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1.
Article in Chinese | MEDLINE | ID: mdl-36878498

ABSTRACT

Objective: To identify the internal nasal valve (INV) and to evaluate its key parameters in the established 3D models of nasal cavity space via Mimics from CT images, in order to provide evidence for quantitative diagnosis of nasal valve compromise. Methods: A total of 32 Han adults without nasal diseases who underwent maxillofacial CT test in Shanghai Ninth People's Hospital from January 2015 to December 2018 were retrospectively recruited, including 16 males and 16 females, with the age ranged from 20 to 80 years (50% age<50 years old). Maxillofacial CT images were used to create 3D model of nasal cavity space. The INV was identified and the following parameters were measured: the angle between the INV and the nasal bone (θINV-B), unilateral cross-sectional area of the INV (AINV-R, AINV-L), total cross-sectional area of the INV (AINV), unilateral height of the INV (HINV-R, HINV-L), unilateral nasal valve angle (αINV-R, αINV-L), and the sum of nasal valve angle (αINV). The AINV in our study was compared with the results of the previously adopted planes (PlaneC, perpendicular to the hard palate and PlaneB, plane perpendicular to the nasal bone). The parameters above were compared among genders, age and race groups. SPSS 26 and GraphPad Prism 9 software were used for statistical analysis and mapping of data. Results: The AINV in our study was (214.87±52.94) mm², which was significantly less than that of PlaneC (254.97±47.80) mm² and PlaneB (226.07±57.36) mm². The measured parameters were as follows: θINV-B was (82.07±7.06)°; AINV-R was (112.66±31.39) mm²; AINV-L was (102.21±27.14) mm²; AINV was (214.87±52.94) mm²; HINV-R was (24.87±4.62) mm; HINV-L was (24.35±4.86) mm; αINV-R was (20.48±2.99)°; αINV-L was (19.65±3.82)°; αINV was (40.13±6.24)°. The AINV-R was larger than AINV-L (t=2.33, P<0.05); The HINV, AINV-R, AINV-L and AINV of males were more than those of females (t value was 5.77, 3.21, 2.91 and 3.52, respectively, all P<0.01). The AINV of the young group (<50 years) was larger than that of the old group (t=2.83, P<0.01); The θINV-B was different between the Han people and the Caucasian (t=2.92,P<0.01). The αINV of the Han people was larger than that of Caucasians (Z=-6.92, P<0.01), but the HINV was smaller (Z=-3.89, P<0.01). Conclusion: The AINV carried out in 3D models of nasal cavity space is significantly smaller than that obtained by the previous methods of CT evaluation. INV static parameters differ among genders, age and race groups.


Subject(s)
Nasal Cavity , Nose , Adult , Female , Humans , Male , Young Adult , Middle Aged , Aged , Aged, 80 and over , Nasal Cavity/diagnostic imaging , Retrospective Studies , China , Nasal Bone
2.
Article in Chinese | MEDLINE | ID: mdl-36992647

ABSTRACT

Objective: Through the use of high-density polyethylene implants in adults with cleft lip and palate nasal deformities and abnormal functions, to evaluate the clinical effect of postoperative patients on improving nasal shape and symptoms. Methods: A retrospective study of 12 patients with nasal deformities after cleft lip and palate surgery in the Shanghai Ninth People's Hospital Affiliated to Shanghai JiaoTong University School of Medicine from January 2018 to January 2022 was completed, including 7 males and 5 females, with the age ranging from 18 to 29 years. All the patients underwent nasal deformity correction, and nasal septum correction was performed if necessary. High-density polyethylene implants (MEDPOR/Su-Por) were used intraoperatively. Follow-up for at least 6 months was performed to measure the relevant appearance indicators and subjective Visual Analog Scale (VAS) scores, and to compare the clinical effects before and after surgery. SPSS 22.0 software was used for statistical analysis. Results: Before and after surgery, the average VAS score of nasal obstruction decreased by (4.83±0.94) points; the average VAS score of appearance satisfaction increased by (3.92±1.08) points; the height of nasal columella was increased by (1.79±0.78)mm; the height of nasal tip was increased by (2.79±1.50)mm; the height of ipsilateral nostril was increased by (1.83±0.62)mm; the width of the ipsilateral nasal floor was reduced by (0.42±0.47)mm. All of above were statistically significant (all P<0.05). Conclusion: High-density polyethylene implants can effectively improve the shape and function of the nose in operations related to cleft lip and palate nasal deformity and abnormal functions, and are an ideal synthetic material.

