Recurrent symptomatic aortic aneurysm in a young girl with tuberous sclerosis complex and review of the literature

An abdominal aortic aneurysm is a rare occurrence in pediatric populations. When present, it is usually associated with an underlying etiology such as a connective tissue disorder, inflammatory process, or noninflammatory medial degeneration. In the present report, we describe the case of a girl with tuberous sclerosis complex who underwent successful emergency open repair of a symptomatic infrarenal abdominal aortic aneurysm and recurrent type IV thoracoabdominal aortic aneurysm.

Hybrid repair of type II thoracoabdominal aortic aneurysm using modified branch-first technique

The hybrid modified branch-first technique has extended the feasibility of open thoracoabdominal aortic aneurysm (TAAA) repair in otherwise hostile aortic anatomy that is not entirely amenable for extent II open TAAA conventional repair or total endovascular repair. The modified branch-first open TAAA technique has been developed successfully at our center and has been used to treat extent III TAAAs with successful outcomes. By combining the modified technique with endovascular thoracic aortic repair, we have been able to successfully extend its use to more extensive extent II TAAAs. This could prove to be a useful technique in the armamentarium of aortic surgeons.

Alternative option for limb reperfusion cannula placement for percutaneous femoral veno-arterial ECMO

Veno-arterial extracorporeal membrane oxygenation (VA ECMO) is an established last line support for severe, acute cardiorespiratory failure. In the case of VA ECMO, peripheral cannulation via the femoral vessels is often advantageous when compared with the alternative central cannulation, and is associated with better clinical outcomes. One of the specific potential complications of peripheral femoral arterial cannulation for ECMO, however, is ipsilateral distal lower limb ischemia; a consideration especially when cannulating the vessel directly, as distal limb perfusion is invariably compromised by an occlusive effect of the arterial cannula within the femoral artery. The gold standard technique for lower limb reperfusion is a separate size 6-7 Fr cannula inserted proximally into the femoral artery, just below the insertion point of the ECMO return cannula, and connected directly to the ECMO circuit so that the blood flow is also directed distally to perfuse the entire limb. This functions well whether the ECMO cannula has been placed percutaneously or by surgical cut-down. Although proximal femoral arterial placement of the reperfusion cannula is the established and preferred technique, there are many technical challenges which may preclude its placement. Local haematoma or bleeding post ECMO insertion, peripheral vascular disease, constricted vasculature in severely shocked patients, or patient obesity are all common reasons why placement of the proximal reperfusion cannula may be difficult, or impossible. In such instances, our retrograde perfusion technique may maintain limb perfusion and may even be limb saving for patients on VA ECMO support.

The impact of protocol-based high-intensity pharmacological thromboprophylaxis on thrombotic events in critically ill COVID-19 patients

The reported incidence rate of venous and arterial thrombotic events in critically ill patients with COVID‐19 infections is high, ranging from 20% to 60%. We adopted a patient‐tailored thromboprophylaxis protocol based on clinical and laboratory presentations for these patients in our institution. We hypothesised that patients who received high‐intensity thromboprophylaxis treatment would experience fewer thrombotic events. The aims of our study were to explore the incidence of thrombotic events in this population; to assess independent factors associated with thrombotic events and to evaluate the incidence of haemorrhagic events. A retrospective review of all adult patients with confirmed SARS‐CoV‐2 infection admitted to the intensive care unit (ICU) between 1 March and 29 May 2020 was performed. The primary outcome was a composite of venous and arterial thrombotic events diagnosed during the ICU stay. Multivariable logistic regression was used to identify the independent factors associated with thrombotic events. A total of 188 patients met the inclusion criteria. All received some type of thromboprophylaxis treatment except for six patients who did not receive any prophylaxis. Of the 182 patients who received thromboprophylaxis, 75 (40%) received high‐intensity thromboprophylaxis and 24 (12.8%) were treated with therapeutic anticoagulation. Twenty‐one patients (11.2%) experienced 23 thrombotic events (incidence rate of 12.2% (95%CI 7.9–17.8)), including 12 deep venous thromboses, 9 pulmonary emboli and 2 peripheral arterial thromboses. The multivariable logistic regression analysis showed that only D‐dimer (OR 2.80, p = 0.002) and high‐intensity thromboprophylaxis regimen (OR 0.20, p = 0.01) were independently associated with thrombotic events. Thirty‐one patients (16.5%) experienced haemorrhagic events; among them, 13 were classified as major bleeding according to the International Society on Thrombosis and Haemostasis criteria. Therapeutic anticoagulation, but not the high‐intensity thromboprophylaxis regimen, was associated with major bleeding. A proactive approach to the management of thromboembolism in critically ill COVID‐19 patients utilising a high‐intensity thromboprophylaxis regimen in appropriately selected patients may result in lower thrombotic events without increasing the risk of bleeding.

Thromboelastography findings in critically ill COVID-19 patients

The rate of venous and arterial thrombotic events among patients infected with severe acute respiratory syndrome coronavirus-2 (SAR-CoV-2) is high. This may be due to a hypercoagulable state induced by the severe inflammation that results from the SAR-CoV-2 infection. We aimed to determine hypercoagulable states' incidence based on thromboelastography study and its association with thrombotic events in critically ill patients with coronavirus disease 2019 (COVID-19). Fifty-two COVID-19 patients who had thromboelastography study were retrospectively included. All patients received pharmacologic thromboprophylaxis. The hypercoagulable state was observed in 16 patients (30.8%). Among them, maximum amplitude and a-angle were elevated in 75% and 25%, respectively. Reaction time and K were low in only 12.5% for both of them. Inflammatory and coagulation markers, as well as thromboprophylaxis regimens, were not associated with a hypercoagulable state. Fourteen patients (27%) experienced a total of 16 thrombotic events, including 8 (57%) deep venous thrombosis, 6 (43%) pulmonary embolism, and 2 (14.3%) arterial thrombosis. The hypercoagulable state was not significantly associated with thrombotic events. In summary, we observed a lower rate of hypercoagulable state on thromboelastography study in critically ill COVID-19 patients. Also, the hypercoagulable state was not associated with the occurrence of thrombotic events.

