Fixation of small tibial avulsion fracture of the posterior cruciate ligament using the double bundles pull-through suture method.

BACKGROUND: Avulsion of the tibial insertion of the posterior cruciate ligament is commonly repaired via open reduction and internal fixation with a screw, Kirschner's wire, and suture. In the case of a major bony fragment, this technique is adequate to achieve rigid fixation. In the case of an avulsion fracture with a small bony fragment, however, it is not uncommon to break the bone fragment during screw fixation. We describe a new technique for fixation of an avulsion fracture with a small bony fragment. The technique uses a double bundles pull-through suture technique that repairs the anterolateral and posteromedial components of the posterior cruciate ligament simultaneously. METHODS: From March 1994 through May 1997, 12 patients with small tibial avulsion fractures of the posterior cruciate ligament were treated using this technique. RESULTS: At an average of 18 months after surgery (range, 12-24 months), the preliminary clinical and radiographic results were satisfactory. Eleven patients could return to the same or a higher level of preinjury sports activity. According to the International Knee Documentation Committee rating system, 10 of the 12 patients had normal or nearly normal ratings. CONCLUSION: The double bundles pull-through suture technique can avoid the risk of breakage of the small bony fragment, does not require the removal of hardware, and can achieve adequate repair in the anatomic situation. Our clinical experience suggests that it is a good choice for fixation in cases of avulsion fracture with a small bony fragment.     

Long-term ex vivo maintenance and expansion of transplantable human hematopoietic stem cells.

We have developed a stromal-based in vitro culture system that facilitates ex vivo expansion of transplantable CD34(+) thy-1(+) cells using long-term hematopoietic reconstitution in severe combined immunodeficient-human (SCID-hu) mice as an in vivo assay for transplantable human hematopoietic stem cells (HSCs). The addition of leukemia inhibitory factor (LIF) to purified CD34(+) thy-1(+) cells on AC6.21 stroma, a murine bone marrow-derived stromal cell line, caused expansion of cells with CD34(+) thy-1(+) phenotype. Addition of other cytokines, including interleukin-3 (IL-3), IL-6, granulocyte-macrophage colony-stimulating factor, and stem cell factor, to LIF in the cultures caused a 150-fold expansion of cells retaining the CD34(+) thy-1(+) phenotype. The ex vivo-expanded CD34(+) thy-1(+) cells gave rise to multilineage differentiation, including myeloid, T, and B cells, when transplanted into SCID-hu mice. Both murine LIF (cannot bind to human LIF receptor) and human LIF caused expansion of human CD34(+) thy-1(+) cells in vitro, suggesting action through the murine stroma. Furthermore, another human HSC candidate, CD34(+) CD38(-) cells, shows a similar pattern of proliferative response. This suggests that ex vivo expansion of transplantable human stem cells under this in vitro culture system is a general phenomenon and not just specific for CD34(+) thy-1(+) cells.     

Evidence that phospholipid oxidation products and/or platelet-activating factor play an important role in early atherogenesis : in vitro and In vivo inhibition by WEB 2086.

The goal of the present studies was to determine whether phospholipid oxidation products and/or platelet-activating factor (PAF) are mediators of early atherogenesis in vivo. Monocyte-endothelial cell interactions have been shown to play an important role in early atherogenesis. We and others have demonstrated that PAF and phospholipid oxidation products, present in atherosclerotic lesions, including 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC), 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine (PGPC), and 1-palmitoyl-2-epoxyisoprostane E(2)-sn-glycero-3-phosphocholine (PEIPC), mediate the activation of monocytes and/or endothelial cells in vitro. Previous studies have shown that the action of PAF and PAF-like ether-containing phospholipids was inhibited by WEB 2086. We now demonstrate that pretreatment of human aortic endothelial cells with WEB 2086 (10 micromol/L) and several other PAF antagonists before treatment with POVPC and PEIPC but not PGPC prevented the activation of the endothelial cells to bind monocytes. We present evidence to suggest that this inhibition is not mediated by the PAF receptor. The role of bioactive oxidized phospholipids in fatty streak formation was tested using C57BL/6J LDL R-/- mice fed a chow or Western diet for 5 weeks with or without WEB 2086 mixed with drinking water. Quantitative electrospray ionization mass spectrometry showed similar concentrations of WEB 2086 in the plasma of mice on both diets ( approximately 4 to 5 micromol/L); this concentration was inhibitory in vitro. Administration of WEB 2086 did not affect the lipid composition of mouse plasma. However, fatty streak formation was reduced by 62% in animals fed a Western diet, whereas no change was observed in the small lesions of mice on a chow diet. These studies provide evidence that PAF and/or PAF-like phospholipid oxidation products are important mediators of atherosclerotic lesion development in vivo and that specific receptor antagonists for these molecules may represent a novel therapeutic modality.     

