One-Way Self-Expanding Rod in Neuromuscular Scoliosis: Preliminary Results of a Prospective Series of 21 Patients

Fusionless techniques for the treatment of neuromuscular early-onset scoliosis (EOS) are increasingly used to preserve spinal and thoracic growth and to postpone posterior spinal fusion (PSF). These techniques have greatly improved thanks to magnetically controlled growing rods, which allow the avoidance of repeated surgery. However, the surgery-related complication rate remains high. The objective of the current study was to report the preliminary outcomes of 21 patients with neuromuscular EOS who were treated with a 1-way self-expanding rod (OWSER). This device was designed to avoid repeated surgery and preserve spinal and thoracic growth thanks to its free rod sliding.

Preconceptional and prenatal exposure to air pollution increases incidence of childhood pneumonia: A hypothesis of the (pre-)fetal origin of childhood pneumonia

BACKGROUND

Increasing evidence has linked childhood pneumonia with early exposure to ambient air pollution. However, the impact of exposure to air pollutants before birth is unclear.

OBJECTIVE

To further clarify whether exposure to a particular pollutant during preconceptional and prenatal periods, may pose a higher risk of developing childhood pneumonia.

METHODS

This case-control cohort study consisted of 1510 children aged 0-14 years in Changsha, China between 2017 and 2019. Data of children's history of pneumonia and blood biomarkers were obtained from the XiangYa Hospital records. Each child's exposure to air pollutants, including nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and particulate matter with an aerodynamic diameter ≤ 10 µm (PM₁₀), was calculated using data from ten air pollution monitoring stations. A multivariate logistic regression model was used to quantify the relationship between childhood pneumonia and exposure to ambient air pollution during the preconceptional and prenatal periods.

RESULTS

Childhood pneumonia was significantly associated with preconceptional and prenatal exposure to the industrial-related air pollutant, SO₂, for 1 year before conception, for 3 months before conception and for the entire pregnancy, with ORs(95% CI)= 4.01(3.17-5.07), 4.06(3.29-5.00) and 6.51(4.82-8.79). Also, children who were sick with pneumonia had higher white blood cell and neutrophil counts, and children with low eosinophil count or hemoglobin are likely to get pneumonia. Sensitivity analysis showed that boys, and children in high temperature area were susceptible to the effect of both preconceptional and prenatal exposure to industrial SO₂.

CONCLUSION

Preconceptional and prenatal exposure to industrial-related air pollution plays a significant role in the incidence and progression of childhood pneumonia, supporting the hypothesis of "(pre-)fetal origin of childhood pneumonia".

Audio-computer-assisted survey interview and patient navigation to increase chronic viral hepatitis diagnosis and linkage to care in urban health clinics

Intravenous drug use and sexual practices account for 60% of hepatitis C (HCV) and B (HBV) infection. Disclosing these activities can be embarrassing and reduce risk reporting, blood testing and diagnosis. In diagnosed patients, linkage to care remains a challenge. Audio-computer-assisted survey interview (Audio-CASI) was used to guide HCV and HBV infection testing in urban clinics. Risk reporting, blood testing and serology results were compared to historical controls. A patient navigator (PN) followed up blood test results and provided patients with positive serology linkage to care (LTC). Of 1932 patients surveyed, 574 (30%) were at risk for chronic viral hepatitis. A total of 254 (44.3%) patients were tested, 34 (13.5%) had serology warranting treatment evaluation, and 64% required HBV vaccination. Of 16 patients with infection, seven HCV and three HBV patients started treatment following patient LTC. Of 146 HBV-naïve patients, 70 completed vaccination. About 75% and 49% of HCV antibody and HBV surface antigen-positive patients were born between 1945 and 1965. Subsequently, automated HCV testing of patients born between 1945 and 1965 was built into our hospital electronic medical records. Average monthly HCV antibody testing increased from 245 (January-June) to 1187 (July-October). Patient navigator directed LTC for HCV antibody-positive patients was 61.6%. In conclusion, audio-CASI can identify patients at risk for HCV or HBV infection and those in need of HBV vaccination in urban medical clinics. Although blood testing once a patient is identified at risk for infection needs to increase, a PN is useful to provide LTC of newly diagnosed patients.

A CACNA1D mutation in a patient with persistent hyperinsulinaemic hypoglycaemia, heart defects, and severe hypotonia

Congenital hyperinsulinaemic hypoglycaemia (HH) can occur in isolation or it may present as part of a wider syndrome. For approximately 40%-50% of individuals with this condition, sequence analysis of the known HH genes identifies a causative mutation. Identifying the underlying genetic aetiology in the remaining cases is important as a genetic diagnosis will inform on recurrence risk, may guide medical management and will provide valuable insights into β-cell physiology. We sequenced the exome of a child with persistent diazoxide-responsive HH, mild aortic insufficiency, severe hypotonia, and developmental delay as well as the unaffected parents. This analysis identified a de novo mutation, p.G403D, in the proband's CACNA1D gene. CACNA1D encodes the main L-type voltage-gated calcium channel in the pancreatic β-cell, a key component of the insulin secretion pathway. The p.G403D mutation had been reported previously as an activating mutation in an individual with primary hyper-aldosteronism, neuromuscular abnormalities, and transient hypoglycaemia. Sequence analysis of the CACNA1D gene in 60 further cases with HH did not identify a pathogenic mutation. Identification of an activating CACNA1D mutation in a second patient with congenital HH confirms the aetiological role of CACNA1D mutations in this disorder. A genetic diagnosis is important as treatment with a calcium channel blocker may be an option for the medical management of this patient.

