Small extracellular vesicle-loaded bevacizumab reduces the frequency of intravitreal injection required for diabetic retinopathy

Diabetic retinopathy (DR) is associated with retinal neovascularization, hard exudates, inflammation, oxidative stress and cell death, leading to vision loss. Anti-vascular endothelial growth factor (Anti-VEGF) therapy through repeated intravitreal injections is an established treatment for reducing VEGF levels in the retina for inhibiting neovascularization and leakage of hard exudates to prevent vision loss. Although anti-VEGF therapy has several clinical benefits, its monthly injection potentially causes devastating ocular complications, including trauma, intraocular hemorrhage, retinal detachment, endophthalmitis, etc. Methods: As mesenchymal stem cells (MSCs) and MSC-derived extracellular vesicles (MSC-EVs) demonstrated safety in clinical studies, we have tested the efficacy of MSC-derived small EVs (MSC-sEVs) loaded anti-VEGF drug bevacizumab in a rat model of DR. Results: The study identified a clinically significant finding that sEV loaded with bevacizumab reduces the frequency of intravitreal injection required for treating diabetic retinopathy. The sustained effect is observed from the reduced levels of VEGF, exudates and leukostasis for more than two months following intravitreal injection of sEV loaded with bevacizumab, while bevacizumab alone could maintain reduced levels for about one month. Furthermore, retinal cell death was consistently lower in this period than only bevacizumab. Conclusion: This study provided significant evidence for the prolonged benefits of sEVs as a drug delivery system. Also, EV-mediated drug delivery systems could be considered for clinical application of retinal diseases as they maintain vitreous clarity in the light path due to their composition being similar to cells.

Laparoscopic major hepatectomy: pure laparoscopic approach versus hand-assisted technique

Laparoscopic liver resections are being performed with increasing frequency, with several groups having reported minimally invasive approaches for major anatomic hepatic resections. Some surgeons favor a pure laparoscopic approach, while others prefer a hand-assisted approach for major laparoscopic liver resections. There are clear advantages and disadvantages to a hand-assisted technique. The purpose of this study is to summarize the literature comparing pure laparoscopic and hand-assisted approaches for minimally invasive hepatic resection, and to describe our approach in 432 laparoscopic liver resections.

Orthodontic uprighting of impacted mandibular permanent second molar: a case report

The mandibular second molars can become impacted beneath the crown of the first molars due to various causes and fail to erupt normally. Presented herewith is a case report of orthodontic uprighting of a mesioangular impacted mandibular right permanent second molar. Though various treatment options were available, an uprighting push spring appliance was used as it is easy to fabricate and produces distal tipping and uprighting of the impacted tooth without the necessity of surgical assistance, bone removal, or splinting. The uprighting of the mandibular second molar was achieved within two months.

Ubiquitination by the anaphase-promoting complex drives spindle checkpoint inactivation

Eukaryotic cells rely on a surveillance mechanism known as the spindle checkpoint to ensure accurate chromosome segregation. The spindle checkpoint prevents sister chromatids from separating until all kinetochores achieve bipolar attachments to the mitotic spindle. Checkpoint proteins tightly inhibit the anaphase-promoting complex (APC), a ubiquitin ligase required for chromosome segregation and progression to anaphase. Unattached kinetochores promote the binding of checkpoint proteins Mad2 and BubR1 to the APC-activator Cdc20, rendering it unable to activate APC. Once all kinetochores are properly attached, however, cells inactivate the checkpoint within minutes, allowing for the rapid and synchronous segregation of chromosomes. How cells switch from strong APC inhibition before kinetochore attachment to rapid APC activation once attachment is complete remains a mystery. Here we show that checkpoint inactivation is an energy-consuming process involving APC-dependent multi-ubiquitination. Multi-ubiquitination by APC leads to the dissociation of Mad2 and BubR1 from Cdc20, a process that is reversed by a Cdc20-directed de-ubiquitinating enzyme. The mutual regulation between checkpoint proteins and APC leaves the cell poised for rapid checkpoint inactivation and ensures that chromosome segregation promptly follows the completion of kinetochore attachment. In addition, our results suggest a mechanistic basis for how cancer cells can have a compromised spindle checkpoint without corresponding mutations in checkpoint genes.

The contralateral slip

Between July 1994 and June 2004, 60 patients with 76 slipped upper femoral epiphyses were managed within the adult trauma service of three hospitals. Treatment was by a single cannulated screw.