Abdominal aortic aneurysm in the setting of Clostridium perfringens pancreatitis

We report a case of a 56-year-old woman who presented with worsening abdominal pain located in the left upper quadrant together with abdominal distention, nausea and anorexia. One month prior to this admission, she had presented and had been diagnosed with concurrent acute pancreatitis and rapidly expanding abdominal aortic aneurysm. The aneurysm was prioritised over the pancreatitis and she underwent uncomplicated endovascular repair. Cross-sectional imaging was consistent with infected pancreatic necrosis and also revealed a large collection located in the anterior pararenal space with extensive gas formation. An image-guided fluid aspiration revealed Clostridium perfringens as the causative organism. She was treated by placement of large bore drains along with irrigation and targeted intravenous antibiotic for 6 weeks. The collections resolved completely and at 6 months follow-up she was well and symptom free.

Median Arcuate Ligament Syndrome Is Not a Vascular Disease

BACKGROUND

Median arcuate ligament syndrome (MALS) is a rare disorder characterized by postprandial abdominal pain, weight loss, and celiac stenosis. Diagnosis can be challenging, leading to a delay in treatment. We report on our continued experience using a laparoscopic approach for this uncommon diagnosis.

METHODS

This is an Institutional Review Board-approved, prospectively collected retrospective analysis of patients treated with laparoscopic MAL release at our institution. Data collected included patient demographics, preoperative symptoms, operative approach, and postoperative outcomes. Patients were then contacted to complete a postoperative survey designed to assess the improvement of symptoms and overall patient satisfaction.

RESULTS

A total of 39 patients (33 women and 6 men) underwent laparoscopic MAL release from March 2007 to July 2014. Mean age was 40.6 years (range, 17-77 years). Thirty of 39 patients had a postoperative celiac axis ultrasound. Twenty-three had a patent celiac axis on postoperative duplex. Of the remaining 7, 5 with residual celiac axis stenosis and 1 with occlusion, reported complete resolution of their symptoms. One remaining patient with occlusion remained symptomatic. Thirty-three of 39 (84.6%) reported symptom relief after surgery. Nine of 33 (27.3%) responders had cardiovascular risk factors versus 4 of 6 (67%) nonresponders. Five patients with atypical presentations underwent preoperative diagnostic celiac plexus block using local anesthetic, with 4 reporting symptom reliefs after block. These 4 patients also reported postoperative symptom relief. One patient of 39 received a postoperative celiac stent placement and remained symptomatic. There were 4 conversions to open surgery (10.3%) and no deaths.

CONCLUSIONS

Laparoscopic MAL release continues to be a safe and effective means of managing MALS. Our data suggest that the symptoms associated with MALS are not related to vascular compromise, and atherosclerotic risk factors may predict poorer outcomes. Symptomatic relief is seen in the vast majority of patients undergoing this procedure. However, patient selection remains critically important in obtaining optimal results.

Postradiation Extraskeletal Osteosarcoma Masquerading as an Axillary Artery Pseudoaneurysm

BACKGROUND

A 68-year-old woman with a thoracoabdominal aortic aneurysm recently status after first-stage elephant trunk procedure with right brachiocephalic artery endarterectomy and reimplantation of the innominate and left carotid using a 14 × 10-mm branch graft presented to clinic with increasing pain in her right arm and shoulder for 2 weeks. She also had a remote history of radiation to the right axilla for breast cancer. On physical examination, she had a tender mass under her clavicle, numbness in shoulder and right hand weakness. Computed tomography scan revealed a 5.3 × 4.3-cm coarsely rim calcified lesion in the right axillary region reported as a pseudoaneurysm.

METHODS

She was taken to the operating room for exploration. After obtaining proximal and distal control, the mass revealed to be a solid tumor. The mass was removed, taking care to avoid the axillary artery and medial and lateral cords of the brachial plexus.

RESULTS

Pathology revealed an extraskeletal osteosarcoma.

CONCLUSIONS

Extraskeletal osteosarcoma is an extremely rare primary bone cancer, making up <1% of all osteosarcomas. Less than 350 cases are described in the literature. Of the cases described in the literature, less than 5% involve the upper extremity and/or thorax. They are aggressive tumors located in the soft tissue and not an extension of bone. Treatment involves multimodality therapy with surgical resection and adjuvant chemoradiation.

Comparison of eight published static finite element models of the intact lumbar spine: predictive power of models improves when combined together

Finite element (FE) model studies have made important contributions to our understanding of functional biomechanics of the lumbar spine. However, if a model is used to answer clinical and biomechanical questions over a certain population, their inherently large inter-subject variability has to be considered. Current FE model studies, however, generally account only for a single distinct spinal geometry with one set of material properties. This raises questions concerning their predictive power, their range of results and on their agreement with in vitro and in vivo values. Eight well-established FE models of the lumbar spine (L1-5) of different research centers around the globe were subjected to pure and combined loading modes and compared to in vitro and in vivo measurements for intervertebral rotations, disc pressures and facet joint forces. Under pure moment loading, the predicted L1-5 rotations of almost all models fell within the reported in vitro ranges, and their median values differed on average by only 2° for flexion-extension, 1° for lateral bending and 5° for axial rotation. Predicted median facet joint forces and disc pressures were also in good agreement with published median in vitro values. However, the ranges of predictions were larger and exceeded those reported in vitro, especially for the facet joint forces. For all combined loading modes, except for flexion, predicted median segmental intervertebral rotations and disc pressures were in good agreement with measured in vivo values. In light of high inter-subject variability, the generalization of results of a single model to a population remains a concern. This study demonstrated that the pooled median of individual model results, similar to a probabilistic approach, can be used as an improved predictive tool in order to estimate the response of the lumbar spine.