Thermoacoustic range verification using a clinical ultrasound array provides perfectly co-registered overlay of the Bragg peak onto an ultrasound image

The potential of particle therapy due to focused dose deposition in the Bragg peak has not yet been fully realized due to inaccuracies in range verification. The purpose of this work was to correlate the Bragg peak location with target structure, by overlaying the location of the Bragg peak onto a standard ultrasound image. Pulsed delivery of 50 MeV protons was accomplished by a fast chopper installed between the ion source and the cyclotron inflector. The chopper limited the train of bunches so that 2 Gy were delivered in [Formula: see text]. The ion pulse generated thermoacoustic pulses that were detected by a cardiac ultrasound array, which also produced a grayscale ultrasound image. A filtered backprojection algorithm focused the received signal to the Bragg peak location with perfect co-registration to the ultrasound images. Data was collected in a room temperature water bath and gelatin phantom with a cavity designed to mimic the intestine, in which gas pockets can displace the Bragg peak. Phantom experiments performed with the cavity both empty and filled with olive oil confirmed that displacement of the Bragg peak due to anatomical change could be detected. Thermoacoustic range measurements in the waterbath agreed with Monte Carlo simulation within 1.2 mm. In the phantom, thermoacoustic range estimates and first-order range estimates from CT images agreed to within 1.5 mm.

Nanoporous surface wetting behavior: the line tension influence

The aim of this work is to develop a physical model to describe the evolution of the apparent contact angle for four different liquids on nanotextured alumina surfaces with different pore radius. The nanoporous alumina templates were fabricated by anodization of Al foil in a 0.3 M oxalic acid solution. Scanning electron microscopy was used to characterize the morphology of the surfaces. The templates are approximately 400 nm in thickness and consist of a well-ordered hexagonal array of uniform radius pores spaced 105 nm apart with pore radii from 12 to 42 nm. The wettability of nanoporous alumina templates was investigated using contact-angle measurements. We measured the contact angles using four liquids: water, ethylene glycol, aniline, and a mixture of ethylene glycol and aniline. We developed a new theoretical model for the contact angle on nanoporous surfaces as a function of the pore radius. This model is based on energy considerations and involves liquid penetration into the nanopores driven by the capillarity (Laplace's law). Because the air is compressed inside the pores, this model also includes the effect of the line tension. This is important because the three-phase line length is greatly enhanced in our nanoporous structures. For example: for a millimeter-sized droplet, the three-phase line around the perimeter of the droplet is a few millimeters long, whereas the total three-phase line within the pores can reach several tens of meters. Using our model, the line-tension value for our nanopore samples is positive and ranges from 4 to 13 × 10(-9) N, which falls within the wide interval from 10(-11) to 10(-5) N quoted in the literature. Nanoporous surfaces may allow the effect of line tension to be visible for micro- to macrodroplets.

Postural control in women with multiple sclerosis: effects of task, vision and symptomatic fatigue

People with multiple sclerosis (MS) often report problems with balance, which may be most apparent during challenging postural tasks such as leaning or reaching, and when relying on non-visual sensory systems. An additional obstacle facing people with MS is a high incidence of symptomatic fatigue (>70%). The purpose of this study was to investigate the changes in balance during upright stance in individuals with mild-to-moderate disability due to MS under normal and restricted vision and different levels of self-reported fatigue. Limb loading asymmetry, sway and magnitude of postural shift in center of pressure, and time-to-contact the stability boundary of the center of mass and center of pressure were assessed during quiet standing and maximal lean and reach tasks. Compared to controls, people with MS displayed greater postural sway, greater loading asymmetry, and shorter time-to-contact during quiet standing. In the postural perturbation tasks the MS group had smaller postural shifts and reduced stability compared to controls in the direction perpendicular to the lean and reach. Limiting vision increased loading asymmetry during quiet standing and postural instability during backward lean in the MS group. Inducing additional fatigue in the MS group did affect postural control in the more challenging balance conditions but had no impact during quiet upright standing. The results of this study indicate subtle changes in postural control during standing in people with mild-to-moderate impairments due to MS.

Differences in pediatric dental services under general anesthesia for Medicaid and military dependent children

PURPOSE

This study's purpose was to compare pediatric dental services provided for Medicaid and military dependent children to determine if differences in dental treatment choices exist based on site and payment method.

METHODS

Subjects included 120 Medicaid patients at the University of Texas Health Science Center at San Antonio and 120 military dependents at Lackland Air Force Base, Texas. Demographic data and treatment information were abstracted for children younger than 6 years old receiving dental treatment under general anesthesia between 2002 and 2006. Data was analyzed using Wilcoxon rank sum, Kruskal-Wallis, and Fisher's exact tests.