Of these cases, 53 were unilateral, in 17 of which uncomplicated prophylactic fixation of the contralateral hip was performed. Of the other 36 cases, nine presented with a subsequent slip despite ongoing out-patient care. The subsequent slip was unpredictable in timing and unrelated to the age at the initial slip. It was more often unstable and in one case avascular necrosis developed. The overall rate of avascular necrosis, although in accordance with the literature, was 60% in acute unstable slips with a slip angle greater than 40°.

In our experience, prophylactic fixation was safer than continued observation of the contralateral hip.

Chronic ethanol and nicotine interaction on rat tissue antioxidant defense system

Ethanol consumption and cigarette smoking are common in societies worldwide and have been identified as injurious to human health. This study was undertaken to examine the interactive effects of chronic ethanol and nicotine consumption on the antioxidant defense system in different tissues of rat. Male Fisher-344 rats were divided into four groups of five animals each and treated for 6.5 weeks as follows: (1) Control rats were administered normal saline orally; (2) ethanol (20% [wt./vol.]) was given orally at a dose of 2 g/kg; (3) nicotine was administered subcutaneously at a dose of 0.1 mg/kg; and (4) a combination of ethanol plus nicotine was administered by the route and at the dose described above. The animals were killed 20 h after the last treatment, and liver, lung, kidney, and testes were isolated and analyzed. Chronic ingestion of ethanol resulted in a significant depletion of glutathione (GSH) content in liver, lung, and testes, whereas chronic administration of nicotine significantly depleted GSH content in liver and testes. The combination of ethanol plus nicotine resulted in a significant depletion of GSH content in liver, lung, and testes. Ethanol, nicotine, or a combination of ethanol plus nicotine significantly increased superoxide dismutase (SOD) activity in liver and decreased SOD activity in kidney. Ethanol, nicotine, or a combination of ethanol plus nicotine significantly decreased catalase (CAT) activity in liver and increased CAT activity in kidney and testes. Chronic ingestion of ethanol resulted in a significant decrease in glutathione peroxidase (GSH-Px) activity in liver and kidney, whereas a combination of ethanol plus nicotine increased GSH-Px activity in liver and decreased GSH-Px activity in kidney and testes. Ethanol, nicotine, or a combination of ethanol plus nicotine significantly increased lipid peroxidation, respectively, in liver. It is suggested that prolonged exposure to ethanol and nicotine produce similar, and in some cases additive, oxidative tissue injuries in rat.

Eukaryotic-like adenylyl cyclases in Mycobacterium tuberculosis H37Rv: cloning and characterization

Screening the Mycobacterium tuberculosis H37Rv genomic library for complementation of catabolic defect for cAMP-dependent expression of maltose operon produced the adenylyl cyclase gene (Mtb cya, (1997)) annotated later as Rv1625c (Cole, S. T., Brosch, R., Parkhill, J., Garnier, T., Churcher, C., Harris, D., Gordon, S. V., Eiglmeier, K., Gas, S., Barry, C. E., III, et al. (1998) Nature 393, 537-544). The deduced amino acid (aa) sequence (443 aa) encoded by Mtb cya contains a single hydrophobic domain of six transmembrane helices (152 aa) in the amino-terminal half of the protein. Flanking this domain are an arginine-rich (17%) amino-terminal cytoplasmic tail (46 aa) and a carboxyl-terminal cytoplasmic domain (245 aa) with extensive homology to the catalytic core of eukaryotic adenylyl cyclases. Site-directed mutagenesis of Arg(43) and Arg(44) to alanine/glycine showed a loss of adenylyl cyclase activity, whereas mutagenesis to lysine restored the activity. Hence it is proposed that the formation of the catalytic site in Mtb adenylyl cyclase requires an interaction between Arg(43) and Arg(44) residues in the distal cytoplasmic tail and the carboxyl-terminal cytoplasmic domain. Mtb adenylyl cyclase activity at the physiological concentration of ATP (1 mm) was 475 nmol of cAMP/min/mg of membrane protein in the presence of Mn(2+) but only 10 nmol of cAMP/min/mg of membrane protein in the presence of Mg(2+). The physiological significance of the activation of Mtb adenylyl cyclase by Mn(2+) is discussed in view of the presence of manganese transporter protein in mycobacteria and macrophages wherein mycobacteria reside.

