Peripheral arterial missile embolization: a case report and 22-year literature review

The present case report is that of an air pistol missile injury with perforation of a common femoral artery and subsequent arterioarterial embolization to the anterior tibial artery. Included in this report is a review and analysis of a 22-year experience in the vascular trauma literature with missile injuries resulting in cardioarterial or arterioarterial embolization. In-depth analysis of this collective literature review revealed small weapon caliber (79%), usually .22. Soft tissue tamponade at the injury site in the form of mediastinal hematoma, retroperitoneal hematoma, or hemopericardium preventing exsanguination occurred in 37% of cases. Cardiac and thoracic aortic entry sites represented 70% of the series with distinct patterns of peripheral vascular embolization found resulting from anatomic relationships and laminar flow. Diagnostic evaluation by means of remote x-ray screening documented 86% of the emboli and was supplemented with arteriographic studies in 36%. Direct transverse arteriotomy overlying the projectile was favored; most of the delayed embolectomies stemmed from a failure to recognize those patients with peripheral embolization and a compensated asymptomatic limb. An appropriate management plan and diagnostic algorithm for this rare vascular phenomenon have been generated by this study.     

Opposing Effects of Prior Infection versus Prior Vaccination on Vaccine Immunogenicity against Influenza A(H3N2) Viruses

Prior vaccination can alternately enhance or attenuate influenza vaccine immunogenicity and effectiveness. Analogously, we found that vaccine immunogenicity was enhanced by prior A(H3N2) virus infection among participants of the Ha Nam Cohort, Viet Nam, but was attenuated by prior vaccination among Australian Health Care Workers (HCWs) vaccinated in the same year. Here, we combined these studies to directly compare antibody titers against 35 A(H3N2) viruses spanning 1968–2018. Participants received licensed inactivated vaccines containing A/HongKong/4801/2014 (H3N2). The analysis was limited to participants aged 18–65 Y, and compared those exposed to A(H3N2) viruses circulating since 2009 by infection (Ha Nam) or vaccination (HCWs) to a reference group who had no recent A(H3N2) infection or vaccination (Ha Nam). Antibody responses were compared by fitting titer/titer-rise landscapes across strains, and by estimating titer ratios to the reference group of 2009–2018 viruses. Pre-vaccination, titers were lowest against 2009–2014 viruses among the reference (no recent exposure) group. Post-vaccination, titers were, on average, two-fold higher among participants with prior infection and two-fold lower among participants with 3–5 prior vaccinations compared to the reference group. Titer rise was negligible among participants with 3–5 prior vaccinations, poor among participants with 1–2 prior vaccinations, and equivalent or better among those with prior infection compared to the reference group. The enhancing effect of prior infection versus the incrementally attenuating effect of prior vaccinations suggests that these exposures may alternately promote and constrain the generation of memory that can be recalled by a new vaccine strain.     

Effect of bupivacaine on intervertebral disc cell viability

Background contextBupivacaine is a local anesthetic commonly used to relieve or control pain in interventional spine procedures. Bupivacaine has been shown to be toxic to articular cartilage, which has similarities to intervertebral disc (IVD) cartilage, raising concern over a potentially negative effect of bupivacaine on the disc.PurposeTo determine bupivacaine's effect on cell viability of IVD cells in vitro and to elucidate whether this is through apoptosis or necrosis.Study designIn vitro controlled study of bupivacaine effect on cell viability in human and rabbit IVD cells.SubjectsRabbit annulus fibrosus (AF) tissue, nucleus pulposus (NP) cells, and knee articular chondrocytes were isolated from New Zealand white rabbits. Human AF and NP cells were isolated from stage 3 to 4 degenerative disc surgical specimens.Outcome measuresCell viability was assessed after exposure to bupivacaine via trypan blue staining or flow cytometry.MethodsAnnulus fibrosus and NP cells were grown in monolayer and alginate beads, respectively, to simulate their physiologic environment. The cells were then exposed to bupivacaine or saline control at 60 and 120 minutes and examined for cell viability.ResultsRabbit NP cell death demonstrated a time and dose dependence in response to bupivacaine. In addition, cell death was greater than that observed for articular chondrocytes. Rabbit AF tissue also demonstrated increased cell death in response to bupivacaine exposure. Human NP cells demonstrated time-dependent cell death, with greater necrosis than apoptosis. Annulus fibrosus cells grown in monolayers also resulted in similar effects, with greater necrosis rather than apoptosis.ConclusionsDespite its pain relieving properties, bupivacaine decreases cell viability in rabbit and human disc cells in a time-dependent manner. In addition, the changes observed are greater than that seen for articular chondrocytes. This increase in cell death appears to be related to an increase in necrosis rather than apoptosis. Whether bupivacaine exerts similar effects in vivo or how this relates to overall clinical outcome remains to be explored.     

Physiologic upper limit of pore size in the blood-tumor barrier of malignant solid tumors

Background  

The existence of large pores in the blood-tumor barrier (BTB) of malignant solid tumor microvasculature makes the blood-tumor barrier more permeable to macromolecules than the endothelial barrier of most normal tissue microvasculature. The BTB of malignant solid tumors growing outside the brain, in peripheral tissues, is more permeable than that of similar tumors growing inside the brain. This has been previously attributed to the larger anatomic sizes of the pores within the BTB of peripheral tumors. Since in the physiological state in vivo a fibrous glycocalyx layer coats the pores of the BTB, it is possible that the effective physiologic pore size in the BTB of brain tumors and peripheral tumors is similar. If this were the case, then the higher permeability of the BTB of peripheral tumor would be attributable to the presence of a greater number of pores in the BTB of peripheral tumors. In this study, we probed in vivo the upper limit of pore size in the BTB of rodent malignant gliomas grown inside the brain, the orthotopic site, as well as outside the brain in temporalis skeletal muscle, the ectopic site.     