RESULTS

The Medicaid recipients were younger (40.2 vs 49.8 months, P<.001) and more likely to be Hispanic (78% vs 30%, P<.001). The means of decayed teeth, fillings, and stainless steel crowns did not differ between sites. Medicaid children received more composite fillings (P<.001), fewer amalgam fillings (P<.001), fewer pulp therapies (P<.001), more extractions (P=.01), and fewer sealants (P<.001). Age and gender did not affect decay rates, but those of Hispanic ethnicity did experience more decay than non-Hispanics (9.5 vs 8.6, P=.02).

CONCLUSION

This study found no difference in the number of less conservative, albeit more costly, procedures performed with Medicaid children at a university compared to military dependents at a military base.

ESI+ MS/MS confirmation of canine ivermectin toxicity

Ivermectin is a semisynthetic macrocyclic lactone anthelmintic of the avermectin family derived from Streptomyces fermentation products. Avermectins are used as antiparasitic agents in domestic animals; although considered relatively safe, one must consider animal species, breed, weight, and age in dosage determinations.In January 2006, two canines were presented to the UK Livestock Disease Diagnostic Center after dying from suspected ivermectin overdoses [30-50 mg/kg body weight]. To confirm this clinical diagnosis we developed a rapid, sensitive semiquantitative ElectroSpray Ionization-Mass Spectrometry (ESI/MS) method for ivermectin in canine tissue samples. Pharmaceutical ivermectin contains two ivermectins differing by a single methyl group, and each compound forms interpretation-confounding adducts with tissue Na(+) and K(+) ions. We now report that ivermectin administration was clearly confirmed by comparison with standard and dosage forms of ivermectin, and simple proportionalities based on mass spectral intensity of respective molecular ions allowed semiquantitative estimates of injection site tissue concentrations of 20 and 40 microg/g tissue (wet weight) in these animals, consistent with the history of ivermectin administration and the clinical signs observed.There is a distinct need for both rapid detection and confirmation of toxic exposures in veterinary diagnostics, whether for interpretation of clinical cases antemortem or for forensic reasons postmortem. It is vital that interpreters of analytical results have appropriate guidance in the scientific literature and elsewhere so as to enable clear-cut answers. The method presented here is suitable for routine diagnostic work in that it allows rapid extraction of ivermectin from tissue samples, avoids the need for high-performance liquid chromatography and allows ready interpretation of the multiple ivermectin species seen by ESI(+) MS/MS in samples originating from veterinary dosage forms.

Spin waves and quantum criticality in the frustrated XY pyrochlore antiferromagnet Er2Ti2O7

We report detailed measurements of the low temperature magnetic phase diagram of Er2Ti2O7. Heat capacity and time-of-flight neutron scattering studies of single crystals reveal unconventional low-energy states. Er3+ magnetic ions reside on a pyrochlore lattice in Er2Ti2O7, where local XY anisotropy and antiferromagnetic interactions give rise to a unique frustrated system. In zero field, the ground state exhibits coexisting short and long-range order, accompanied by soft collective spin excitations previously believed to be absent. The application of finite magnetic fields tunes the ground state continuously through a landscape of noncollinear phases, divided by a zero temperature phase transition at micro{0}H{c} approximately 1.5 T. The characteristic energy scale for spin fluctuations is seen to vanish at the critical point, as expected for a second order quantum phase transition driven by quantum fluctuations.

Nanomechanical properties of a Ni nanodot-patterned surface

Nanomechanical properties of a Ni nanodot-patterned surface (NDPS) on a Si substrate were investigated using nanoindentation. The Ni NDPS was fabricated by thermal evaporation of Ni through a porous anodized aluminum oxide template onto a Si substrate. Plan-view transmission electron microscopy and nanobeam diffraction were used to characterize the Ni nanodot crystal structure. Scanning electron microscopy and atomic force microscopy were used to characterize the morphology and deformation of the Ni nanodots before and after nanoindentation. The elastic modulus and hardness of the Ni nanodots were found to be 159 ± 22 and 7.7 ± 1.0 GPa, respectively. The critical shear stress for initiating plastic deformation in the Ni nanodot was estimated to be 8.3 ± 1.0 GPa, which is close to the theoretical shear strength of 7.6 GPa in dislocation-free single crystal Ni.

Clear cell sarcoma (melanoma of soft parts): The Royal Marsden Hospital experience

INTRODUCTION

Clear cell sarcoma (CCS) is a rare tumour with a propensity for local recurrence and nodal metastasis. About 300 cases have been reported, thus further clarification regarding the course and outcome of the disease is required.

METHODS

Patients with a histopathologic diagnosis of CCS were identified from prospective histopathology and sarcoma databases and supplemented with a retrospective analysis of the patients' hospital records.