Autoantibodies to IA-2 and GAD65 in patients with type 2 diabetes mellitus of varied duration: prevalence and correlation with clinical features

OBJECTIVE

To determine the prevalence of autoantibodies to IA-2 (IA-2Ab) and glutamic acid decarboxylase (GADAb) in type 2 diabetes, their relationship to disease duration, and their importance in management decisions.

METHODS

We undertook a study of 101 patients with type 2 diabetes (defined as nonketotic hyperglycemia at diagnosis) of varied duration (median, 4 years). Results were compared with those from 36 patients with type 1 diabetes also of varied duration (median, 2 years). IA-2Ab and GADAb were measured by radioligand-binding assays with use of in vitro-synthesized, 35S-labeled antigens.

RESULTS

Of the 101 patients with type 2 diabetes, 20 (20%) were positive for GADAb; only 4 of these 20 were positive for IA-2Ab. In comparison, 75% of patients with type 1 diabetes were positive for GADAb, IA-2Ab, or both (P<0.0001). The coincidence of IA-2Ab positivity in GADAb-positive patients with type 2 diabetes was significantly lower than in patients with type 1 diabetes (20% versus 73%, respectively; P = 0.002). All four IA-2Ab- and GADAb-positive patients with type 2 diabetes required insulin and were younger than those positive for GADAb alone (P = 0.018). GADAb positivity in patients with type 2 diabetes was highly associated with insulin requirement (P = 0.004), with an odds ratio of 5.8 in predicting insulin dependence. Among patients with type 2 diabetes receiving insulin therapy, disease duration was significantly shorter (P = 0.025) and body mass index was significantly lower (P<0.001) in GADAb-positive versus GADAb-negative patients. In contrast to type 1 diabetes, in which GADAb values were negatively correlated with disease duration (r = -0.34; P = 0.044), no significant correlation with disease duration was observed in type 2 diabetes (r = -0.166; P = 0.48).

CONCLUSION

Irrespective of duration of disease, measurement of IA-2Ab and GADAb can help to identify those patients with type 2 diabetes most likely to require insulin therapy.

Breakthrough pain in cancer patients: new therapeutic approaches to an old challenge

Breakthrough pain is a well recognized but ill-defined phenomenon that occurs commonly in the presence of otherwise stable, persistent pain. It is defined now as a "transient pain episode that occurs, or breaks through from the otherwise stable background pain." Breakthrough pain is usually associated with moderate to severe pain and may form a predictor of poor response to treatment with routine pharmacotherapy. Breakthrough pain is also associated with functional impairment and psychological distress. The assessment and treatment should be multidimensional. Although primary therapies such as chemotherapy, radiation treatment, and surgical options are explored, the mainstay of treatment is pharmacotherapy. Nonpharmacologic methods, such as orthotic devices and joint stabilizations along with behavioral methods, should be explored. Anesthetic and neurosurgical procedures are performed on a limited number of patients based on the prognosis, intractable nature of pain, and favorable risk/benefit ratio. Newer oral transmucosal fentanyl offers a favorable pharmacokinetic and pharmacodynamic profile and ease of administration.

The utility of urgent colonoscopy in the evaluation of acute lower gastrointestinal tract bleeding: a 2-year experience from a single center

OBJECTIVE

Urgent colonoscopy is often recommended to evaluate acute rectal bleeding. However, it may not identify a source because of blood in the lumen or inadequate preparation. Our aim was to determine the utility of urgent colonoscopy as the initial test for acute rectal bleeding.

METHODS

This was a retrospective chart review of all patients discharged in 1997 and 1998 with an International Classification of Diseases, 9th Revision, code for hematochezia or rectal bleeding.

RESULTS

We identified 514 charts but excluded 424 because of inaccurate coding. In the 90 with confirmed acute rectal bleeding, colonoscopy was the initial test in 39; age, sex, and race distributions were similar to those who did not have colonoscopy. A definite source of bleeding was seen at colonoscopy in only three patients, a probable source in 26, and no source in 10. Therapeutic intervention in four patients with a definite or probable source was successful in three. The commonest reasons for not performing urgent colonoscopy were bleeding from presumed hemorrhoids or bleeding that was clinically insignificant. Spontaneous resolution of bleeding and length of hospital stay were not affected by urgent colonoscopy. Five patients had surgery for unrelated reasons. In-hospital mortality was 2% and was unrelated to bleeding.