3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 43(12): 1881-1886, 2022 Dec 10.
Article in Chinese | MEDLINE | ID: mdl-36572458

ABSTRACT

Objective: To analyze the epidemiological characteristics and transmission chain of an epidemic of COVID-19 in Haidian district, Beijing. Methods: Descriptive epidemiological method was used to analyze the epidemiological characteristics of the epidemic, and field investigation and big data technology were used to analyze the transmission chain of the epidemic. Results: From April 27 to May 13, 2022, an epidemic of COVID-19 occurred in Haidian district. The strains isolated from the cases were identified by whole genome sequencing as Omicron variant (BA.2.2 evolutionary branch). A total of 38 infection cases were detected, including 34 confirmed cases and 4 asymptomatic cases. Most cases were mild ones (88.2%), no severe, critical or death cases occurred. The early clinical symptoms were mainly sore throat (50.0%) and cough (29.4%). The epidemic lasted for 17 days, resulting in 7 generations of the cases and involving 3 community transmissions, 2 working place transmissions and 8 family transmissions; the main infection routes were co-residence (47.6%) and co-space exposure (31.6%). The intergenerational interval M(Q1, Q3)was 3 (1, 6) days. The overall secondary attack rate was 1.5% (37/2 482), and the family secondary attack rate was 36.7% (18/49). Conclusions: The cases in this COVID-19 epidemic caused by Omicron variant had mild clinical symptoms, but the case clustering in families and communities was obvious, the transmission was rapid, and the risk for co-space exposure was high. It is necessary to use information technology to identify close contacts in the local population for the rapid and effective blocking of the epidemic spread.


Subject(s)
COVID-19 , Epidemics , Humans , COVID-19/epidemiology , Beijing/epidemiology , SARS-CoV-2
4.
Zhonghua Yi Xue Za Zhi ; 102(19): 1472-1475, 2022 May 24.
Article in Chinese | MEDLINE | ID: mdl-35599414

ABSTRACT

This study aims to explore the clinical efficacy of arthroscopic-assisted reduction combined with robot-navigated nail placement in the treatment of talar neck fractures. The clinical data of 13 patients with talar neck fracture in Xuzhou Benevolent Hospital from January 2018 to January 2021 were analyzed in the retrospective study. Among them, there were 9 males and 4 females, aged (36±12) years; there were 8 cases suffered on the right and 5 cases on the left. All patients were reset under arthroscopy and cannulated screws were placed in combination with three-dimensional navigation and positioning of orthopedic robot. The wounds and complications were observed in the postoperative follow-up. The activities of bilateral ankle dorsiflexion and plantar flexion were measured in the last follow-up. The visual analogue scale score (VAS) of pain in the affected feet before operation were compared with that at the last follow-up. The ankle and hind foot work energy scale of American Foot and Ankle Association (AOFAS) was used to assess the ankle function. The results showed that the wounds of 13 patients healed in one stage. The operation time was (95±45) min and the blood lose was (45±10) ml. All the patients were followed-up for (15.0±3.5) months. Two cases developed subtalar arthritis without talus necrosis and fracture nonunion. At the last follow-up, there was no significant difference in the dorsal extension and plantar flexion of the ankle between the affected side and the healthy side (25.8°±1.9° vs 26.2°±2.3°, 44.2°±2.7° vs 44.7°±2.8°, both P>0.05). The VAS score of pain in the affected foot at the last follow-up was 0.53±0.18, it was significantly lower than that before operation (0.87±0.29) (P<0.001). The mean AOFAS ankle and hind foot energy scale of the ankle function was 93.5 at the last follow-up. It's showed that treatment of talus neck fracture with arthroscopy assisted and robot guided nail placement is satisfactory and is worthy of clinical promotion.