RESULTS

Between 1990 and 2005, a total of 72 patients with a diagnosis of CCS were identified, 35 having been referred for management and 37 having been referred for histopathologic opinion. The median age was 39 years (range 5-90 years). Of the 35 patients referred to the Royal Marsden Hospital for management, 23% developed local recurrence or in-transit metastases at a median of 9 months (2-79 months) after resection of the primary, and nodal or distant metastatic disease was seen in 63% after 14 months (range 0-177 months). Five- and 10-year survival were 52% and 25%, respectively.

CONCLUSIONS

CCS has a number of similarities with melanoma, particularly in its peripheral distribution and propensity for nodal disease. Wide excision with clear margins offers the best chance of cure. Local recurrence and regional metastases are common, and are almost always followed by distant metastases and death.

Spin waves in nickel nanorings of large aspect ratio

The spin dynamics of high-aspect-ratio nickel nanorings in a longitudinal magnetic field have been investigated by Brillouin spectroscopy and the results are compared with a macroscopic theory and three-dimensional micromagnetic simulations. Good agreement is found between the measured and calculated magnetic field dependence of the spin wave frequency. Simulations show that as the field decreases from saturation, the rings switch from a "bamboo" to a novel "twisted bamboo" state at a certain critical field, and predict a corresponding dip in the dependence of the spin wave frequency on the magnetic field.

Redox-active monolayers on nano-scale silicon electrodes

Uniform arrays of nano-scale electrolyte-molecule-silicon capacitors have been successfully fabricated. This was done by a combination of reactive ion etch and a selective wet etch through an anodic aluminium oxide mask to form nano-holes in silicon oxide/silicon nitride insulator layers on silicon. Self-assembled monolayers of 4-ferrocenylbenzyl alcohol were then attached to the exposed silicon surfaces at the bottom of the nano-holes. Characterization by conventional capacitance and conductance techniques showed very high capacitance and conductance peaks near -0.6 V, that were attributed to the charging and discharging of electrons into and from discrete levels in the monolayer owing to the presence of the redox-active ferrocenes.

Mesenteric ischemia: an unusual presentation of traumatic intrahepatic arterioportal fistula

Traumatic hepatic arterioportal fistulae (APF) are described infrequently as sequelae of hepatic trauma. These anomalies are usually associated with blunt hepatic trauma or iatrogenic injury. The majority of APF present within weeks to months of injury with gastrointestinal hemorrhage, hemobilia, abdominal pain, and diarrhea. When presenting remotely APFs are associated with portal hypertension, heart failure, gastrointestinal hemorrhage, ascites, and splenomegaly. We report an unusual case of mesenteric ischemia due to an APF that resulted from a penetrating liver injury 20 years before presentation. Successful treatment of the APF was achieved by intravascular catheter occlusion resulting in resolution of symptoms.

Global ischemia induces expression of acid-sensing ion channel 2a in rat brain

Acid-sensing ion channels (ASICs) are ligand-gated cation channels that respond to acidic stimuli. They are expressed throughout the mammalian nervous system. In the peripheral nervous system, ASICs act as nociceptors, responding to the tissue acidosis that accompanies ischemic and inflammatory conditions. The function of ASICs in the central nervous system is not known. In this article, the authors present evidence that transient global ischemia induces ASIC 2a protein expression in neurons that survive ischemia. Western blot analysis with an anti-ASIC 2a antibody revealed up-regulation of an 80 kD protein in ischemic rat brain. Immunohistochemical analysis showed that ASIC 2a protein expression increased in neurons of the hippocampus and cortex. Klenow fragment-mediated labeling of DNA strand breaks determined that ASIC 2a induction did not occur in cells with detectable DNA damage. The current results suggest a possible role for ASICs in mediating a cellular response to ischemia.

Energy loss of fast quarks in nuclei

We report an analysis of the nuclear dependence of the yield of Drell-Yan dimuons from the 800 GeV/c proton bombardment of 2H, C, Ca, Fe, and W targets. Employing a new formulation of the Drell-Yan process in the rest frame of the nucleus, this analysis examines the effect of initial-state energy loss and shadowing on the nuclear-dependence ratios versus the incident proton's momentum fraction and dimuon effective mass. The resulting energy loss per unit path length is -dE/dz = 2.32+/-0.52+/-0.5 GeV/fm. This is the first observation of a nonzero energy loss of partons traveling in a nuclear environment.

Inhibition of mammary epithelial apoptosis and sustained phosphorylation of Akt/PKB in MMTV-IGF-II transgenic mice

IGF-II is a growth factor implicated in human cancers and animal tumor models. While the mitogenic properties of IGF-II are well documented, its ability to suppress apoptosis in vivo has never been proven. We generated independent MMTV-IGF-II transgenic mice to examine the control of epithelial apoptosis at the morphological, cellular and molecular levels during the physiological event of postlactation mammary involution. Transgenic IGF-II expression was achieved in mammary epithelium and increased IGF-II bioactivity was confirmed by phosphorylation of the insulin receptor substrate-1, a signaling molecule downstream of the type I IGF receptor. IGF-II overexpression induced a delay in mammary involution, as evident by increased mammary gland to body weight ratios and persistence of both functionally intact lobulo-alveoli and mammary epithelial cellularity. The delayed mammary involution resulted from a significant reduction in mammary epithelial apoptosis, and not from increased epithelial proliferation. Recombinant IGF-II pellets implanted into involuting mammary glands of wild-type mice provided further evidence that IGF-II protein inhibited local epithelial apoptosis. At the molecular level, phosphorylated Akt/PKB, but not Erk1 or Erk2, persisted in IGF-II overexpressors and temporally correlated with reduced epithelial apoptosis. Levels of the phosphatase PTEN were unaltered in the transgenic tissue suggesting that the maintenance of Akt/PKB phosphorylation resulted from sustained phosphorylation rather than altered dephosphorylation of PIP-3. Together, this data reveal that IGF-II inhibits apoptosis in vivo and this effect correlates with prolonged phosphorylation of Akt/PKB