CONCLUSION

Urgent colonoscopy as the initial investigation in acute lower GI tract bleeding probably does not alter the outcome in most cases. Identification of a definite bleeding source leading to successful therapeutic intervention is rare. Spontaneous resolution is frequent, length of hospital stay is similar, and clinical outcome is excellent regardless of whether or not urgent colonoscopy is performed.

Oxygen consumption and respiration following two yoga relaxation techniques

The present study was conducted to evaluate a statement in ancient yoga texts that suggests that a combination of both "calming" and "stimulating" measures may be especially helpful in reaching a state of mental equilibrium. Two yoga practices, one combining "calming and stimulating" measures (cyclic meditation) and the other, a "calming" technique (shavasan), were compared. The oxygen consumption, breath rate, and breath volume of 40 male volunteers (group mean +/- SD, 27.0 +/- 5.7 years) were assessed before and after sessions of cyclic meditation (CM) and before and after sessions of shavasan (SH). The 2 sessions (CM, SH) were 1 day apart. Cyclic meditation includes the practice of yoga postures interspersed with periods of supine relaxation. During SH the subject lies in a supine position throughout the practice. There was a significant decrease in the amount of oxygen consumed and in breath rate and an increase in breath volume after both types of sessions (2-factor ANOVA, paired t test). However, the magnitude of change on all 3 measures was greater after CM: (1) Oxygen consumption decreased 32.1% after CM compared with 10.1% after SH; (2) breath rate decreased 18.0% after CM and 15.2% after SH; and (3) breath volume increased 28.8% after CM and 15.9% after SH. These results support the idea that a combination of yoga postures interspersed with relaxation reduces arousal more than relaxation alone does.

Opioid and Nonopioid Therapy in Cancer Pain: The Traditional and the New

Management of cancer pain has made sidnificant progress in recent years, partly due to the Agency for Health Care Policy and Research (AHCPR) guidelines, but mostly it seems to be due to the death and dying movement in the world. However, cancer pain on occasion poses significant problems and needs accurate diganosis and appropriate intervention. Pharmacotherapy remains the mainstay of treating cancer pain. Most cancer pain syndromes present with moderate to severe pain, associated with several comorbid problems necessitating the multidisciplinary approach to optimally treat it. The psychologic factors associated wth serious illness, terminal prognoses, and dying complicate the scenario even more as compared with that of nonmalignant pain. Although such patients are entitled to more aggressive analgesic therapy, it is unfortunate that this is not achieved in a significant percentage of cases. In this review, we address some of the above issues and attempt to summarize the traditional pharmacologic therapies highlighting their modern modes of implementation in cancer pain management. Special emphasis on the state-of-the art innovations in this field wil be noted.

Neural blockade for abdominopelvic pain of oncologic origin

Neural blockade, like other accepted treatments for persistent pain, is not a panacea. Careful assessment is required to elicit the need for complementary interventions, including pharmacological management and psychobehavioral and rehabilitative approaches, combined with attention to the palliation of other symptoms. Celiac and superior hypogastric plexus blocks are well-accepted, effective, and minimally hazardous means for providing palliation of visceral abdominopelvic pain. Although they require radiological imaging, they are relatively undemanding of the experienced anesthesiologist pain specialist and do not deplete patients' limited resources and energy. Because of their uniquely favorable risk:benefit ratio, these procedures should be considered early in the course of treating patients with abdominopelvic pain that is expected to persist.

Effect of yoga training on maze learning

The performance in a maze learning task was assessed in adults of either sex (n = 31) before and after 30 days of yoga training and in an age and gender matched control group of subjects who did not receive training in yoga. Subjects were blind folded and used the dominant hand to trace the path in a wooden pencil maze. At each assessment, subjects were given 5 trials, without a gap between them. Performance was based on the time taken to complete the maze and the number of blind alleys taken. The time and error scores of Trial 1 were significantly less after yoga (two-factor ANOVA, Tukey test). Repeating trials significantly decreased time scores at Trial 5 versus Trial 1, for both groups on Day 1 and for the control group on Day 30. Hence the yoga group showed improved performance in maze tracing at retest 30 days later, which may be related to this group being faster learners and also the effect of yoga itself. Yoga training did not influence maze learning, based on the performance in 5 repeat trials.

