevantes. Da mesma forma, todas as formulações com revestimento entérico exibiram uma liberação rápida em tampão de fosfato e atenderam às especificações farmacopeicas. Entretanto, a liberação do fármaco foi muito mais lenta em tampão de bicarbonato e consequentemente não cumpriram com as especificações farmacopeicas. Além disso, a natureza do fármaco (ácido vs. base) impactou o comportamento de dissolução no tampão de bicarbonato. Este estudo indica que o teste de dissolução convencional para comprimidos de liberação retardada não possui relevância fisiológica e precisa ser reavaliado. Portanto, os resultados desta tese demonstram de forma abrangente que diferenças significativas na performance condizentes com relatórios clínicos foram obtidas apenas quando as condições fisiológicas relevantes foram aplicadas. Esses resultados indicam que a hipótese central foi respondida positivamente

Synthesis and in Vitro Toxicity Assessment of Different Nano-Calcium Phosphate Nanoparticles

Abstract Nanoscale biomaterials are commonly used in a wide range of biomedical applications such as bone graft substitutes, gene delivery systems, and biologically active agents. On the other hand, the cytotoxic potential of these particles hasn't yet been studied comprehensively to understand whether or not they exert any negative impact on the cellular structures. Here, we undertook the synthesis of beta-tricalcium phosphate (ß-TCP) and biphasic tricalcium phosphate (BCP) nanoparticles (NPs) and determine their concentration-dependent toxic effects in human fetal osteoblastic (hFOB 1.19) cell line. Firstly, BCP and β-TCP were synthesized using a water-based precipitation technique and characterized by X-Ray Diffraction (XRD), Raman Spectroscopy, and Transmission Electron Microscopy (TEM). The cytological effects of β-TCP and BCP at different concentrations (0-640 ppm) were evaluated by using 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. The total oxidative status (TOS) parameter was used for investigating oxidative stress potentials of the NPs. In addition, the study assessed the DNA damage product 8-hydroxy-2′-deoxyguanosine (8-Oxo-dG) level in hFOB 1.19 cell cultures. The results indicated that the β-TCP (above 320 ppm) and BCP (above 80 ppm) NPs exhibited cytotoxicity effects on high concentrations. It was also observed that the oxidative stress increased relatively as the concentrations of NPs increased, aligning with the cytotoxicity results. However, the NPs concentrations of 160 ppm and above increased the level of 8-OH-dG. Consequently, there is a need for more systematic in vivo and in vitro approaches to the toxic effects of both nanoparticles.

Reactive aqueous two-phase systems for the production and purification of PEGylated proteins

BACKGROUND PEGylation, defined as the covalent attachment of polyethylene glycol, allows the synthesis of PEGylated therapeutic proteins with enhanced physicochemical properties. Traditional alkylating Nterminal PEGylation reactions on amine groups involve the use of modified linear mono-methoxy polyethylene glycol (mPEG) molecules looking for the synthesis of mono-PEGylated products. However, this approach requires different purification steps since inevitably undesired cross-linked products are synthesized. Herein, we propose the use of reactive aqueous two-phase systems (ATPS) to produce and purify PEGylated therapeutic conjugates using Ribonuclease A (RNase A) as a model protein. RESULTS: Selected linear 5 kDa and 20 kDa mPEG ­ potassium phosphate systems were produced according to equilibrium data obtained from constructed binodal curves. All reactive systems were able to generate biphasic systems and to PEGylate RNase A. Two 5 kDa and two 20 kDa systems were selected based on the reaction yield percentage and the feasibility of purifying the mono-PEGylated RNase A from the diPEGylated and native RNase A by contrasting the differences in their partition behaviors. The remnant biological activity was of 94% and of 100% for the mono-PEGylated RNase A purified from the 5 kDa and 20 kDa mPEG systems when compared to the mono-PEGylated conjugate obtained by standard procurement methods.

Biphasic dissolution test and its application in the evaluation of poorly soluble drug preparations / 药学学报

Biphasic dissolution test, consisting of immiscible aqueous and organic phase, is an in vitro dissolution method that simultaneously measures the dissolution and partition of drugs. Due to the advantages of simulating in vivo absorption and overcoming the influence of surfactants on dissolution, it has been widely used to evaluate the poorly soluble drugs in vitro dissolution. Based on the relevant research in this field in recent years, this review summarizes the history, dissolution device, theoretical model and application of the biphasic dissolution test. Finally, the prospects in the development of biphasic dissolution test are also outlined.