Effect of the intra-abdominal pressure and the center of segmental body mass on the lumbar spine mechanics - a computational parametric study

Determination of physiological loads in human lumbar spine is critical for understanding the mechanisms of lumbar diseases and for designing surgical treatments. Computational models have been used widely to estimate the physiological loads of the spine during simulated functional activities. However, various assumptions on physiological factors such as the intra-abdominal pressure (IAP), centers of mass (COMs) of the upper body and lumbar segments, and vertebral centers of rotation (CORs) have been made in modeling techniques. Systematic knowledge of how these assumptions will affect the predicted spinal biomechanics is important for improving the simulation accuracy. In this paper, we developed a 3D subject-specific numerical model of the lumbosacral spine including T12 and 90 muscles. The effects of the IAP magnitude and COMs locations on the COR of each motion segment and on the joint/muscle forces were investigated using a global convergence optimization procedure when the subject was in a weight bearing standing position. The data indicated that the line connecting the CORs showed a smaller curvature than the lordosis of the lumbar spine in standing posture when the IAP was 0 kPa and the COMs were 10 mm anterior to the geometric center of the T12 vertebra. Increasing the IAP from 0 kPa to 10 kPa shifted the location of CORs toward the posterior direction (from 1.4 ± 8.9 mm anterior to intervertebral disc (IVD) centers to 40.5 ± 3.1 mm posterior to the IVD centers) and reduced the average joint force (from 0.78 ± 0.11 Body weight (BW) to 0.31 ± 0.07 BW) and overall muscle force (from 349.3 ± 57.7 N to 221.5 ± 84.2 N). Anterior movement of the COMs from -30 mm to 70 mm relative to the geometric center of T12 vertebra caused an anterior shift of the CORs (from 25.1 ± 8.3 mm posterior to IVD centers to 7.8 ± 6.2 mm anterior to IVD centers) and increases of average joint forces (from 0.78 ± 0.1 BW to 0.93 ± 0.1 BW) and muscle force (from 348.9 ± 47.7 N to 452.9 ± 58.6 N). Therefore, it is important to consider the IAP and correct COMs in order to accurately simulate human spine biomechanics. The method and results of this study could be useful for designing prevention strategies of spinal injuries and recurrences, and for enhancing rehabilitation efficiency.

Application of finite element analysis in pre-operative planning for deformity correction of abnormal hip joints--a case series

In experimental and clinical research, it is difficult to directly measure responses in the human body, such as contact pressure and stress in a joint, but finite element analysis (FEA) enables the examination of in vivo responses by contact analysis. Hence, FEA is useful for pre-operative planning prior to orthopaedic surgeries, in order to gain insight into which surgical options will result in the best outcome. The present study develops a numerical simulation technique based on FEA to predict the surgical outcomes of osteotomy methods for the treatment of slipped capital femoral epiphyses. The correlation of biomechanical parameters including contact pressure and stress, for moderate and severe cases, is investigated. For severe slips, a base-of-neck osteotomy is thought to be the most reliable and effective surgical treatment, while any osteotomy may produce dramatic improvement for moderate slips. This technology of pre-operative planning using FEA can provide information regarding biomechanical parameters that might facilitate the selection of optimal osteotomy methods and corresponding surgical options.

The complete genome sequence of pepper severe mosaic virus and comparison with other potyviruses

The complete nucleotide sequence of pepper severe mosaic virus (PepSMV) was determined. The viral genome consisted of 9890 nucleotides, excluding a poly (A) tract at the 3' end of the genome. The PepSMV RNA genome encoded a single polyprotein of 3085 amino acid residues, resulting in ten functionally distinct potyviral proteins. The lengths of the 5' nontranslated region (NTR) and the 3' NTR were 164 and 468 nucleotides, respectively. The genome organization of the virus was typical for members of the genus Potyvirus in the family Potyviridae. The coat protein amino acid sequence identity between PepSMV and the other 45 potyviruses ranged from 53.4 to 79.7%. Sequence alignments and phylogenetic analyses of the potyviral polyprotein sequences revealed that PepSMV was the closest to potato virus Y (PVY) and closely related to members of the PVY subgroup. Our genome sequence data clearly confirmed that PepSMV belongs to a separate species in the genus Potyvirus.

Characterization and immunological analysis of ferritin from the hemolymph of Galleria mellonella

Ferritin, an iron-binding protein, was purified from the larval hemolymph of the wax moth, Galleria mellonella by KBr density ultracentrifugation and FPLC (Superose 6). The iron content of ferritin was determined by atomic emission spectroscopy and Ferene S stain. Native molecular mass of ferritin was estimated as 630 kDa. SDS-PAGE revealed that the ferritin consists of two major polypeptides of 26 and 32 kDa and one minor polypeptide of 30 kDa. An isoelectric point of ferritin was measured to be approximately 7.3 and only the 32-kDa subunit is glycosylated. The ferritin contains large amounts of lysine, glutamine, glutamic acid and leucine but tryptophan was not detected. Electron microscopic examination of negatively stained preparations showed an 11-nm particle in external diameter and 7-nm iron core. Ferritin is present in both the ovary and testis. Localization of ferritin by immunoelectron microscopy in ovary and testis revealed that the gold particles were located in vitelline membrane and yolk granules but not in follicular epithelium of ovary. In the testis, the gold particles were located in testicular fluid and lumen of vas deferens.