Subject(s)
Ankle Fractures , Robotics , Talus , Ankle Fractures/surgery , Female , Fracture Fixation, Internal , Humans , Male , Pain , Retrospective Studies , Talus/surgery , Treatment Outcome
6.
Article in Chinese | MEDLINE | ID: mdl-33832190

ABSTRACT

Objective: To investigate the clinical effects of single-stage auricular reconstruction and hearing rehabilitation in children with microtia and external auditory canal atresia. Methods: Sixty eight cases of microtia with external auditory canal atresia (53 males and 15 females, age from 7 to 12 years, with a median age of 8.8 years), who received operations in Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine from July 2017 to December 2019 were collected.A total of 28 cases received auricle reconstruction with high-density polyethylene (Medpor) framework and hearing reconstructions, among which 20 patients received the traditional external auditory canal and middle ear repair (EACR), and eight patients were implanted bone conduction device bone bridge(BB) simultaneously.In the control group, 40 patients only received Medpor frame implantation for auricle plasty. Postoperative changes in auricle morphology and auditory function and postoperative complications were evaluated. Results: After three to thirty months follow-ups, the auricles shape recovered well in all three groups. The average scores of 14 fine structures in the auricles were 9.43(EACR) and 10.67(BB) points. The average score of auricle symmetry were 6.83(EACR) and 6.00(BB) points. There was no significant difference compared to the auricle reconstruction group (8.23/6.20 points). P>0.05. After surgery, the average hearing improvement in the BB group was 43.33 dB HL and the average speech recognition threshold declined 42.28 dB HL. In the EACR group, the average hearing improvement was 4.13 dB HL and the average speech recognition threshold declined 11.36 dB HL. No vertigo, tinnitus, cerebrospinal fluid leakage and other complications occurred in all the patients. In the EACR group, sensorial hearing loss, auricle stent fracture, ear canal restenosis and ear canal atresia occurred in one patient respectively. In the auricle group, one auricle stent exposure and one facial branch nerve injury occurred. Nearly ten patients had difficulty in hair growth at scalp incisions. Conclusions: The operation of single-stage auricular reconstruction and hearing rehabilitation for microtia is feasible. The methods of hearing reconstruction should be determined by evaluating the development of the inner and middle ear of the patients. For those with poor mastoid development, bone bridge implantation is recommended to achieve a stable and significant hearing effect.


Subject(s)
Congenital Microtia , Hearing Loss , Plastic Surgery Procedures , Child , China , Congenital Microtia/surgery , Female , Hearing , Hearing Loss/rehabilitation , Humans , Male , Polyethylenes
7.
Fa Yi Xue Za Zhi ; 37(1): 49-53, 2021 Feb.
Article in English, Chinese | MEDLINE | ID: mdl-33780184

ABSTRACT

ABSTRACT: Objective To explore the causes and characteristics of medical disputes caused by death after cardiac surgery and to analyze the pathological changes after cardiac surgery and the key points of forensic anatomy, thus to provide pathological evidence for clinical diagnosis and treatment of cardiac surgery and judicial appraisal as well as reference for the prevention of medical disputes in such cases. Methods Forensic pathological cases of medical disputes caused by death after cardiac surgery which were accepted by the Center for Medicolegal Expertise of Sun Yat-Sen University from 2013 to 2018 were analyzed retrospectively from aspects such as causes of death, pathological diagnosis, surgery condition, medical misconduct, and so on. Results The causes of death after cardiac surgery of 43 patients were abnormal operation, low cardiac output syndrome, postoperative infection, postoperative thrombosis, and other diseases. Among the 43 cases, there were 18 cases without medical fault while 25 cases had medical fault. Conclusion The medical disputes caused by death after cardiac surgery are closely related to the operative technique and postoperative complications. The causes of medical faults include defects in diagnosis and treatment technique, as well as unfulfillment of duty of care.


Subject(s)
Cardiac Surgical Procedures , Dissent and Disputes , Cardiac Surgical Procedures/adverse effects , Forensic Medicine , Forensic Pathology , Humans , Retrospective Studies
9.
Zhonghua Shao Shang Za Zhi ; 35(8): 604-607, 2019 Aug 20.
Article in Chinese | MEDLINE | ID: mdl-31474041