Biphasic calcium phosphate loaded with advanced platelet rich fibrin can promote the activity of rabbit bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND: Adding growth factor to scaffold material can promote the proliferation and osteogenic differentiation of cultured stem cells in vitro and promote bone tissue regeneration. Advanced platelet rich fibrin (A-PRF) contains a variety of growth factors, which can promote the proliferation activity of a variety of cells and the expression of related functional proteins. OBJECTIVE: To observe the effects of the sole and combined usage regarding A-PRF and biphasic calcium phosphate (BCP) on the growth of bone marrow mesenchymal stem cells. METHODS: The third generation of rabbit bone marrow mesenchymal stem cells was cultured in four groups, including basic medium (blank group), A-PRF condition medium (A-PRF group), BCP (BCP group), A-PRF condition medium and BCP (A-PRF+BCP group). Cell proliferation activity was detected by CCK-8 assay. Cell adhesion was observed based on methylrhodamine-phalloidin fluorescence staining. Intracellular alkaline phosphatase expression and mineralized nodules were quantitatively measured. RESULTS AND CONCLUSION: (1) The absorbance value of proliferation of the A-PRF+BCP group was higher than that of the other three groups at 3, 5, 7, 11 and 14 days after culture. The absorbance value of proliferation of cells cultured in the A-PRF group was higher than that of the BCP group and the blank group at 1, 3 and 5 days after culture. The absorbance value of proliferation of BCP group was higher than that of the A-PRF group and the blank group at 7, 11 and 14 days after culture. (2) Methylrhodamine-phalloidin fluorescence staining showed that bone marrow mesenchymal stem cells in the BCP group and the A-PRF+BCP group adhered to the surface of BCP and the number of cells and microfilaments in the A-PRF+BCP group was higher than that in BCP group. (3) The synthesis of mineralized nodules was A-PRF+BCP group > BCP group > A-PRF group > blank group at 1, 21 and 28 days after surgery. (4) The expression of alkaline phosphatase was A-PRF+BCP group > BCP group > A-PRF group > blank group at 5, 7 and 9 days. There was significant difference between the two groups (P < 0.05). (5) The results showed that BCP exerted a weak influence on promoting cell proliferation in the early stage, but its effect of scaffold was apparent. A-PRF had a significant effect on promoting cell proliferation with considerable influence on promoting cell proliferation and differentiation when combined BCP.

Safety and effectiveness of a biosimilar biphasic insulin in the management of diabetes mellitus during routine clinical practice in Asian patients

@#Introduction: Biosimilar insulins have the potential to increase access to treatment among patients with diabetes mellitus (DM), reduce treatment costs, and expand market competition. There are no published studies evaluating the performance of biosimilar insulins in routine clinical practice in Asia. This study assessed the safety and effectiveness of biphasic isophane insulin injection in Malaysian DM patients. Materials and Methods: In this open label, single-arm, observational, post marketing study, patients received biphasic isophane insulin injection as per the Prescribing Information; and were assessed for safety (adverse events including hypoglycaemia), effectiveness (glycosylated haemoglobin [HbA1c]; fasting blood sugar, [FBS]; and patient’s condition by patient and physician) over a period of 24 weeks. Results: Adult male and female diabetes patients (N=119; type 2 DM, n=117) with a mean (SD) diabetes duration of 13 years were included. No new safety signals have been identified. Significant reduction in HbA1c was observed at weeks 12 and 24 (mean [SD] - baseline: 9.6% [1.9]; Week 12: 9.0% [1.7] and at Week 24: 9.1% [1.7]; p < 0.001). There were 10 serious and 9 non-serious adverse events reported in the study. Expected mild events included hypoglycaemia and injection site pruritus. However, the majority of the adverse events were non-study drug related events. No deaths were reported during the study. Discussion: Biphasic isophane insulin injection was well tolerated with no new safety concerns. It was found effective in post- marketing studies conducted in routine clinical settings when administered in DM patients in this study.

Significance of Abnormal T Waves in Acute Coronary Syndrome without ST Changes in ECG

T-wave abnormalities are common electrocardiographic occurrences in patients with acute coronary syndromes. The clinical and electrocardiographic course and angiographic findings in patients with evolving inverted or biphasic T waves have not been fully elucidated. Patients with abnormal T waves associated with unstable angina represent a subgroup with a high probability of near total obstruction of coronary artery and myocardial dysfunction. In the present study we describe a subgroup of patients with myocardial ischemia who during the acute Ischemic phase did not develop elevation but only biphasic or inverted T waves in the ECG and had >90% stenosis of 1 or more coronary arteries. Methods: The study comprised 125 patients presented with unstable angina pectoris. Patients’ characteristics, Electrocardiographic Data, Cardiac enzymes and Coronary angiography findings were obtained. Collected data was analyzed and sensitivity, specificity, positive predictive value, significance of test (p value) were calculated using appropriate statistical method. Results: Of the 125 patients deep symmetrical and sustained T-wave inversions were present in 72 patients & biphasic T-waves in 28 patients. 125 patients underwent coronary angiography, 92(74%) patients had >90% stenosis of 1 or more coronary arteries; sensitivity of abnormal T waves for significant stenosis was 90%, specificity 92%, positive predictive value 97.83 % and p value <0.001. Conclusion: We have identified a subgroup of patients with critical obstruction of coronary artery in patients with unstable angina and non diagnostic ECG T-wave abnormalities are significant electrocardiographic occurrences in patients with acute coronary syndromes and frequently associated with coronary artery obstruction