Zucchini green mottle mosaic virus is a new tobamovirus; comparison of its coat protein gene with that of kyuri green mottle mosaic virus

A novel virus we call zucchini green mottle mosaic virus (ZGMMV) was isolated from zucchini squash and its properties were determined. The size and shape of its virions, and other properties suggest that the virus is a tobamovirus. The coat protein (CP) genes of ZGMMV and kyuri green mottle mosaic virus (KGMMV), which also infects zucchini squash plants, were cloned and their nucleotides sequences were determined. The CP genes of ZGMMV and KGMMV are composed of 161 amino acid residues, and they share 77.6% amino acid identity. Western blot analysis showed that the two viruses are serologically related but not identical. Comparison of the sequences with those of sixteen other tobamoviruses revealed that the two viruses had much higher identity to cucumber green mottle mosaic virus (CGMMV), another tobamovirus infectious to cucurbit plants, than other tobamoviruses. The nucleotide and amino acid sequences of ZGMMV were from 29.5 to 78.4% and from 29.3 to 77.6% identical, respectively, to those of other tobamoviruses. The predicted virion assembly origins of the two tobamoviruses were located in the CP region of the genomic RNAs, and the predicted secondary structures were more similar to that of CGMMV than those of other tobamoviruses. The seventeen tobamo-viruses could be classified into three main subgroups based on the phylogenetic tree analysis on the CP gene, and ZGMMV and KGMMV formed a third subgroup together with CGMMV and sunn-hemp mosaic virus (SHMV). These results show that ZGMMV is a previously unknown member of the Tobamovirus genus.

Successful repair of myocardial free wall rupture after thrombolytic therapy for acute infarction

BACKGROUND

Controversy exists regarding the timing of thrombolytic administration and rupture rate.

METHODS

Hospital records at St. Luke's-Roosevelt Hospital of the 4 study patients were reviewed and compared with those of 41 patients from a group of 537 patients concurrently admitted with a diagnosis of myocardial infarction (MI).

RESULTS

Four patients experienced ventricular free wall rupture after having a MI between November 17, 1993, and July 28, 1995. All received tissue plasminogen activator. In 1 patient, pericardial effusion associated with a pseudoaneurysm was discovered in the operating room. The 3 others developed clinical pericardial tamponade before surgery. All 4 patients survived and left the hospital on postoperative days 10, 11, 11, and 82, respectively. During this same time period, 537 patients were admitted with MI, 41 of whom died; the study's 4 patients were compared with these 41.

CONCLUSIONS

These data demonstrate that rupture of the ventricular free wall can occur early after thrombolytic therapy and may have a subacute course. Prompt diagnosis and surgery offer excellent chances of surviving this fatal condition.

Chemical degradation of tobacco mosaic virus followed by infectivity assay, reverse transcription-polymerase chain reaction and gel electrophoresis

In order to determine the detection limit for chemically treated virions by gel electrophoresis, reverse transcription-polymerase chain reaction (RT-PCR) and infectivity assay, tobacco mosaic virus (TMV) exposed to various concentrations of chemicals was studied. When virions were exposed to 0.2 N HCl for 30 mins, partially degraded TMV particles were observed by gel electrophoresis. Under the same exposure, a major RT-PCR amplified DNA product corresponding to the target size of 806 bp, which decreased as a function of time, could be detected for up to 60 mins of exposure. When virions were treated with NaOH (0.02 N or higher normality) for 5 mins, partially degraded virions were detected by gel electrophoresis, exhibiting multiple band patterns. Exposure of the virions to 0.1 N NaOH for 5 mins revealed severely degraded viral RNA, but disappearance of the amplified RT-PCR products was apparent during 30-60 mins of exposure. Therefore, these data showed clearly the difference in the detection limit of gel electrophoresis and that of RT-PCR for the degraded viral RNA. In addition, the infectivity assay showed that the number of local lesions in Nicotiana rustica were significantly reduced by more than 95% when the virus was exposed to 0.2 N HCl for 15 mins or 0.1 N NaOH for 10 mins. From these results we conclude that loss of infectivity was not related to that of PCR product. Other chemical disinfectants such as phenol or formalin were also found to be effective to reduce the virus infectivity, but a corresponding degradation of viral RNA was detected by neither gel electrophoresis nor RT-PCR.

RT-PCR detection and identification of three species of cucumoviruses with a genus-specific single pair of primers

Reverse transcription and polymerase chain reaction (RT-PCR) was used for detection and identification of three cucumoviruses (cucumber mosaic virus, CMV; peanut stunt virus, PSV; tomato aspermy virus, TAV) in various plants sources with a single pair of primers, designed as CPTALL-3 and CPTALL-5. The pair of cucumovirus genus-specific primers that flank the coat protein gene were designed and used to amplify a DNA fragment of approximately ranging from 938 to 966 bp. The RT-PCR with the set of primers specifically amplified the target size of DNA fragment in all the tested cucumoviruses (CMV S-IA, S-IB and S-II, PSV and TAV). No DNA product of any length was produced when brome mosaic virus or tobacco mosaic virus RNA was used as templates. The cucumoviruses examined were differentiated by PCR-restriction fragment length polymorphism with different enzymes. This indicates that the designed primers are only specific for the cucumoviruses and useful for reliable information of identification of members of the Cucumovirus genus.

Gene silencing-mediated resistance in transgenic tobacco plants carrying potato virus Y coat protein gene

Unlike other pathogens, plant viruses are hardly controlled by chemical agents. Potato virus Y (PVY) is distributed around the world, and causes a great loss economically. In an attempt to minimize the damage by viruses, the PVY coat protein (CP) gene was introduced into tobacco by Agrobacterium-mediated transformation. A significant proportion of the transgenic plants displayed resistance to PVY and showed substantially decreased CP transgene expression at both protein and steady-state mRNA levels compared to susceptible transgenic or nontransgenic plants. A resistant plant was selected and self-fertilized for several generations until T4 progenitor lines were obtained. Most of these T4 plants accumulated extremely low levels of CP protein and steady-state mRNA, and exhibited almost complete resistance to PVY. DNA gel blot analysis revealed that the transgenic plants typically had two or three copies of the transgene. These results are characteristic of pathogen-derived resistance, in which the resistance against virus is the consequence of post-transcriptional gene silencing directed by homologous transgenes. To uncover factors that may play roles in gene silencing, sequences in the 3' part of the transcribed region of the CP gene were transcribed in vitro and the RNA fragments were incubated with cell extracts from transgenic plants. A ribonuclease activity was detected that appeared to be specific for this transcript in the PVY-resistant transgenic plants.