Dose response of ethanol ingestion on antioxidant defense system in rat brain subcellular fractions

This study investigated the response of the antioxidant defense system in brain subcellular fractions after oral graded doses of ethanol to rat. Four groups of male Fischer-344 rats were orally administered saline, ethanol 2 g, 4 g, and 6 g/kg, respectively, and sacrificed 1 hour post treatment. Brain cytosol, synaptosomes, microsomes and mitochondria were separated by density gradient differential centrifugation and assayed for antioxidant system. A significant and dose-dependent-decrease in superoxide dismutase (SOD) activity was observed in all brain subcellular fractions. Catalase (CAT) activity was significantly decreased in brain mitochondria (67% and 80% of control) at higher doses of ethanol; whereas, CAT activity was significantly increased in cytosol, synaptosomes and microsomes. Glutathione peroxidase (GSH-Px) activity was significantly increased in all brain subcellular fractions except in cytosol at higher dose of ethanol. Malondialdehyde (MDA) content was significantly increased in all brain subcellular fractions showing dose response of ethanol-induced oxidative stress. The increase in MDA levels in the brain synaptosomes and microsomes were higher at 6 g dose of ethanol (155% and 163% of control) when compared to mitochondria and cytosol. Glutathione (GSH) levels were significantly increased in brain cytosol and microsomes at higher dose of ethanol (164% and 159% of control); whereas, the GSH concentration was significantly decreased in brain synaptosomes and mitochondria. The antioxidant enzyme (AOE) activity ratios (GSH-Px/SOD and GSH-Px + CAT/SOD) were dose dependently increased in all brain subcellular fractions, particularly in synaptosomes. The GSH/GSSG ratio was dose dependently increased in brain microsomes. The perturbations in the antioxidant defense system and enhanced lipid peroxidation following graded doses of ethanol ingestion indicate a dose-dependent-oxidative 2133stress response in brain subcellular compartments of rats.

Pain and loss of function in head and neck cancer survivors

Head and neck cancers are relatively uncommon malignancies and the characteristics of pain and functional impairments in survivors are not well studied. To characterize the incidence, location, severity, types and causes of pain; associated functional impairments, and pain management methods, the medical charts of 40 consecutive outpatients with biopsy-proven head and neck cancers were reviewed. Pain was severe in 52% (N = 21), and was located near sites of tumor origin. Pain was caused by tumor recurrence in 35% (N = 14), treatment sequelae in 30% (N = 12), multiple etiologies in 25% (N = 10), and unrelated causes in 10% (N = 4). Pains were mixed nociceptive and neuropathic pain in 37.5% (N = 15), nociceptive pain in 32.5% (N = 13), myofascial in 13.0% (N = 6), neuropathic in 7.5% (N = 3); and other mixed types in 7.5% (N = 3). Despite the high prevalence of dysphagia (82%), 60% used orally administered opioid-nonopioid analgesics. Physical disfigurement (87.5%; N = 35), dysphagia (62.5%, N = 25), and jaw dysfunction (40.0%; N = 16) were the most frequent physical impairments. Multiple regression analysis showed that the presence of skull base or mandibular bone involvement had significant influence on the severity of pain (P = 0.03, adjusted R2 0.25) We conclude that pain in head and neck cancer can be chronic, severe, and persistent despite completion of oncologic treatment.

Identification of profilin and src homology 3 domains as binding partners for Drosophila enabled

Drosophila Enabled (Ena) was first identified as a genetic suppressor of mutations in the Abelson tyrosine kinase and subsequently was shown to be a member of the Ena/vasodilator-stimulated phosphoprotein family of proteins. All members of this family have a conserved domain organization, bind the focal adhesion protein zyxin, and localize to focal adhesions and stress fibers. Members of this family are thought to be involved in the regulation of cytoskeleton dynamics. The Ena protein sequence has multiple poly-(L-proline) residues with similarity to both profilin and src homology 3 binding sites. Here, we show that Ena can bind directly to the Drosophila homolog of profilin, chickadee. Furthermore, Ena and profilin were colocalized in spreading cultured cells. We report that the proline-rich region of Ena is responsible for this interaction as well as for mediating binding to the src homology 3 domain of the Abelson tyrosine kinase. These data support the hypothesis that Ena provides a regulated link between signal transduction and cytoskeleton assembly in the developing Drosophila embryo.