Comparison of Doppler ultrasound, magnetic resonance angiographic techniques and catheter angiography in evaluation of carotid stenosis

AIM

To compare the accuracy of ultrasound and two magnetic resonance (MR) angiographic techniques with catheter angiography in assessing atherosclerosis at the carotid bifurcation.

MATERIALS AND METHODS

Forty patients with symptomatic carotid stenosis were studied by Doppler ultrasound, time-of-flight MR angiography, contrast-enhanced MR angiography and conventional catheter angiography. The degree of stenosis found on ultrasound and MR angiography was compared with the results of catheter angiography. Four different assessment methods were conducted for the MR angiographic data. Kappa, sensitivity and specificity (with confidence intervals) values were calculated for the US and MR angiography results compared to catheter angiography.

RESULTS

Catheter angiography showed 12 internal carotid artery occlusions (15%), 34 severe (44%), 12 moderate (15%) and 20 mild stenoses (26%), using NASCET criteria. Ultrasound showed 65% sensitivity and 95% specificity in detecting surgically amenable lesions, whilst the MR angiographic techniques had sensitivities varying from 82-100%, and specificities from 95-100%.A moderate kappa value was calculated for the US data, whilst all MR techniques were found to show very good agreement with catheter angiography.

CONCLUSION

This data suggests that MR angiography is more accurate than Doppler ultrasound in defining surgical lesions and has comparable accuracy to catheter angiography. The use of contrast-enhanced MR angiography is useful in certain situations but is not essential in all cases.

Resolution of hormonal markers of ectopic gestation: a randomized trial comparing single-dose intramuscular methotrexate with salpingostomy

OBJECTIVE

To evaluate resolution of serum hCG and progesterone in patients with ectopic pregnancy receiving single-dose intramuscular (IM) methotrexate as compared with those undergoing laparoscopic salpingostomy.

METHODS

In this prospective randomized clinical trial, 75 hemodynamically stable women with a diagnosis of ectopic pregnancy were randomized to treatment with single-dose IM methotrexate (1 mg/kg) or laparoscopic salpingostomy. All women had initial, day 4, and weekly serum hCG and progesterone measurements taken until hCG levels were less than 15 mIU/mL. Methotrexate therapy was repeated if posttreatment day 7 hCG levels did not decrease by 15%, as compared with day 4 levels. Success rate was defined as ectopic resolution without the need for the alternate mode of therapy.

RESULTS

Thirty-eight women were randomized to treatment with methotrexate and 37 to laparoscopic salpingostomy. The mean (+/-standard deviation) time required for serum progesterone concentrations to decrease to less than 1.5 ng/mL was significantly less for laparoscopic salpingostomy than for treatment with methotrexate: 7.8+/-1.7 and 17.6+/-2.2 days, respectively (P < .01). Within each treatment group, serum progesterone levels resolved (less than 1.5 ng/mL) more rapidly than did hCG levels (less than 15 mIU/mL) (P < .01). No further treatment was required once serum progesterone levels had decreased to less than 1.5 ng/mL. Success rates were similar in both groups: 94.7% (36 of 38) for methotrexate and 91.4% (33 of 36) for laparoscopic salpingostomy. Mean time required for hCG concentrations to decrease to less than 15 mIU/mL was significantly less for laparoscopic salpingostomy than for methotrexate therapy: 20.2+/-2.7 and 27.2+/-2.3 days, respectively (P < .05). Additional methotrexate injections were required in 15.8% (6 of 38) of women randomized to methotrexate therapy. Initial serum hCG levels for patients receiving additional methotrexate doses were 4830+/-1588 mIU/mL as compared with 2133+/-393 mIU/mL for women receiving only one dose (P = .07).

CONCLUSION

Serum progesterone levels of less than 1.5 ng/mL are a good predictor of ectopic pregnancy resolution regardless of treatment, and because its return to normal values occurs more rapidly than that of hCG levels, serum progesterone may be a better marker for predicting successful treatment. Although laparoscopic salpingostomy leads to faster resolution of hormonal markers of ectopic gestation, methotrexate is equally successful for treating small unruptured ectopic pregnancies. Initial hCG levels may be a marker for women requiring additional doses of methotrexate.