Regional distribution in the mouse of proteins homologous to artery-specific antigenic proteins (ASAPs)

We have reported the sequences of four novel proteins derived from extracts of human aortic tissue and a cDNA library from human aortic adventitia. These proteins are immunoreactive with serum immunoglobulins from patients with abdominal aortic aneurysms (AAA), and they have homologies of amino acid sequence with microfibrillar proteins of connective tissue. We are reporting separately that two of these proteins are artery-specific antigenic proteins (ASAPs) in man. The present work investigates the regional distribution of these two proteins (AAAP-40 and MatCAM-1) in mouse (E-beta-b). Antibodies were raised in rabbit against polypeptides encoding novel amino acid sequences, unique to these proteins (e.g., not reported in GenBank). Immunohistochemical studies with these two specific antibodies show conspicuous immunoreactivity of collagen-associated microfibrils in the aortic adventitia of the murine abdominal and thoracic aorta. Immunoreactive peptides were not present in brain, muscle, or kidney. These findings support the hypothesis that proteins occur in the mouse that are homologous to a unique family of aortic microfibrillar proteins in man.

Environmental measurements of total dust and fiber concentration in manufacturer and user of man-made mineral fibers

Man-made mineral fibers (MMMF), most of which are referred to as man-made vitreous fibers (MMVF), are mostly amorphous silicates manufactured from glass, rock, or other minerals. Analysis for MMMF have been restricted largely to the measurement of total airborne mass concentrations, but more recently to the determination of airborne fiber levels by phase contrast optical microscopy. In Korea, many small factories are related with manufacturing and using MMMF without any special evaluation of environmental measurements. Though MMMF are known as the substitute of asbestos and their toxicity are regarded as very low, MMMF do not totally excluded from the respiratory and/or skin diseases now. Therefore, we evaluated the environments of many workplaces with total dust and fiber concentration. Most dust and fiber concentrations were below threshold limit value (TLV) at various industries and working processes. However, these data showed a slight relationship between total dust and fiber concentration.

Nucleotide sequence analysis of the 3'-terminal region of two Korean isolates of lily symptomless Carlavirus and expression of the coat protein in E. coli

The 3'-terminal regions of the genomic RNAs of two Korean isolates of the lily symptomless Carlavirus (LSV), LSV-Ko and LSV-KII, were cloned and their nucleotide sequences were determined. The nucleotide sequence analysis and protein analysis by the Western blot revealed that E. coli expressed a 32-kDa protein that is the viral coat protein (CP) for the LSV. The two Korean strains share 98.4% and 98.3% sequence identities at the nucleotide and amino acid levels, respectively. The CP gene of LSV-Ko showed 99.1% and 87.0% nucleotide sequence identities, and 99.0% and 96.6% amino acid sequence identities with those of the Netherlands and the Japanese LSV strains, respectively. A pairwise amino acid sequence comparison revealed a sequence similarity of 29.6% to 69.8% between LSV-Ko and other species of the carlavirus. The 16 kDa protein of LSV-Ko shares 17.6% to 42.7% amino acid similarity with those of 8 other the carlaviruses, and they are variable in the N-terminal region. The Cys repeated zinc finger nucleic acid binding domain was found in the 16 kDa protein for all of the LSV strains. Sequence comparisons of the 7 kDa protein of LSV in the strain level showed significant identities from 100.0% to 98.4%. LSV-Ko shares 21.9% to 42.2% amino acid similarity with those of 8 other carlaviruses, 4 members of the potexviruses, and a closterovirus. LSV is closely related to blueberry scorch virus (BISV) based upon the phylogenetic tree analyses of the three proteins, indicating LSV to be a quite distinct member of the genus Carlavirus.

Sequence analysis of the coat protein and 3'-noncoding region for Korean and other strains of sweet potato feathery mottle virus

The 3'-terminal regions of the genomic RNAs of two Korean isolates of sweet potato feathery mottle potyvirus (SPFMV) were cloned and their nucleotide sequences of full-length coat protein (CP) gene and 3' noncoding region (NCR) were determined. The CP of the two Korean isolates contained 315 amino acid residues. The CP cistron sequences of the Korean isolates exhibit 72.7% to 98.7% nucleotide sequence identity and 79.9% to 99.0% amino acid identity when compared with those of 8 other known SPFMV strains. Pairwise comparison revealed sequence similarities of 47.4% to 62.1% at the nucleotide level, and 48.6% to 70.2% at the amino acid level between SPFMV and 21 other potyviruses. SPFMV CP has extensive amino acid sequence similarity to the other members of the genus Potyvirus throughout its central and C-terminal regions. The 3' NCR of the SPFMV showed 42.5% to 99.1% nucleotide sequence identities among the strains. The 3' NCR of SPFMV revealed 19.9% to 63.6% sequence similarities to those of 21 other potyviruses. These results support the assignment of SPFMV as a distinct member of the genus Potyvirus of the family Potyviridae.

Nucleotide sequence analysis of the coat protein genes of two Korean isolates of sweet potato feathery mottle potyvirus

The coat protein (CP) genes of the genomic RNA of two Korean isolates of sweet potato feathery mottle potyvirus (SPFMV), SPFMV-K1 and SPFMV-K2, were cloned and their complete nucleotide sequences were determined. Sequence comparisons of the two Korean isolates showed 97.8% amino acid identity in the CP cistron, and 79.9% to 99.0% identity with those of 6 other known SPFMV strains. Of 74 amino acid changes totally among the SPFMV strains, 39 changes were located at the N-terminal region. Pairwise amino acid sequence comparison revealed sequence similarities of 48.6 to 70.2% between SPFMV and 20 other potyviruses, indicating SPFMV to be a quite distinct species. Multiple alignment of the CP cistrons from other potyviruses showed that most of the conserved amino acid residues of the genus Potyvirus are well preserved in the corresponding locations.