Emergency Department Observation of Poisoned Patients: How Long Is Necessary?

OBJECTIVE: To compare the emergency physician disposition decisions after observation periods of two, four, and six hours in a single cohort of ED patients with acute intentional ingestion to determine the accuracy of disposition decisions at two and four hours relative to the six-hour period of observation. METHODS: This was a prospective observational study at two university hospital EDs. Study participants were patients with potentially toxic oral ingestions occurring less than six hours prior to ED presentation. Patients with isolated recreational drug or ethanol use were excluded. Structured data forms were completed at presentation, and two, four, and six hours later. Data included signs and symptoms consistent with toxic ingestion, physical examination, laboratory determinations, medications ingested, treatment, and suicide risk. At two and four hours, physicians were asked to determine whether they thought the patient was safe for medical clearance. These patients continued to be observed for six hours. The main outcome was whether patients initially thought to be appropriate for early medical clearance were ultimately cleared at six hours. RESULTS: There were 260 patients enrolled: 28 were immediately admitted to the hospital and 17 were immediately discharged; 215 entered ED observation. Patients had a mean age of 24 years; 55% were female; 50% were suicidal; 17% had toxidromes. Of the 215 observed patients, 106 (49%) were deemed safe for early medical clearance at two hours. All 106 were ultimately cleared at six hours (100%, 95% CI = 97% to 100%). Of the 109 not safe for early medical clearance at two hours, 61 (56%) were deemed safe for early medical clearance at four hours; all 61 were subsequently discharged at six hours (100%; 95% CI = 95% to 100%). Overall, 167 of 215 (77%) observed overdose patients were deemed safe for early medical clearance after two or four hours of observation. All 167 were ultimately cleared at six hours (100%; 95% CI = 98.2% to 100%). CONCLUSIONS: A large subset of overdose patients who are medically cleared after six hours of observation can be identified within two to four hours of presentation. No patient who was believed to be safe for medical clearance at either two or four hours had a complication within the six-hour time period (95% CI = 0% to 1.8%). These data suggest that asymptomatic patients with selected acute intentional ingestions can be released from medical observation in less than six hours.     

Diagnosis of respiratory tract viruses in 24 h by immunofluorescent staining of shell vial cultures containing Madin-Darby Canine Kidney (MDCK) cells.

Nine hundred and seventy-eight clinical specimens were examined taken from patients with respiratory tract viruses (RV)-like syndrome between November 1996 and July 1998. The study was undertaken to evaluate the effectiveness of centrifuge-enhanced shell vial cultures (SVC) containing Madin-Darby Canine Kidney (MDCK) cells, combined with immunofluorescent (IF) staining in 24 h. This technique rapidly detects and identifies respiratory tract viruses. The conventional tube culture system with multiple cell lines would ordinarily detect RV within 3-30 days. The SVC/IF method using single cell line (MDCK cells) allowed detection of 81.5% of influenza A virus, 72% of parainfluenza virus, 82.6% of respiratory syncytial virus (RSV) and 79.6% of adenovirus in 24 h.     

An epidemic of enterovirus 71 infection in Taiwan. Taiwan Enterovirus Epidemic Working Group.