Mutations in Drosophila enabled and rescue by human vasodilator-stimulated phosphoprotein (VASP) indicate important functional roles for Ena/VASP homology domain 1 (EVH1) and EVH2 domains

Drosophila Enabled (Ena) was initially identified as a dominant genetic suppressor of mutations in the Abelson tyrosine kinase and, more recently, as a member of the Ena/human vasodilator-stimulated phosphoprotein (VASP) family of proteins. We have used genetic, biochemical, and cell biological approaches to demonstrate the functional relationship between Ena and human VASP. In addition, we have defined the roles of Ena domains identified as essential for its activity in vivo. We have demonstrated that VASP rescues the embryonic lethality associated with loss of Ena function in Drosophila and have shown that Ena, like VASP, is associated with actin filaments and focal adhesions when expressed in cultured cells. To define sequences that are central to Ena function, we have characterized the molecular lesions present in two lethal ena mutant alleles that affected the Ena/VASP homology domain 1 (EVH1) and EVH2. A missense mutation that resulted in an amino acid substitution in the EVH1 domain eliminated in vitro binding of Ena to the cytoskeletal protein zyxin, a previously reported binding partner of VASP. A nonsense mutation that resulted in a C-terminally truncated Ena protein lacking the EVH2 domain failed to form multimeric complexes and exhibited reduced binding to zyxin and the Abelson Src homology 3 domain. Our analysis demonstrates that Ena and VASP are functionally homologous and defines the conserved EVH1 and EVH2 domains as central to the physiological activity of Ena.

Antigen-specific lymphoproliferative responses to tetanus toxoid: a means for the evaluation of Marek's disease virus-induced immunosuppression in chickens

Antigen-specific lymphoproliferative responses were examined in chickens following immunization with tetanus toxoid (Ttx). The immune competence of chickens was assessed by mitogen assay utilizing phytohemagglutinin (PHA)-stimulation and Ttx-specific antigen proliferation assay (Ttx-APA). Immune spleen cells but not peripheral blood leucocytes demonstrated specific proliferation following stimulation in vitro in a Ttx-APA. In this study, we examined firstly the effects of Marek's disease (MD)-associated immunosuppression on specific immune responses. The humoral and cell-mediated immune responses were monitored by enzyme-linked immunosorbent assay (ELISA) and Ttx-APA, respectively. Secondly, we examined if vaccination against MD using a conventional herpesvirus of turkeys (HVT) vaccine and two recombinant HVT (rHVT) vaccines would affect the development of Ttx-specific immune responses. The rHVT vaccines used in this study included two constructs: one expressing both Newcastle disease virus (NDV) and MD virus (MDV) genes (HVT/NDV/MDV), and another expressing only MDV genes (HVT/MDV). The mitogenic responses of spleen cells of the vaccinated chickens were inconsistent allowing no definitive conclusions about vaccinal immunosuppression. The results of the Ttx-APA indicated that Ttx-specific lymphoproliferative responses provide a meaningful measure of immunosuppression. The MDV-induced immunosuppression resulted in the inhibition of Ttx-specific lymphoproliferation in vitro. Both HVT and rHVT vaccines were not immunosuppressive as indicated by the development of normal Ttx-specific lymphoproliferative responses in chickens. These results indicate that vaccination against MD results not only in the prevention of tumor formation but also protection from possible virus-induced immunosuppression.

Nitric oxide inducing factor as a measure of antigen and mitogen-specific T cell responses in chickens

We describe here an assay to measure responses of T cells to in vitro stimulation with antigens and a T cell mitogen (ConA). Spleen cells from chickens immunized with live viruses and an inactivated antigen produced macrophage activating factors (MAF) in response to in vitro stimulation with homologous antigens. The production of MAF, quantitated by the induction of NO in a retrovirus transformed macrophage cell line, HD11 (Beug et al., 1979, Cell 18, 375) was antigen-specific and correlated well with T cell proliferation. Further studies showed that production of MAF was abrogated by cyclosporin A, anti-CD4 and anti-CD8 monoclonal antibodies. These data suggested that production of MAF required T cell activation and can be used as measure of antigen and mitogen-specific T cell responses in chickens.