Functional comparison of specifically cross-linked hemoglobins biased toward the R and T states

Selected functional and spectroscopic properties of two human hemoglobin (HbA0) derivatives that were site-specifically cross-linked in the cleft between beta-chains where 2, 3-bisphosphoglycerate normally binds have been determined to assess the effects of the cross-linking on the behavior of the protein. Trimesoyl tris(3,5-dibromosalicylate) (TTDS) cross-links Hb between beta82Lys residues. The resulting TTDS-Hb exhibits a slower rate of oxygen dissociation and an increased rate of carbon monoxide association than observed for HbA0. The electron paramagnetic resonance (EPR) spectrum of TTDS-HbNO does not exhibit the hyperfine structure that is indicative of significant conformational change despite the fact that the 2,3-bisphosphoglycerate binding site is occupied by the cross-linking reagent. The reactivity of the beta93Cys residues of TTDS-Hb is only slightly decreased relative to that of HbA0. On the other hand, cross-linking Hb between Lys82 and the amino-terminal beta1Val group with trimesoyl tris(methyl phosphate) (TMMP) increases the rate of oxygen dissociation and reduces the rate of CO association relative to the rates observed for HbA0. In addition, the EPR spectrum of the TMMP-HbNO exhibits the three-line hyperfine structure that results from disruption of the proximal His-Fe bond of the alpha-chains, and the accessibility of the betaCys93 residues in this derivative is decreased fourfold. The present results are consistent with the conclusion that the quaternary structure of TTDS-Hb is shifted toward the R state whereas the quaternary structure of TMMP-Hb is shifted toward the T state and provides additional evidence that the identity of the residues involved in intramolecular cross-linking of hemoglobin within the 2,3-bisphosphoglycerate binding site between beta-chains can have a significant influence on the conformational and functional properties of the protein.

Short-term macrophage interleukin-1 response to injected silicone in a rat model

The short-term effects of silicone particles on the ability of splenic and peritoneal macrophages to produce Interleukin-1 (IL-1) were assessed. Lewis rats were divided into three groups. Group 1 animals (n=12) were injected subcutaneously with 2.5 ml of sterile saline; Group 2 animals (n=12) received 2.5 ml of Freund's Complete Adjuvant (FCA); Group 3 animals (n=12) received subcutaneous injections (2.5 ml) of a sonicated slurry comprised of equal parts of FCA and silicone. At days 1, 4, and 7 single-cell suspensions of splenic (10(8) cells/ml) and peritoneal (10(6) cells/ml) macrophages of four animals from each group were prepared. The supernatants from macrophages cultured in the presence or absence of lipopolysaccharide (LPS) were added to IL-1 dependent mouse thymocytes for 72 hrs, and subsequently pulsed with 3H-thymidine. Radioactivity incorporation was determined after 18 hrs. Peritoneal macrophage culture supernatants had significantly higher activity than splenic macrophages and all macrophages stimulated with LPS had significantly higher activity. At days 1 and 7, there were no significant differences in 3H-thymidine uptake. At day 4 there was an elevation of 3H-thymidine uptake from supernatant of peritoneal macrophages treated with FCA/silicone suggesting subcutaneous silicone injection has short-term effects.

Comparison of two methods of bedside blood glucose screening in the NICU: evaluation of accuracy and reliability

Bedside whole blood glucose screening in the NICU has been an accepted method of care for several years. Meters or visually read reagent strips are used in bedside screening, but the reliability and accuracy of these methods are not always established before they are implemented as routine practice in the NICU. A study was conducted to determine which method of bedside whole blood glucose screening was the more accurate: visually read Chemstrip bG reagent strips or the One Touch II meter method. The values obtained were compared with lab analysis of serum glucose, and a correlation study was performed to compare the accuracy and reliability of the values produced by the two methods. One hundred samples were obtained from 38 NICU infants; 63 percent of the 100 samples were compared with lab values. Results revealed that the One Touch II method was more reliable (r = .92) than the Chemstrip bG method (r = .87). Furthermore, the One Touch II results correlated better with lab values when the meter was not operated in the neonatal mode. This study revealed that the One Touch II method appears to provide safe and accurate screening of bedside blood glucose in a high-risk neonatal population.

Catfish stings in Mississippi

We reviewed a series of 83 catfish sting cases from inland hospitals (Belzoni and Indianola) and a coastal hospital (Pascagoula) to identify the type and severity of injury, as well as the type of treatment and its effectiveness. Oral cephalosporin was adequate in treating early infections.

Differentiation of benign and malignant adnexal masses: relative value of gray-scale, color Doppler, and spectral Doppler sonography

OBJECTIVE

The purpose of this study was to evaluate prospectively the relative usefulness of color Doppler, spectral Doppler, and gray-scale sonography in differentiating benign from malignant adnexal masses.

SUBJECTS AND METHODS

A total of 170 adnexal masses in 161 patients were classified prospectively as suggestive of or not suggestive of malignant tumor on the basis of gray-scale morphology, internal flow versus peripheral or no flow, and spectral Doppler pulsatility, as measured by a pulsatility index (PI) threshold of 1.0 and a resistive index (RI) threshold of 0.4.