ABSTRACT

Objective: To summarize the effects of medial upper arm bilobed free flaps in the repair of two skin and soft tissue defects of hand. Methods: From May 2014 to May 2016, 7 patients of two skin and soft tissue defects of hand with exposures of phalanges and tendons were treated in Xuzhou Renci Hospital, including 5 males and 2 females, aged from 19 to 41 years. Each defect area ranged from 3.0 cm×1.5 cm to 6.0 cm×3.0 cm. The medial upper arm bilobed free flaps were used to repair the defects, and the area of each lobe of the flaps ranged from 4.0 cm×2.0 cm to 8.0 cm×3.5 cm. The donor sites were sutured directly. The survival of the flaps was recorded. During follow-up, the recovery of donor and recipient sites was observed, the two-point discrimination distance of the flaps was measured, and the hand function was assessed by the trial criteria of the upper limb functional assessment of the Hand Surgery Society of the Chinese Medical Association. Results: All flaps survived smoothly, and the wounds and donor site incisions were healed. All patients were followed up, and the follow-up time lasted for 6 to 15 months. The color and texture of the flaps were similar to the surrounding normal skin, and the shape of the flaps was good. There was no obvious scar in the donor site, and the elbow joint function was normal. One patient developed ulnar numbness one month after operation and relieved after 3 months of treatment with neurotrophic drugs and local physiotherapy, etc. Six months after operation, the two-point discrimination distance of the flaps was 5.5-8.0 mm, and the hand function evaluation was excellent in 3 cases, good in 3 cases, and middle in 1 case. Conclusions: The medial upper arm bilobed free flap has both good texture and good appearance, and the scar of donor site is concealed. It is a good method to repair two skin and soft tissue defects of hand.


Subject(s)
Free Tissue Flaps/transplantation , Hand/surgery , Plastic Surgery Procedures , Soft Tissue Injuries/surgery , Adult , Arm , Female , Humans , Male , Skin Transplantation , Wound Healing , Young Adult
10.
Genet Mol Res ; 13(1): 1955-63, 2014 Mar 17.
Article in English | MEDLINE | ID: mdl-24668683

ABSTRACT

Laryngeal carcinoma is a common tumor of the head and neck region. This study aimed to examine the outcomes of laryngectomy in elderly patients with laryngeal carcinoma. One-hundred twenty-two patients (male, 117; female, 5) aged 60 years or older (range, 60-94 years) who underwent laryngectomy between 1996 and 2010 were included. All patients were diagnosed with squamous cell carcinoma of the larynx, and 95 patients (77.9%) had additional concurrent diseases. Tumors were staged according to the TNM categories of the American Joint Committee on Cancer 2002 criteria; there were 16 stage-I, 24 stage-II, 52 stage-III, and 30 stage-IV cases. With regard to treatment modalities, 10 patients underwent transoral laser laryngectomy, 25 underwent partial laryngectomy, and 87 underwent total laryngectomy. When necessary, neck dissection was performed according to the Dalian criteria set in 2004 (a Chinese standard). Of the 122 cases, there were 114 cases of grade I (93.4%), 5 cases of grade II, and 3 cases of grade III (pharyngeal fistula in 2 cases recovered after 2 weeks of care) wound healing. No significant differences were observed in the occurrence or severity of comorbidities. The 1-, 3-, and 5-year actuarial survival rates were 97.5% (119/122), 84.4% (92/109), and 68.4% (67/98), respectively. Age alone should not be used to determine treatment options for elderly patients with squamous cell carcinoma. Presuming that careful pre-treatment evaluations are performed, laryngectomy is a key method for elderly patients with laryngeal carcinoma.


Subject(s)
Carcinoma, Squamous Cell/surgery , Laryngeal Neoplasms/surgery , Laryngectomy , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/pathology , Female , Humans , Laryngeal Neoplasms/epidemiology , Laryngeal Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Risk Factors , Survival Analysis , Treatment Outcome
11.
Insect Mol Biol ; 18(3): 365-71, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19523068

ABSTRACT

A cDNA encoding Pyridoxine 5'-phosphate oxidase (PNPO) from Bombyx mori was cloned and characterized (GenBank accession number: DQ452398). The cDNA encodes a polypeptide of 257 amino acid residues. The recombinant enzyme purified from Escherichia coli exhibited maximal activity at pH 9.0, and the K(m) values for the substrates of pyridoxine 5'-phosphate and pyridoxamine 5'-phosphate were determined as 0.65 and 1.15 micromol/l. It was found that B. mori PNPO shares 51.44% homology with humans, but several function-related, key amino acid residues in B. mori PNPO are different from the human and E. Coli gene. B. mori has a single copy of the PNPO gene, which spans a 3.5 kb region and contains five exons and four introns. B. mori PNPO is a homodimer, with each monomer containing nine antiparallel beta-strands and five alpha-helical segments. The secondary structure was deduced from computational study.