Adjunctive hyperbaric oxygen therapy for irradiated rat calvarial defects

PURPOSE: The aim of this study was to conduct a histologic evaluation of irradiated calvarial defects in rats 4 weeks after applying fibroblast growth factor-2 (FGF-2) with hyaluronan or biphasic calcium phosphate (BCP) block in the presence or absence of adjunctive hyperbaric oxygen (HBO) therapy. METHODS: Twenty rats were divided into HBO and non-HBO (NHBO) groups, each of which was divided into FGF-2 and BCP-block subgroups according to the grafted material. Localized radiation with a single 12-Gy dose was applied to the calvaria of rats to simulate radiotherapy. Four weeks after applying this radiation, 2 symmetrical circular defects with a diameter of 6 mm were created in the parietal bones of each animal. The right-side defect was filled with the materials mentioned above and the left-side defect was not filled (as a control). All defects were covered with a resorbable barrier membrane. During 4 weeks of healing, 1 hour of HBO therapy was applied to the rats in the HBO groups 5 times a week. The rats were then killed, and the calvarial specimens were harvested for radiographic and histologic analyses. RESULTS: New bone formation was greatest in the FGF-2 subgroup, and improvement was not found in the BCP subgroup. HBO seemed to have a minimal effect on new bone formation. There was tendency for more angiogenesis in the HBO groups than the NHBO groups, but the group with HBO and FGF-2 did not show significantly better outcomes than the HBO-only group or the NHBO group with FGF-2. CONCLUSIONS: HBO exerted beneficial effects on angiogenesis in calvarial defects of irradiated rats over a 4-week healing period, but it appeared to have minimal effects on bone regeneration. FGF-2 seemed to enhance new bone formation and angiogenesis, but its efficacy appeared to be reduced when HBO was applied.

Improvement of the osteogenic potential of ErhBMP-2-/EGCG-coated biphasic calcium phosphate bone substitute: in vitro and in vivo activity

PURPOSE: The aim of this study was to evaluate the enhancement of osteogenic potential of biphasic calcium phosphate (BCP) bone substitute coated with Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2) and epigallocatechin-3-gallate (EGCG). METHODS: The cell viability, differentiation, and mineralization of osteoblasts was tested with ErhBMP-2-/EGCG solution. Coated BCP surfaces were also investigated. Standardized, 6-mm diameter defects were created bilaterally on the maxillary sinus of 10 male New Zealand white rabbits. After removal of the bony windows and elevation of sinus membranes, ErhBMP-2-/EGCG-coated BCP was applied on one defect in the test group. BCP was applied on the other defect to form the control group. The animals were sacrificed at 4 or 8 weeks after surgery. Histologic and histometric analyses of the augmented graft and surrounding tissue were performed. RESULTS: The 4-week and 8-week test groups showed more new bone (%) than the corresponding control groups (P<0.05). The 8-week test group showed more new bone (%) than the 4-week test group (P<0.05). CONCLUSIONS: ErhBMP-2-/EGCG-coated BCP was effective as a bone graft material, showing enhanced osteogenic potential and minimal side effects in a rabbit sinus augmentation model.

Bone remodeling function of orthodontic tooth movement in beagle dogs with periodontal defect regeneration under action of biphasic calcium phosphate / 吉林大学学报(医学版)