Protective efficacy of a recombinant herpesvirus of turkeys as an in ovo vaccine against Newcastle and Marek's diseases in specific-pathogen-free chickens

We investigated the potential of a herpesvirus of turkey (HVT)-based recombinant virus (rHVT) as an in ovo vaccine to protect specific-pathogen-free chickens against Newcastle disease (ND) and Marek's disease (MD). The rHVT, designed to express fusion (F) and hemagglutinin-neuraminidase (HN) glycoproteins of the lentogenic Hitchner B1 strain of ND virus (NDV), as well as glycoproteins A and B of the GA strain of serotype 1 MD virus (MDV) was efficacious in protecting chickens against ND and MD. No adverse effects on hatchability or the survival of chickens were observed following in ovo vaccination with rHVT. A single administration at embryonation day 18 (ED18) or at hatch protected chickens against challenge-exposures with virulent MDV strain RB-1B and velogenic NDV strain GB-Texas (NDV-GB-TX). Vaccinated chickens developed antibodies against both viruses as detected by serological tests, namely, hemagglutination inhibition, virus neutralization and western immunoblotting for NDV, and immunofluorescence and radioimmunoprecipitation assays for MDV. PCR analysis showed that in ovo vaccination with rHVT resulted in a persistent infection leading to systemic immunity against ND for up to 8 weeks of age, the longest period of time tested in this study. However, virus isolation tests indicated that rHVT-vaccinated chickens were only partially protected from the replication of NDV-GB-TX in the trachea. The results of the study indicate that rHVT is safe for both ED18 and posthatch vaccination for ND and MD, and because the vaccine persists, it may induce longer lasting immunity than conventional live NDV vaccines.

Medical decision-making in a patient with a history of cancer and chronic non-malignant pain

The selection of cancer pain treatment modalities depends on careful assessment to establish the pathophysiology of the pain complaint. Treatment may consist of a single modality--e.g., pharmacotherapy--or multiple modalities--e.g., pharmacotherapy, anesthetic intervention, and radiotherapy for bone pain. Cancer patients may present with pain and multiple concomitant medical problems related to their primary neoplastic disease, complications of cancer treatment, or unrelated conditions including preexisting pain of nonmalignant origin. We present the case of a patient with new onset of pain superimposed on chronic nonmalignant pain. This case emphasizes the need for careful assessment and the close cooperation required between the pain consultant and the referring oncology staff to make optimal treatment decisions in the context of a complex medical illness.

Subarachnoid neurolytic block under general anesthesia in a 3-year-old with neuroblastoma

CASE REPORT

A 3-year-old boy with neuroblastoma complained of severe pain in the left lower extremity. Pharmacologic management had previously been attempted, but severe pain continued, and further upward titration was complicated by sedative effects.

METHODS AND RESULTS

Because the focus of treatment had become the controlling of pain, a lumbosacral subarachnoid neurolytic block was performed under general anesthesia. One-time neurolysis was more acceptable to the family than a procedure like epidural analgesia, that requires greater management. Contrast medium was used to monitor the spread of the neurolytic. An epidural catheter was inserted during the neurolytic block procedure for possible future use. The short-term results were good--pain reports and opioid doses decreased greatly, although with increased incontinence. The boy had new abdominal distention and pain 5 days after neurolysis. Opioid doses and sedatives were increased. He died 3 days later.

Chiropractic management of primary nocturnal enuresis

OBJECTIVE

To evaluate chiropractic management of primary nocturnal enuresis in children.

DESIGN

A controlled clinical trial for 10 wk preceded by and followed by a 2-wk nontreatment period.

SETTING

Chiropractic clinic of the Palmer Institute of Graduate Studies and Research.

PARTICIPANTS

Forty-six nocturnal enuretic children (31 treatment and 15 control group), from a group of 57 children initially included in the study, participated in the trial.

INTERVENTION

High velocity, short lever adjustments of the spine consistent with the Palmer Package Techniques; or a sham adjustment using an Activator at a nontension setting administered to the examiner's underlying contact point. Two 5th-year chiropractic students under the supervision of two clinic faculty performed the adjustments.

MAIN OUTCOME MEASURES

Frequency of wet nights.

RESULTS

The post-treatment mean wet night frequency of 7.6 nights/2 wk for the treatment group was significantly less than its baseline mean wet night frequency of 9.1 nights/2 wk (p = 0.05). For the control group, there was practically no change (12.1 to 12.2 nights/2 wk) in the mean wet night frequency from the baseline to the post-treatment. The mean pre- to post-treatment change in the wet night frequency for the treatment group compared with the control group did not reach statistical significance (p = 0.067). Twenty-five percent of the treatment-group children had 50% or more reduction in the wet night frequency from baseline to post-treatment while none among the control group had such reduction.