Subject(s)
Bombyx/enzymology , Pyridoxaminephosphate Oxidase/metabolism , Animals , Bombyx/genetics , Cattle , Escherichia coli/metabolism , Genome, Insect , Humans , Mice , Protein Structure, Tertiary , Pyridoxaminephosphate Oxidase/chemistry , Pyridoxaminephosphate Oxidase/genetics , Pyridoxaminephosphate Oxidase/isolation & purification , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Sequence Analysis, DNA , Sequence Homology, Amino Acid
12.
Clin Pharmacol Ther ; 83(2): 273-80, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17609683

ABSTRACT

The goal of this study was to determine the effects of genetic variation in the organic cation transporter 1, OCT1, on the pharmacokinetics of the antidiabetic drug, metformin. Twenty healthy volunteers with known OCT1 genotype agreed to participate in the study. Each subject received two oral doses of metformin followed by collection of blood and urine samples. OCT1 genotypes had a significant (P<0.05) effect on metformin pharmacokinetics, with a higher area under the plasma concentration-time curve (AUC), higher maximal plasma concentration (Cmax), and lower oral volume of distribution (V/F) in the individuals carrying a reduced function OCT1 allele (R61C, G401S, 420del, or G465R). The effect of OCT1 on metformin pharmacokinetics in mice was less than in humans possibly reflecting species differences in hepatic expression level of the transporter. Our studies suggest that OCT1 genotype is a determinant of metformin pharmacokinetics.


Subject(s)
Catecholamine Plasma Membrane Transport Proteins/genetics , Hypoglycemic Agents/pharmacokinetics , Metformin/pharmacokinetics , Octamer Transcription Factor-1/genetics , Polymorphism, Genetic , Administration, Oral , Adult , Animals , Area Under Curve , Blood Glucose/drug effects , Catecholamine Plasma Membrane Transport Proteins/metabolism , Female , Gene Frequency , Genotype , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/blood , Hypoglycemic Agents/urine , Male , Metformin/administration & dosage , Metformin/blood , Metformin/urine , Mice , Mice, Knockout , Octamer Transcription Factor-1/metabolism , Phenotype , Reference Values , Species Specificity
13.
Thromb Haemost ; 83(3): 455-61, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10744153

ABSTRACT

Tissue factor (TF) is a transmembrane glycoprotein that serves as an essential cofactor for plasma coagulation factor VII. TF procoagulant activity exhibits varying species specificity. In particular, guinea pig (GP) TF is unable to activate clotting in heterologous plasma systems, but the molecular basis for this phenomenon is not yet understood. The full-length GP TF cDNA was cloned and sequenced. The open reading frame encoded a predicted precursor protein of 289 amino acids (aa) which was expressed in a reticulocyte lysate system as a protein of apparent molecular weight of 34 kD. The identity of the predicted aa sequence of mature GP TF with rabbit, human, bovine, rat and mouse TF was 66.4, 64.4, 60.6, 53.2 and 52.2%, respectively. With a focus on sites of potential functional significance, we compared sequences within the known binding regions. The eleven residues at the interface region between the TF1 and TF2 modules, which bind to the EGF domain of VIIa, were perfectly conserved among the six species, with the exception of an isoleucine replacing a lysine in the guinea pig sequence. However, only four of the eleven binding residues in the TF1 module, known to interact with the catalytic domain of factor VII, and three of the five residues in the TF2 module, involved in binding the factor VII Gla domain, were conserved among species. We hypothesize that divergence at these regions contributes to the specificity and non-reciprocity of TF procoagulant activity between species.


Subject(s)
DNA, Complementary/genetics , Thromboplastin/genetics , Amino Acid Sequence , Animals , Base Sequence , Binding Sites/genetics , Cattle , Cloning, Molecular , Conserved Sequence , DNA Primers/genetics , Guinea Pigs , Humans , Mice , Molecular Sequence Data , Polymerase Chain Reaction , Rabbits , Rats , Sequence Homology, Amino Acid , Species Specificity , Thromboplastin/chemistry , Thromboplastin/metabolism
14.
Microb Pathog ; 28(3): 127-33, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10702354