RESULTS

Surgical pathology revealed 123 benign masses and 46 malignant masses. One malignant mass was confirmed by cytologic evaluation of ascitic fluid. On gray-scale analysis, 46 of the 47 malignant masses were classified as suggestive of tumor, and 76 of the 123 benign masses were classified as not suggestive of tumor (sensitivity, 98%; specificity, 62%; negative predictive value [NPV], 99%; and positive predictive value [PPV], 50%). The use of internal color flow as a predictor of malignant tumor yielded a sensitivity of 77%, a specificity of 69%, an NPV of 89%, and a PPV of 49%. The PI and RI values were significantly lower (p < .0001) in malignant masses than in benign masses, although the values overlapped considerably. For a PI of less than 1.0, sensitivity was 67%, specificity was 66%, NPV was 83%, and PPV was 46%. For an RI of less than 0.4, sensitivity was 24%, specificity was 90%, NPV was 73%, and PPV was 50%.

CONCLUSION

In our series, a gray-scale prediction of benignity was reliable (NPV = 99%), and a prediction of malignancy was unreliable (PPV = 50%). Internal color flow was not useful as a predictor of malignancy (PPV = 49%). Although the absence of internal or peripheral color flow suggested benignity (NPV = 94%), only 17 (16 benign) of the masses (about 10%) had no flow. Spectral Doppler analysis with RI and PI was not useful, as no reliable discriminatory value with both high sensitivity and high specificity could be found for either parameter because of the overlap in values obtained for benign and malignant masses.

CNS-directed case management. Cost and quality in harmony

Preserving the integrity of high quality care in a financially restricted environment is the primary challenge facing healthcare providers. The critical question is which delivery system will use limited resources most efficiently without jeopardizing quality of care? Case management has been identified as a solution that offers the most promise. The case management model at Sioux Valley Hospital was developed to deal proactively with resource-intensive patients with chronic illnesses who have frequent admissions and who create financial risk for the hospital. The authors describe the fiscal and clinical outcomes of these select patients.

Antioxidant MDL 29,311 prevents diabetes in nonobese diabetic and multiple low-dose STZ-injected mice

Recent investigations suggest a role for antioxidants in preventing IDDM. MDL 29,311 (4,4'-[methylenebis(thio)]bis](1,1- dimethylethyl)]-phenol) is an analogue of the antioxidant probucol. Administered as a 1% dietary admixture to female nonobese diabetic mice from 4 to 24 wk of age, MDL reduced the prevalence of diabetes from 49 to 4% at 24 wk of age (n = 50-61/group). Discontinuation of treatment at 24 wk of age did not result in a rapid onset of diabetes. Probucol (1%) did not prevent diabetes. Initiating MDL treatment at 4 or 8 wk of age was more effective (19 and 17%, respectively, compared with 60% in control mice) than initiating treatment at 12 wk of age (30% diabetic; n = 28-35/group). A lower dose of MDL (0.1%), started at 4 wk of age, decreased the prevalence of diabetes to 36%. Histopathology indicated that MDL did not prevent insulitis. MDL (0.1%) also was evaluated in combination with immunosuppressants. Compared with control mice (65% diabetic), the combination of MDL and deflazacort was more effective (21% diabetic) than either agent alone (39% diabetic for MDL and 59% diabetic for deflazacort), whereas the effectiveness of MDL, cyclosporin, and MDL plus cyclosporin was similar (39, 38, and 34% diabetic, respectively). In another model of IDDM, the multiple-low-dose streptozocin-injected mouse, MDL (1%) also reduced the prevalence of diabetes when administered beginning 8 wk before streptozocin (55% diabetic vs. 100% of control mice; n = 20-25/group). Probucol (1%) was ineffective. MDL appears effective in preventing the onset of disease in two mouse models of IDDM.

Electromyographic response of peroneal muscles in surgical and nonsurgical injured ankles during sudden inversion

Because the peroneal muscles are thought to act as a safeguard against lateral ankle injury, it is important to study their function. This study was undertaken to electromyographically assess the latency between sudden unexpected ankle inversion and the start of peroneal muscle activity. Three groups participated in the study, including subjects with lateral ankle sprain rehabilitated nonsurgically (N = 7), sprains rehabilitated following surgery (N = 6), and injury-free ankles (N = 11). Peroneal latency was assessed by dropping the subjects into inversion from a special platform. The platform was designed so that either ankle could be inverted to 35 degrees without warning. The ANOVA revealed no significant latency differences (p > .05) between the three groups. The study suggests that bilateral peroneal latency is unaffected by injury. Although it has been thought that healthy muscles provide a defense against ankle sprain, their latency is not permanently affected by ankle injury or by surgery performed to correct defects from injury. It appears that mechanoreceptor impairment may be rehabilitated and that it is not a factor in ankle injury.

Hepatic focal nodular hyperplasia: findings with color Doppler sonography

Color Doppler sonographic images of five patients with a total of six lesions of FNH were reviewed. All cases were confirmed pathologically. All six lesions showed increased intralesional flow in comparison to surrounding liver parenchyma on color Doppler sonography. Four of the six lesions showed significant peripheral flow; two of the six lesions showed central flow radiating peripherally from a central vessel. We conclude that increased color Doppler flow may be a characteristic feature of FNH. Increased internal flow has also been reported in HCC and hepatic metastatic disease. Considerable overlap is seen in color Doppler flow patterns. However, in patients clinically at low risk for malignancy, detection of a liver mass with increased color Doppler flow should suggest the diagnosis of FNH.