Novel transglutaminase inhibitors reduce the cornified cell envelope formation

Transglutaminase (TGase) is a calcium-dependent enzyme which catalyzes the iso-peptide cross-link between peptide-bound glutamine and lysine in vivo. Though the cross-link is developed as a barrier function in the skin system, overexpression of this could invoke skin hyperkeratosis in psoriasis and roughness in aged skin. In former research, many strong irreversible TGase inhibitors failed application because of high cytotoxicity. We selected one peptide after primary screening of six synthetic peptides designed from domains of known TGase substrates. Then we attempted to reduce the size and finally obtained two tetrameric peptides. When we treated keratinocyte with these TGase inhibitors under calcium-induced differentiation, the formation of a cornified cell envelope (CE) was decreased to the same level of CE under proliferating conditions without cytotoxic effect. Therefore, we propose that these TGase inhibitors may be useful for solving the physiological hypercross-linking problems for pharmaceutical or cosmetic purposes.

Rapid detection and identification of odontoglossum ringspot virus by polymerase chain reaction amplification

The odontoglossum ringspot Tobamovirus (ORSV) movement and coat proteins genes were selected for the design of oligonucleotide primers for amplification of a 1,085 bp fragment. A combined assay of reverse transcription and the polymerase chain reaction (RT-PCR) was performed with 20-mer ORSV-specific primers and crude nucleic acid extracts from virus-infected orchids for rapid detection of the virus. The lowest concentration of template viral RNA required for detection was 10 fg. The RT-PCR is a 10(3) times more sensitive, reproducible and time-saving method than the enzyme-linked immunosorbent assay. No PCR product was observed when cymbidium mosaic potexvirus or a crude extract of healthy Cymbidium sp. were used as a template in RT-PCR with the same primers. The specificity of the primers was verified using other tobamoviruses RNAs.

The complete nucleotide sequence and genome organization of odontoglossum ringspot tobamovirus RNA

The complete nucleotide sequence of the genomic RNA of odontoglossum ringspot tobamovirus (ORSV) was determined. The RNA genome of ORSV is 6618 nucleotides long and contains five open reading frames (ORFs 1 to 5) coding for proteins of M(r) 126 K, 181 K, 34 K, 18 K and 52 K, respectively. This is the longest RNA of the known viruses of the Tobamovirus genus. The sequences of the ORSV RNA encoded proteins exhibit high homology to the proteins of the members of the Tobamovirus genus. The genomic organization and sequence analysis showed that ORSV is more closely related to tobacco mild green mosaic virus (TMGMV), pepper mild mottle virus (PMMV), tomato mosaic virus (ToMV) and TMV than to cucumber green mottle mosaic virus (CGMMV) and sunn-hemp mosaic virus (SHMV).

Cloning and sequencing of a cDNA encoding the coat protein of a Korean isolate of cymbidium mosaic virus

The 3'-terminal nucleotide (nt) sequence of the coat protein (CP)-encoding gene of the Korean isolate of cymbidium mosaic potexvirus (CyMV-K) has been determined. The sequence contained a full-length ORF coding for the viral CP. It comprises 663 nt and a polypeptide chain of 220 amino acids with a M(r) of 23,718. The stop codon (TGA) is followed by a 3'-untranslated region (3'-UTR) of 79 nt and a poly(A) tract. The putative polyadenylation signal, AATAAA motif, is found in the terminus of the 3'-UTR.

Cloning of the 3'-terminal region encoding movement and coat proteins of a Korean isolate of odontoglossum ringspot virus

The 3'-terminal 1855 nucleotides (nts) of a Korean isolate of odontoglossum ringspot tobamovirus (ORSV-Cy) were cloned and sequenced. The sequence contained two open reading frames, which encode the cell-to-cell movement protein (MP) and coat protein genes, and are 912 nts and 477 nts long, respectively. The MP gene contained a conserved sequence motif of tobamoviruses and putative assembly origin of the viral RNA locating between 1117 nts and 1292 nts from the 3'-end. The 3' untranslated region (UTR) of the virus comprises 414 nts, includes nine pseudoknots and a tRNA-like structure domain containing aminoacyl acceptor arm and the anticodon hairpin loop coding for histidine.

Systolic arterial pressure recovery after ventricular fibrillation in pigs

Ventricular fibrillation (VF) is induced during implantable cardioverter defibrillator insertion and can result in cardiovascular collapse. The relation between repeated VF trials of varying duration and systolic blood pressure (SBP) recovery rate was studied in 6 pigs. Two implantable cardioverter defibrillator patches were placed on the heart, and VF was varied in a cyclic pattern until cardiovascular collapse occurred. A negative logarithmic relation between SBP recovery rate and duration of VF was found in 4 of the pigs with correlation coefficients of 0.62 to 0.97 (p < 0.05). The overall correlation coefficient was 0.51 for all 116 data points (p < 0.001). Although there was a significant (p < 0.05) decrease in average (+/- standard error of the mean) baseline SBP in the second half of each experiment (83 +/- 5 mm Hg versus 77 +/- 6 mm Hg), no significant difference in SBP was observed during VF (17 +/- 1 mm Hg versus 16 +/- 1 mm Hg) or after 15 seconds of SBP recovery (51 +/- 4 mm Hg versus 46 +/- 3 mm Hg) between the two halves of the experiments. Cardiovascular collapse occurred without warning; epinephrine was effective in reversing it. In conclusion, SBP recovery rate and duration of VF have a negative logarithmic relation consistent with a negative effect on left ventricular contractility with prolongation of VF. The onset of cardiovascular collapse during implantable cardioverter defibrillator testing cannot be predicted on the basis of monitored blood pressure alone.