ABSTRACT

Intracellular infection of endothelial cells with Rickettsia rickettsii results in increased steady-state levels of plasminogen activator inhibitor-1 (PAI-1) mRNA. Control mechanisms governing such increased expression in response to this novel stimulus have not been defined. In this study, we compared the stability of PAI-1 mRNA in infected and uninfected endothelial cells (EC) and explored the requirement for de novo host cell protein synthesis in the infection-induced increase of steady-state levels. The half-life of PAI-1 mRNA, which is constitutively expressed in cultured EC, increased from 18 h in uninfected EC to greater than 30 h in EC infected for 24 h, a time point at which increases in steady-state PAI-1 mRNA levels are noted. There was no change in stability of gamma-actin due to infection. Nuclear run-on studies revealed no apparent increase in transcription rate at 4, 18 and 24 h. R. rickettsii -induced increase in PAI-1 mRNA was blocked by the eukaryotic protein synthesis inhibitor, cycloheximide, which suggests that this response requires de novo host cell protein synthesis. These results provide evidence that post-transcriptional control mechanisms are operative in the regulation of PAI-1 during R. rickettsii infection.


Subject(s)
Endothelium, Vascular/metabolism , Plasminogen Activator Inhibitor 1/metabolism , Rickettsia rickettsii , Actins/metabolism , Blotting, Northern , Cells, Cultured , Cycloheximide/pharmacology , Endothelium, Vascular/microbiology , Gene Expression Regulation/drug effects , Humans , Plasminogen Activator Inhibitor 1/genetics , Protein Synthesis Inhibitors/pharmacology , RNA Processing, Post-Transcriptional/drug effects , RNA, Messenger/analysis , Rocky Mountain Spotted Fever/microbiology
16.
Infect Immun ; 66(3): 1070-5, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9488397

ABSTRACT

The vascular endothelial cell (EC) is a primary target of infection with Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever. Changes in gene transcription elicited by intracellular infection, including EC expression of the coagulation pathway initiator known as tissue factor (TF), may contribute to the vascular pathology observed during disease. Nuclear run-on analysis of uninfected and infected, cultured human endothelial cells revealed that the rate of TF mRNA transcription is enhanced more than twofold at 3 h following infection, thus coinciding with increased steady-state levels of TF mRNA. TF mRNA remained relatively unstable during infection, with a half-life of 1.6 h. The eukaryotic protein synthesis inhibitor cycloheximide did not block R. rickettsii-induced increase in TF mRNA levels and actually resulted in its superinduction, thus revealing that de novo synthesis of host cell protein was not prerequisite to this transcriptional response. Involvement of the transcription factor NF-kappaB in R. rickettsii-induced TF expression was demonstrated by using two unrelated inhibitors of NF-kappaB activation. The antioxidant pyrrolidinedithiocarbamate and the proteasome inhibitor N-tosyl-L-phenylalanine chloromethyl ketone blocked expression of TF mRNA and activity during infection. This study demonstrates that R. rickettsii infection results in transcriptional activation of the TF gene and that this response involves activation of the transcription factor NF-kappaB.


Subject(s)
Endothelium, Vascular/metabolism , Gene Expression Regulation , NF-kappa B/physiology , Rocky Mountain Spotted Fever/metabolism , Thromboplastin/biosynthesis , Cells, Cultured , Cycloheximide/pharmacology , Humans , Proline/analogs & derivatives , Proline/pharmacology , RNA, Messenger/analysis , Thiocarbamates/pharmacology , Thromboplastin/genetics , Tosylphenylalanyl Chloromethyl Ketone/pharmacology , Transcription, Genetic
17.
Thromb Haemost ; 75(4): 600-6, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8743186

ABSTRACT

Changes in PAI-1 expression in human umbilical vein endothelial cells (HUVEC) were studied following in vitro infection with Rickettsia rickettsii. A 1.8-fold increase in secreted PAI-1 activity occurred in infected versus control cultures (p = 0.03) at 24 h but not at earlier timepoints. A similar increase (1.4-fold) in secreted PAI-1 antigen (p < 0.005) was measured by ELISA. To determine whether this increase was due to increased synthesis of PAI-1, HUVEC were metabolically labeled with 35S-methionine concurrent with R. rickettsii infection. Such infection resulted in a 1.9-fold increase in labeled PAI-1 in the medium at 24 h (p = 0.036). Increase steady-state levels of PAI-1 mRNA were detected as early as 18 h by Northern blot analysis, peaking (5.5-fold) at approximately 24 h. These results indicate that PAI-1 production is increased in RR-infected endothelial cells, an effect that may contribute to the vascular occlusions noted in Rocky Mountain spotted fever.