The epidemiology of typhoid fever in the Dong Thap Province, Mekong Delta region of Vietnam

A population-based surveillance for typhoid fever was conducted in three rural communes of Dong Thap Province in southern Vietnam (population 28,329) for a 12-month-period starting on December 4, 1995. Cases of typhoid fever were detected by obtaining blood for culture from residents with fever > or = 3 days. Among 658 blood cultures, 56 (8.5%) were positive for Salmonella typhi with an overall incidence of 198 per 10(5) population per year. The peak occurrence was at the end of the dry season in March and April. The attack rate was highest among 5-9 year-olds (531/10(5)/year), and lowest in > 30 year-olds (39/10(5)/year). The attack rate was 358/10(5)/year in 2-4 year-olds. The isolation of S. typhi from blood cultures was highest (17.4%) in patients with 5 to 6 days of fever. Typhoid fever is highly endemic in Vietnam and is a significant disease in both preschool and school-aged children.     

Prevalence,treatment, and outcome of heart disease in live-born children: A prospective analysis of 91,823 live-born children

Summary All 91,823 children born in 1980 in Bohemia (population 6.314 million; area 52,478 square kilometers) were examined at least four times during infancy and at the age of three and four years. All children who died were autopsied and those with heart disease were selected. A total of 779 children (8.223/1000 live births) were suspected by provincial pediatric cardiologists of having a heart disease. All of these were examined at the age of four years at our Center of Pediatric Cardiology. At this age heart disease was proved in 613 alive or decreased children (6.676/1000 live births), congenital cardiac malformations in 589 (6.415/1000 live births), and cardiomyopathies in 24. The most frequent congenital heart defects (CHD) were ventricular septal defect (VSD) (31.41%), atrial septal defect (ASD) (11.37%), aortic stenosis (AS) (7.64%), pulmonary stenosis (PS) (7.13%), coarctation of the aorta (CoA) (5.77%), and transposition of the great arteries (TGA) (5.43%), followed by persistent ductus arteriosus (PDA) (4.75%), atrioventricular septal defect (AVSD) and hypoplastic left heart syndrome (HLHS) (4.07% each), tetralogy of Fallot (TF) (3.56%), and pulmonary atresia (PA) (2.38%). A prevalence of less than 0.1/1000 live births was found for the remaining cardiovascular defects.One hundred fifty-nine (25.9%) patients were admitted to our highly specialized center, 116 (19.7%) catheterized and 85 (13.9%) treated surgically, during the first four years of life. A total of 440 (71.8%) patients survived the fourth year of life. The percentage of deaths was 25.6% among those with congenital heart diseases and 71% with cardiomyopathies. The overall mortality rate was 27% in surgically and 26% in medically treated patients.     

Second malignant neoplasms following childhood Hodgkin's disease: treatment and splenectomy as risk factors

The risk of second malignant neoplasm (SMN) was evaluated in 979 children with Hodgkin's disease. This cohort was diagnosed between 1955 and 1979 at one of the institutions of the Late Effects Study Group. Solid tumors, non-lymphocytic leukemia, and non-Hodgkin's lymphoma (NHL) developed in 18, 17, and 3 patients, respectively. The estimated cumulative probability of developing any SMN was 2% at 5 years from diagnosis, 5% at 10 years, and 9% at 15 years. The incidence is ninefold greater than the risk of acquiring cancer in 19 year-olds, the median age at which the diagnosis of SMN was made in this study population. For leukemia and NHL the corresponding probabilities were 1%, 3%, and 4% for the group as a whole but were increased (2%, 6%, and 8%) in patients who had suffered one or more recurrences. In order to analyze the risk of leukemia and NHL associated with alkylating agent chemotherapy, each patient was assigned a score of one for each alkylating agent administered for a 6-month period. Scores of 2, 4, 6, and 8 were associated with probabilities of leukemia or NHL of 2%, 3%, 6%, and 10%, respectively. In a multivariate analysis for leukemia/lymphoma that included AAD score, stage, and splenectomy, the effect of AAD score and splenectomy did not change substantially compared to the univariate results. AAD score remained statistically significant (P = .0001), and splenectomy was of borderline significance (P = .09). Of the 18 solid tumor SMNs, 15 developed within the field of radiation, and one other developed in tissue irradiated 34 years earlier for hemangioma. This study of a large and unselected group of children with Hodgkin's disease who received a variety of therapies demonstrates that children are as likely as adults to develop acute leukemia after alkylating agents and solid tumors in the field of radiation therapy.     

Field trials of three concentrations of Laginex as biological larvicide compared to Vectobac-12AS as a biocontrol agent for Culex quinquefasciatus

Laginex AS Biological Larvicide (Lagenidium giganteum) and Vectobac-12AS (Bacillus thuringiensis var. israelensis) were compared in plastic pools containing laboratory-reared Culex quinquefasciatus larvae located in a wooded area in Panama City, FL, in August and September 1997. The pools were dipped at 2-day intervals to assess larval control. Sentinel larvae in screen-sided cups were added to all treatment and control pools at 4-day intervals and evaluated for infection at 48 h. Laginex produced larval control up to 20 days as compared to the Vectobac-12AS compound, which required retreatment by the 10th day. The most effective control was attained by the Laginex 25 treatment, which reduced larvae in the pools by 100% for 22 days. Control in the Laginex 15 and Laginex 35 treatments dropped to 90% and 74% at day 13 and day 9, respectively. The numbers of infected larvae remained above 50% as larval control was assessed, but dropped and fluctuated when water temperatures were lowered at the onset of cold weather. Organic pollution did not prove to be a significant factor in the evaluations.