Nucleotide sequence analysis of a cDNA clone encoding the 34K movement protein gene of odontoglossum ringspot virus, ORSV-Cy, the Korean isolate

The partial nucleotide sequence of the 3'-terminal region of the Korean isolate of odontoglossum ringspot tobamovirus (ORSV-Cy) from cool-growing Cymbidium was determined. The sequence contained a full length open reading frame (ORF) coding for the viral cell-to-cell movement protein (MP). The ORF was located upstream of the coat protein gene and 105 nucleotides longer than that of tobacco mosaic virus (TMV). The ORF predicts a polypeptide chain of 303 amino acids with a molecular weight of 33573. The ORF contained a similar region of conserved sequence motif of tobamoviruses and putative assembly origin of the viral RNA was located at about 1,100 nucleotides away from the 3' end. The predicted amino acid sequence for the MP gene of ORSV-Cy is more closely related to pepper mild mottle virus (PMMV), TMV-vulgare and TMV-Rakkyo than to tobacco mild green mosaic virus (TMGMV), TMV-L, cowpea strain of TMV (SHMV), and cucumber green mottle mosaic virus (CGMMV).

Systolic arterial pressure recovery after ventricular fibrillation/flutter in humans

Although the elective induction of cardiac arrest for implantable defibrillator insertion under general anesthesia is widely used, the hemodynamics of recovery of arterial blood pressure after cardiac arrest is not well-defined. Accordingly, the time course of recovery of systolic arterial pressure was studied in seven patients during the repetitive induction of ventricular fibrillation (n = 6) or ventricular flutter (n = 1). The mean number of episodes of cardiac arrest was 7 +/- 2, and the mean drop in systolic pressure was 84 +/- 16 mmHg. The mean recovery time for systolic pressure was 10 +/- 6 seconds, the average systolic pressure recovery rate was 13 +/- 14 mmHg/sec, and the mean percent systolic pressure recovery was 94% +/- 9%. A negative logarithmic relation was found to exist between the rate of systolic arterial pressure recovery and the duration of ventricular fibrillation or flutter with a correlation coefficient of 0.68 to 0.97 (P < 0.05) in five of the seven patients. A linear relation between the time for systolic pressure recovery and duration of asystole was also defined. These results are consistent with the view that prolongation of ventricular fibrillation or flutter increases the duration of arterial pressure recovery through a negative effect on left ventricular contractility. Increased understanding of these relations may lead to increased safety of implantable defibrillator insertion.

Electrode-derived myocardial pH measurements reflect intracellular myocardial metabolism assessed by phosphorus 31-nuclear magnetic resonance spectroscopy during normothermic ischemia

To determine the ability of extracellular myocardial tissue pH measured with an intramural electrode to reflect myocardial intracellular metabolic status during normothermic ischemia, we studied 14 open-chest dogs with in vivo phosphorus 31-nuclear magnetic resonance spectroscopy during left anterior descending coronary artery occlusion (experimental group, group I, n = 7) or after a sham operation (control group, nonischemic, group II, n = 7). Phosphorus nuclear magnetic resonance spectra were acquired every 5 minutes at 4.7 tesla (256 averages, TR = 1000 msec, pulse width = 30 microseconds) with a 2 cm two-turn radiofrequency surface coil. Intracellular myocardial adenosine triphosphate peak area was normalized to an external phosphate standard. The change in adenosine triphosphate peak area was expressed as percent of baseline value. During 3 hours of normothermic ischemia the observed extracellular myocardial pH correlated with nuclear magnetic resonance-calculated myocardial pH in the ischemic dogs with an average r value of 0.94 (p less than 0.0001). During this same interval, the fall in extracellular myocardial pH correlated with the loss of adenosine triphosphate peak in each ischemic dog, with an average r value of 0.91 (p less than 0.0001). Thus extracellular myocardial pH, measured with an intramural electrode, correlated with nuclear magnetic resonance-derived myocardial pH and loss of myocyte adenosine triphosphate peak content and reflected the metabolic status of the myocyte during ischemia. These data validate the use of extracellular myocardial pH to assess the adequacy of myocardial preservation during aortic crossclamping for cardiac operations.

Spondylarthrography: the demonstration of spondylolysis by apophyseal joint arthrography

Twenty selected patients with spondylolysis have been studied following apophyseal joint arthrography. In each instance a communication with the defect of the pars interarticularis was demonstrated by the extension of contrast medium from injection into the adjacent facet joint. The clinical and radiological features are described. The anatomical basis of the abnormality is presented using macroscopic and radiographic correlation from a dissected cadaveric specimen of spondylolysis. Sixty-five per cent of the patients experienced significant relief of pain symptoms when long-acting local anaesthetic was introduced into the facet joint.

Acute traumatic intraosseous disc herniation

The clinical, radiologic, and discographic findings are reviewed in eight patients with acute traumatic intraosseous disc herniation. The syndrome should be considered in adolescent patients having severe back pain with limited radiation to the upper thigh, following significant compression/flexion stress to the spine. The intraosseous disc herniation can be confirmed by discography and reproduction of symptoms during the procedure is a helpful confirmatory feature. The radiologic natural history of the lesion is presented, and the role of bone scintigraphy is discussed. This type of injury may be responsible for considerable pain and disability in the adolescent age group and has proved extremely difficult to manage except by conservative treatment and analgesics.

Fracture of the cervical spine in ankylosing spondylitis

The radiological features, clinical findings and mortality rates of patients with ankylosing spondylitis complicated by cervical trauma have been reviewed. All patients had long-standing disease and half had sustained their fractures as a result of trivial accidents. There were 19 cervical fractures in 18 patients, which were chalkstick in type and occurred predominantly at the 6th and 7th cervical levels. Ten fractures passed through the upper part of the vertebral body, one through the mid-vertebral body and the final eight were through the disc space. The site of the fracture line was related to neurological outcome. Those patients whose fracture line ran through the disc space had significantly less neurological injury and a much better prognosis. Distraction at the fracture site had some relation to prognosis but horizontal displacement and angulation were not found to be of importance. This study confirms that cervical fracture with neurological complications may follow minor trauma in ankylosing spondylitis. The site of the fracture in relation to the vertebral bodies and discs appears to be of some prognostic relevance and careful radiological assessment of all patients with ankylosing spondylitis and cervical injury should be undertaken.