Subject(s)
Endothelium, Vascular/metabolism , Plasminogen Activator Inhibitor 1/biosynthesis , Rocky Mountain Spotted Fever/metabolism , Cells, Cultured , Culture Media , Endothelium, Vascular/pathology , Enzyme-Linked Immunosorbent Assay , Humans , Rocky Mountain Spotted Fever/pathology
18.
Blood ; 83(6): 1527-34, 1994 Mar 15.
Article in English | MEDLINE | ID: mdl-8123842

ABSTRACT

Microvascular thrombi underlie many of the clinical manifestations of Rocky Mountain spotted fever (RMSF), a disease characterized by Rickettsia rickettsii infection of vascular endothelial cells. Studies were designed to determine whether R rickettsii-infection of cultured human umbilical vein endothelial cells results in tissue factor (TF) induction, a process that could directly activate coagulation in infected vessels. Whereas uninfected endothelial cell cultures showed essentially undetectable TF mRNA and activity, both TF mRNA and activity were present after R rickettsii infection. TF mRNA levels were transient, peaking at 4 hours after the initiation of infection, whereas the peak of TF activity occurred at 8 hours. Induction of the TF response requires the intracellular presence of R rickettsii organisms, because uninfected rickettsia were ineffective and the response was blocked by inhibiting rickettsial entry using cytochalasin B. TF induction was not mediated by endothelial cell release of soluble factor, because no response was induced using culture medium conditioned by R rickettsii-infected cells. Furthermore, preadsorption of suspensions of R rickettsii with polymyxin B to remove contaminating lipopolysaccharide did not eliminate the TF response. Induction of TF in vital endothelial cells during R rickettsii infection could be the trigger for vascular thrombus formation of RMSF.


Subject(s)
Endothelium, Vascular/metabolism , Endothelium, Vascular/microbiology , Rickettsia rickettsii/pathogenicity , Thromboplastin/biosynthesis , Cells, Cultured , Humans , Lipopolysaccharides/pharmacology , RNA, Messenger/analysis , Simplexvirus/pathogenicity , Thromboplastin/genetics , Thrombosis/etiology
19.
Blood ; 78(10): 2595-602, 1991 Nov 15.
Article in English | MEDLINE | ID: mdl-1824255

ABSTRACT

The clinical manifestations of Rocky Mountain spotted fever (RMSF) result from Rickettsia rickettsii (R rickettsii) infection of endothelial cells and are mediated by pathologic changes localized to the vessel, including in situ thrombosis and tissue ischemia. This study uses in vitro infection of cultured human umbilical vein endothelial cells with R rickettsii to test the hypothesis that such infection induces von Willebrand factor (vWF) release from Weibel-Palade bodies, a process that could contribute to thrombotic changes. At 24 hours postinfection, there was an increase in metabolically prelabeled large multimers of vWF in the culture medium, with a concomitant decrease of these forms in the cell lysate samples. This release reaction was specific for the large multimer pool of vWF, localized to Weibel-Palade bodies, because no change in the distribution of dimeric forms between cells and culture medium was detected. Double-label immunofluorescence staining showed an inverse correlation between the number of R rickettsii and the number of Weibel-Palade bodies in infected cells. Cell lysis was minimal at 24 hours postinfection, as no detectable intracellular precursor forms (molecular weight 260,000) of vWF were released into the culture medium, there was no decrease in cell viability as measured by trypan blue exclusion, and no increase in 51Cr-release into the culture medium was observed when compared with uninfected controls. Release was likely a direct effect of the intracellular presence of the organism, rather than due to a noxious soluble factor such as endotoxin, because culture medium conditioned by infected endothelial cells was ineffective at inducing release in uninfected endothelial cell cultures. In summary, in vitro infection of endothelial cells by R rickettsii induces release of Weibel-Palade body contents, a process that may contribute to the pathogenesis of RMSF.


Subject(s)
Endothelium, Vascular/physiology , Organelles/physiology , Rickettsia rickettsii/physiology , von Willebrand Factor/metabolism , Cell Survival , Cells, Cultured , Electrophoresis, Polyacrylamide Gel , Endothelium, Vascular/ultrastructure , Fluorescent Antibody Technique , Humans , Kinetics , Macromolecular Substances , Molecular Weight , Organelles/ultrastructure , Umbilical Veins , von Willebrand Factor/isolation & purification
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