MDL 29311. Antioxidant with marked lipid- and glucose-lowering activity in diabetic rats and mice

MDL 29311, an analogue of probucol, administered to rats as a 1% dietary admixture for 2 wk before and 5 days after intravenous injection of 40 mg/kg of ALX significantly (P < 0.05) reduced plasma glucose (6.9 +/- 0.3 vs. 19.2 +/- 1.3 mM) and serum triglyceride (0.17 +/- 0.01 vs. 1.82 +/- 0.39 mM) levels in overnight-fasted ALX-plus-MDL 29311-administered rats vs. ALX-administered rats. A cross-over study indicated that MDL 29311 did not attenuate the diabetogenic action of ALX, but rather, directly lowered glucose and triglycerides. In rats injected intravenously with 45, 65, or 85 mg/kg of STZ and then administered control or MDL 29311 diet for 7 days, MDL 29311 decreased fasted plasma glucose to nondiabetic levels, decreased fasted and nonfasted plasma triglycerides by 49-79%, but did not affect plasma insulin levels. In STZ-induced (65 mg/kg) diabetic rats, MDL 29311 attenuated the increase in plasma nonesterified fatty acids during an 18-h fast; had little or no effect on glucagon, pyruvate, lactate, beta-hydroxybutyrate, acetoacetate, or cholesterol; and did not induce hypoglycemia in rats fasted up to 64 h. In nonfasted hyperinsulinemic db/db mice treated for 10 wk, MDL 29311 significantly lowered glucose levels by 14-40%, triglyceride levels by 31-63% and GHb from 8.0 to 5.4%, and had no consistent effect on plasma insulin levels. Because of its marked glucose- and lipid-lowering activity in both nonfasted hyperinsulinemic and fasted insulinopenic animals, MDL 29311 merits additional investigation as a potential antidiabetic agent.

Familial omphalocele: considerations in genetic counseling

Nonsyndromal omphalocele is generally regarded as a sporadic malformation. Recurrence risk is considered negligible. We report on a patient in whom 5 consecutive pregnancies (by 2 separate nonconsanguineous partners) were complicated by omphalocele as an isolated defect. Neither the patient nor her partners had history of relatives with omphalocele, although the patient's brother and his son had large umbilical hernias requiring repair in infancy. Some familial cases of nonsyndromal omphalocele have been previously reported; most such pedigrees suggest vertical transmission, although there are a few cases with only a single generation involved. In our case, the multigenerational finding of ventral wall hernias makes an autosomal dominant mechanism with variable expressivity a tenable explanation. The collected instances of familial nonsyndromal omphalocele emphasize omphalocele heterogeneity and caution in counseling recurrence risks.

Budd-Chiari syndrome: detection with color Doppler sonography

The value of color Doppler sonography in evaluating newly diagnosed Budd-Chiari syndrome in five patients was studied. Hepatic venous findings included absence of vessels (one patient), flow reversal (two patients), narrowing (four patients), and tortuosity (three patients). Detected collaterals included hepatic venous to hepatic venous (four patients), hepatic venous to subcapsular systemic venous (two patients), and portosystemic (three patients). Hepatic venous spectral Doppler waveforms were flat and essentially aphasic in four patients, indicative of distal hepatic venous compression. The inferior vena cava was markedly compressed in two patients and slightly compressed in one. Color Doppler sonography allowed more reliable and confident identification of irregular, compressed, or otherwise abnormal hepatic veins than did conventional sonography. Color Doppler sonography also showed collateral vessels that were undetected with conventional sonography or other imaging techniques. Our results suggest that color Doppler sonography may be a valuable tool in the initial diagnosis and evaluation of suspected Budd-Chiari syndrome.

Uncomplicated amebic liver abscess: prospective evaluation of percutaneous therapeutic aspiration

The performance of therapeutic aspiration in the treatment of amebic liver abscess, advocated and practiced in many centers, is controversial. Previously, this practice has been evaluated in retrospective analyses. To test the potential benefit of therapeutic aspiration, the authors undertook a prospective randomized trial in 57 patients admitted for suspected amebic liver abscess during a 15-month period. Sixteen patients were excluded from the trial. The remaining 41 patients were randomly included in one of two study groups to receive amebicidal therapy alone or amebicidal therapy coupled with image-guided percutaneous therapeutic aspiration. All patients in the trial recovered. No statistically significant benefit was demonstrated in the aspiration group for the two objective parameters evaluated: length of hospitalization and duration of time to becoming afebrile. Subjective improvement in symptoms after aspiration was greater in the aspiration group at a marginally statistically significant level. These data do not support the adjunctive performance of percutaneous therapeutic aspiration in the treatment of uncomplicated amebic liver abscess. Amebicidals alone were equally efficacious in treating the group studied.