Observer variation in skeletal radiology

The factors that affect observer variation in bone radiology are analysed from data in the literature and on the basis of studies carried out at McMaster University on the hands and sacroiliac joints. A plea is made for presenting results in terms of Kappa statistics so that agreement due purely to chance is eliminated. In the conclusions the main variables that affect concordance are listed so that strategies can be developed to reduce observer variation. This is important in serial studies to ensure that the observer variations are smaller than the effect one wishes to measure.

The diagnostic value of bone scintigraphy in patients with low back pain

Bone scintigraphy has been studied in two groups of patients presenting with low back pain. In one group of 38 patients suffering "nonspecific" back pain, bone scintigraphy and laboratory findings were negative in 24. There were abnormal laboratory findings in all of the remaining 14 and 7 had positive bone scans indicative of clinically significant disease. Selection of patients for bone scintigraphy in this group should therefore be influenced by abnormal laboratory findings and elevation of the erythrocyte sedimentation rate in particular. By comparison, the bone scans were reviewed from another group of patients suffering previously known malignancy. Out of 138 patients, nearly 40% showed a positive bone scan due to subsequently proven metastasis. Bone scintigraphy was positive in a further 14% as a result of osteoporotic rib fracture and vertebral body collapse. In half of these, it was not possible to exclude malignancy by scintigraphy. The present findings indicate that bone scintigraphy is not a useful procedure in patients with long-standing low back pain who have normal radiographs and normal laboratory findings.

Gallium 67 scanning in rheumatoid arthritis

Gallium 67 scans were performed on both knees of 38 patients with rheumatoid arthritis. There was a significantly higher level of 67Ga accumulation in those knees with clinically active synovitis (p less than 0.001). Synovial white cell concentration was also elevated in the group with active synovitis. The white cell concentration correlated with the 67Ga knee/femoral ratio at the p less than 0.001 level. 67Ga activity in the synovial fluid was predominantly in the supinate and activity was also present in the synovium. The findings indicate that 67Ga uptake occurs in rheumatoid joints and reflects the degree of synovial inflammation.

Severe kyphosis due to congenital dorsal hemivertebra

Kyphotic deformity arising from failure of the formation of a vertebral body is described in nine patients. The study of the natural history demonstrates the progressive nature of this disorder resulting in severe deformity and neurological embarrassment. Early radiological recognition of this congenital deformity is essential and tomography is important in the early assessment. Tomography combined with myelography is essential to delineate the extent of bony abnormality and cord compression in severe kyphosis in order that adequate decompression and reconstructive surgery can be performed.

Apophyseal injection of local anesthetic as a diagnostic aid in primary low-back pain syndromes

Twenty-five out of 41 adult patients suffering from their first attack of acute low-back pain were subjected to local anesthetic injection into the maximally tender lumbar apophyseal joints under controlled conditions. Two clinical syndromes can be identified according to whether the patients responded to the facet injection or not. Various clinical differences were statistically significant and included a wider than normal spinal canal in the responding group. The clinical significance of these two distinct groups is discussed in detail.

Diaphyseal osteosarcoma

Fifteen cases of diaphyseal osteosarcomas were found in a review of 157 cases of long bone osteosarcoma (9.5%) and two further examples were added. The clinical and histological features of the diaphyseal osteosarcomas were indistinguishable from those of the commoner juxta metaphyseal osteosarcomas. The radiological features, however, fell into four distinct patterns: Group I had the classical appearance of a conventional osteosarcoma; Group II showed dense cortical sclerosis with bony expansion but no soft tissue swelling or break of the cortex at presentation; Group III presented with a pathological fracture through a purely osteolytic lesion; Group IV usually had the classical appearances of an osteosarcoma in the diaphysis but had, in addition, dense separate sclerotic lesions which were proximal to the tumour in the humerus and distal to it in the femur. The importance of these four groups lies in the quite distinct differential diagnosis which each presents.

Gallium-67 scanning in the painful total hip replacement

Pain following total hip replacement is a significant clinical and diagnostic problem. Technetium scanning has proved a sensitive indicator of infection or loosening but does not differentiate between them. This study assessed the value of gallium-67 to aid this differentiation. Thirty patients underwent revision surgery. Fourteen were proven to be infected and 13 had positive gallium scans as also did two patients without infection. The implications of these false interpretations are discussed. Increased gallium activity was correlated with the patterns of the 99mTc scans and arthrographic appearances. It is concluded that gallium-67 scanning is a valuable adjunct to the assessment of the painful hip replacement when infection is suspected.

Alterations in vertebral growth following prolonged plaster immobilisation

Long-term immobilisation in serial plasters for scoliosis, including the period of the adolescent growth spurt, leads to an increase in height of the vertebral bodies and a decrease of their height to width ratio. These changes are at the expense of the disc which is reduced in thickness. This stimulating effect on the vertebral body growth is probably due to the changes in mechanical factors.

The detection of spinal pseudarthrosis in ankylosing spondylitis

Spinal pseudarthrosis in ankylosing spondylitis can be difficult to detect radiologically. This paper assesses the value of bone radioscintigraphy in relation to radiological examination. The patterns of tracer uptake in the spine were recorded in 16 patients in whom established ankylosing spondylitis was complicated by pseudarthrosis. Twenty such lesions were identified in 16 patients, mostly occurring at one level in a junctional region of the spine. Four patients had two lesions. Standard radiography failed to demonstrate this abnormality in seven patients and in these, tomography was required to confirm the scintigraphic findings. On the other hand, bone scanning was much less accurate in detecting the minor forms of marginal vertebral end plate destruction (spondylo-discitis) than conventional radiology. This study suggests that 99TcmMDP scanning is a useful primary investigation for the detection of spinal pseudarthrosis in patients with chronic ankylosing spondylitis who suffer late onset back pain.