Objective: To observe the orthodontic tooth movement after regeneration of Beagl dog' s periodontal tissue defect with biphasic calcium phosphate (BCP), and to elucidate the mechanism of BCP as a scaffold material for periodontal regeneration. Methods: Six adult male Beagle dogs were selected; the right upper quardrant (B) and the left lower quardrant (D) regions of each dog were used as blank control group, and the left upper quardrant (A) and the right lower quardrant (D) regions were used to establish the dog models of periodontal tissue defect of bilateral incisors. BCP was implanted into the defect to regenerate the defect. After 12 weeks of BCP implantation into the defect for defect tissue regeneration, the orthodontic tooth movement models were established (experimental group). Stress stimulation was applied in experimental group and control group, respectively. Two Beagle dogs were randomly executed at 1, 2 and 4 weeks after loading. The specimens were stained, the histological changes of regenerated periodontal tissue and the expression of core binding factor al (Cbfal) regulating osteogenesis under stress were observed; the changes in normal periodontal tissue under the same stress were observed. Results: The Masson staining results showed that the periodontal ligament of the dogs in experimental group and control group became narrower and denser at 1 week after stress stimulation; the alveolar bone of the dogs in dogs in experimental group was mainly blue; the alveolar bone of the dogs in control group was generally red except for the compression area of the periodontal ligament. At 4 weeks after stress stimulation, the alveolar bone of the dogs in experimental group was red-blue, while the alveolar bone of the dogs in control group was red; the blood vessels in periodontal ligament of the dogs in two groups were rounded. One week after stress stimulation, the alveolar bone surface of the dogs in experimental group and control group was covered with bone resorption lacunae containing the multinucleated osteoclasts, the cytoplasmic Cbfal staining was positive, and the compressed and deformed periodontal ligament cells were arranged disorderly. Four weeks after stress stimulation, the osteoclasts disappeared in experimental group, and the bone resorption lacunae was filled by osteoblasts, and the osteoblasts on the other side of the trabecula were also active; the expression of Cbfal was still found in the bone marrow mesenchymal cells and the marginal osteoblasts of alveolar bone. The expression of Cbfal was weak in control group. Conclusion: The periodontal tissue regenerated by BCP has reached the normal periodontal tissue. Under the action of orthodontic force, it has normal osteogenesis function and can complete the bone remodeling process of orthodontic tooth movement.

Preparation of polydopamine coated 3D printed biphasic calcium phosphate tissue engineering scaffold and its evaluation / 吉林大学学报(医学版)

Objective: To coat polydopamine (PDA) on the surface of biphasic calcium phosphate (BCP) scaffold prepared by 3D printing and construct a novel bone tissue engineering scaffold with high osteogenic activity, and to conduct a preliminary evaluation on its application potential.Methods:BCP bioceramic scaffolds were prepared by 3D printing technology, and then they were immersed in dopamine solution for a certain period to form a nanoscale PDA film structure on the surface.The PDA-free scaffolds were named 3DBCP group, and the PDA-coated scaffolds were named PDA-3DBCP group. Scanning electron microscope (SEM) was used to observe the surface topography of the scaffolds in each group; the hydrophilicity of the material was characterized by measuring the water contact angle of the scaffold surface; the scaffold porosity was determined by the specific gravity method, and the mechanical strength was tested by the universal testing machine; CCK-8 assay was adopted to detect the cell proliferation activity on the scaffold.Results:Compared with 3DBCP group, the surface water contact angle of the the scaffolds in PDA-3DBCP group was significantly reduced (t=5.06,P0.05;t=0.002,P>0.05).The cells were inoculated into the scaffolds and cultured for 1, 3 and 5 d;the CCK-8 assay results showed that the proliferation activities of the cells in two groups were gradually increased with the prolongation of the culture time. Furthermore, compared with 3DBCP group, the cell proliferation activity of the cells in PDA-3DBCP group on the 5th day was significantly increased (t=39.3,P<0.05).Conclusion: The PDA-coated 3D printed BCP porous scaffold has the advantages in characterization,it can improve the cell proliferation ability, which shows the potential as bone tissue engineering scaffolds.

Eight-week healing of grafted calvarial bone defects with hyperbaric oxygen therapy in rats

PURPOSE: The purpose of this study was to evaluate the synergistic effect of adjunctive hyperbaric oxygen (HBO) therapy on new bone formation and angiogenesis after 8 weeks of healing. METHODS: Sprague-Dawley rats (n=28) were split into 2 groups according to the application of adjunctive HBO therapy: a group that received HBO therapy (HBO group [n=14]) and another group that did not receive HBO therapy (NHBO group [n=14]). Each group was divided into 2 subgroups according to the type of bone graft material: a biphasic calcium phosphate (BCP) subgroup and an Escherichia coli-derived recombinant human bone morphogenetic protein-2-/epigallocatechin-3-gallate-coated BCP (mBCP) subgroup. Two identical circular defects with a 6-mm diameter were made in the right and left parietal bones of each rat. One defect was grafted with bone graft material (BCP or mBCP). The other defect was not grafted. The HBO group received 2 weeks of adjunctive HBO therapy (1 hour, 5 times a week). The rats were euthanized 8 weeks after surgery. The specimens were prepared for histologic analysis. RESULTS: New bone (%) was higher in the NHBO-mBCP group than in the NHBO-BCP and control groups (P<0.05). Blood vessel count (%) and vascular endothelial growth factor staining (%) were higher in the HBO-mBCP group than in the NHBO-mBCP group (P<0.05). CONCLUSIONS: HBO therapy did not have a positive influence on bone formation irrespective of the type of bone graft material applied after 8 weeks of healing. HBO therapy had a positive effect on angiogenic activity.