BACKGROUND: Enteroviruses can cause outbreaks of hand-foot-and-mouth disease (characterized by vesicular lesions on the hands, feet, and oral mucosa) or herpangina, usually without life-threatening manifestations. In 1998 an epidemic of enterovirus 71 infection caused hand-foot-and-mouth disease and herpangina in thousands of people in Taiwan, some of whom died. METHODS: We assessed the epidemiologic aspects of this outbreak. Cases of hand-foot-and-mouth disease or herpangina in ambulatory patients were reported to the Taiwan Department of Health by a mean of 818 sentinel physicians. Severe cases in hospitalized patients were reported by 40 medical centers and regional hospitals. Viruses were isolated by 10 hospital laboratories and the department of health. RESULTS: The sentinel physicians reported 129,106 cases of hand-foot-and-mouth disease or herpangina in two waves of the epidemic, which probably represents less than 10 percent of the estimated total number of cases. There were 405 patients with severe disease, most of whom were five years old or younger; severe disease was seen in all regions of the island. Complications included encephalitis, aseptic meningitis, pulmonary edema or hemorrhage, acute flaccid paralysis, and myocarditis. Seventy-eight patients died, 71 of whom (91 percent) were five years of age or younger. Of the patients who died, 65 (83 percent) had pulmonary edema or pulmonary hemorrhage. Among patients from whom a virus was isolated, enterovirus 71 was present in 48.7 percent of outpatients with uncomplicated hand-foot-and-mouth disease or herpangina, 75 percent of hospitalized patients who survived, and 92 percent of patients who died. CONCLUSIONS: Although several enteroviruses were circulating in Taiwan during the 1998 epidemic, enterovirus 71 infection was associated with most of the serious clinical manifestations and with nearly all the deaths. Most of those who died were young, and the majority died of pulmonary edema and pulmonary hemorrhage.     

Prenatal diagnosis of a fetus with distal 10q trisomy.

Distal 10q trisomy is a well-defined but rare syndrome. Most cases are diagnosed in infancy or in childhood and rarely include prenatal findings. We present a case of fetal distal 10q trisomy with abnormal prenatal sonographic findings. A 19-year-old primigravida was referred for genetic counselling at 18 gestational weeks because her husband had a familial history of congenital anomalies. Genetic amniocentesis was thus performed and showed fetal distal 10q trisomy (10q24.1-->qter), 46,XX,der(22)t(10;22)(q24.1;p11.2)pat, resulting from paternal t(10;22) reciprocal translocation. Level II ultrasonograms further demonstrated bilateral hydronephrosis, ventricular septal defect and facial dysmorphism ascertained by three-dimensional ultrasound. The pregnancy was terminated at 22 gestational weeks. Post-mortem autopsy confirmed the sonographic findings. We suggest that abnormal prenatal sonographic findings such as cardio-vascular, renal and facial malformations should alert cytogeneticists to search for subtle chromosomal abnormalities.     

Complications of liner locking system in MicroStructured Omnifit acetabular components: A radiographic evaluation of 887 hips followed for 5-10 years

We evaluated 887 hips in 672 patients with uncemented MicroStructured Omnifit acetabular components for liner locking complications. We found 2 types of radiographic signs of liner locking system complications in 7 hips, developing between 2 and 4 years postoperatively. The incidence of liner locking system complications was 0.8% using this modular acetabular component. We recommend that a patient who has received a total hip arthroplasty including a MicroStructured Omnifit acetabular component should be monitored frequently for radiographic signs of liner locking system complications, especially with a polyethylene thickness of less than 8 mm.     

Antimutagenicity of ethanol extracts of bee glue against environmental mutagens.

The antimutagenicity of ethanol extracts of bee glue (propolis) (EEBG) was evaluated, using Salmonella typhimurium strain TA98 as a test model, against two direct mutagens, 4-nitro-O-phenylenediamine (4-NO) and 1-nitropyrene (1-NP), and two indirect mutagens, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and benzo[a]pyrene (B[a]P) with S9 mix. EEBG was shown to suppress the mutagenicity of these compounds in a dose-dependent fashion. To delineate the mechanism of action of the antimutagenic effects of EEBG on the two indirect mutagens IQ and B[a]P, two possible points of blocking were considered: (1) cytochrome P-450 activity (route 1) and (2) interaction with microsome-generated proximate mutagens to generate an inactive complex (route 2). Our results clearly demonstrated, at a very low dose, remarkable suppression of the mutagenicity of both compounds by inhibiting either route 1 or route 2 pathway. Further studies indicated that EEBG was capable of inhibiting both the activities of hepatic cytochrome P-450 IA1-linked 7-ethoxyresorufin-O-deethylase (EROD) and IA 2-linked 7-ethoxycoumarin-O-deethylase (ECD) in a similar dose-dependent manner. Taken together, we demonstrated that EEBG was a good inhibitor for mutagenicity of direct mutagens, 1-NP and 4-NO, as well as for the indirect mutagens IQ and B[a]P in the presence of S9 mix via inactivation of microsomal enzyme activities (e.g. EROD and ECD) or antagonizing metabolic generation of the proximate mutagens of IQ and B[a]P.