CONCLUSIONS

Results of the present study strongly suggest the effectiveness of chiropractic treatment for primary nocturnal enuresis. A larger study of longer duration with a 6-month follow-up is therefore warranted.

Interaction of avian reovirus with chicken lymphoblastoid cell lines

Four chicken lymphoblastoid cell lines were inoculated with avian reovirus strain S1133 and two local isolates, 965 and 615. Of the inoculated cell lines, TLT, a B-cell line, was productively infected with the three viruses as demonstrated by immunofluorescence assay (IFA) and radioimmunoprecipitation assay. A comparative growth curve analysis of the three avian reoviruses was done at 37 degrees and 41 degrees C. Isolate 965 replicated to a higher titre at both temperatures while the replication of S1133 and 615 was found to be inhibited at 41 degrees C. IFA revealed that among the transformed T lymphoblastoid cells used in this study, only MDCC-RP1 was permissive to virus infection with isolate 965, and at 41 degrees C, but not 37 degrees C.

Amphibian allantoinase. Molecular cloning, tissue distribution, and functional expression

The chain of enzymes necessary to convert uric acid to its metabolic products urea and glyoxylic acid in vertebrates is truncated through the successive loss of allantoicase, allantoinase, and urate oxidase during phylogenetic evolution. Previous studies have assigned the localization of both urate oxidase and allantinase to the peroxisome in the amphibian liver. This study reports the cloning of a cDNA encoding bullfrog (Rana catesbeiana) allantoinase, an enzyme that converts allantoin to allantoic acid. The cDNA is 2112 base pairs in length containing a 1449-base pair open reading frame which corresponds to a 483-residue protein (53,296 Da). Structural analysis of the deduced protein suggested two potential transmembrane segments and the presence of a putative mitochondrial localization sequence in the amino terminus. Immunocytochemical analysis revealed that allantoinase is localized to mitochondria and not to peroxisomes. On Northern blotting, a single mRNA species was detected in the liver and kidney of frog but not in other tissues; this distribution was confirmed by immunoblotting. The hepatic- and renal-specific expression of allantoinase coincides with the distribution of urate oxidase in these tissues in the frog. The allantoinase expressed in Saccharomyces cerevisiae and in Spodoptera frugiperda (Sf9) insect cells exhibits catalytic activity and is antigenically identical to the native frog enzyme.

Flow cytometric analysis of the neutralizing immune response against infectious bursal disease virus using reticuloendotheliosis virus-transformed lymphoblastoid cell lines

Infectious bursal disease virus (IBDV) is a lymphotropic virus with cytocidal effect on B lymphocytes of the bursa of Fabricius. We investigated the susceptibility of clonal populations of reticuloendotheliosis virus-transformed chicken B lymphocytes of both spleen and bursal origin to IBDV infection. The infected cells were metabolically-labelled and the viral polypeptides were analyzed by immunoprecipitation using monoclonal antibodies (MAbs). Virus adsorption and the effects of neutralizing convalescent antisera and MAbs on virus attachment were studied using flow cytometry. The results of the study indicate firstly that the transformed B cells support virus replication and provide an efficient system for studying IBDV-lymphocyte interactions. Secondly, results obtained also showed that the most potent neutralizing antibodies may not be those involved in preventing the receptor-mediated viral attachment but rather those involved in the inhibition of downstream events such as virus penetration or uncoating.

Radioimmunoprecipitation of avian reovirus polypeptides using virus-specific IgM and IgG murine monoclonal and chicken polyclonal antibodies

A simple and improved procedure for radioimmunoprecipitation (RIPA) for the identification of major immunogenic proteins of avian reovirus using murine monoclonal and chicken polyclonal antibodies is described. Bacterial proteins (Staphylococcus aureus-Protein A or Streptococcus species-Protein G) commonly used in RIPA procedures lack reactivities with low avidity monoclonals belonging to immunoglobulin (Ig)G or IgM subtypes, as well as avian Ig. Hence we used an indirect approach utilizing species-specific anti-IgM, IgG or chicken Ig antibodies followed by the precipitation of the immune complexes using Protein A. This improved the sensitivity of the RIPA enabling the antigenic analysis of the major antigenic proteins of avian reovirus. The results indicated that the virus is highly immunogenic in the natural host, chicken than in mice. Furthermore, there exists a direct correlation between a strong neutralizing antibody response and an increased precipitation of the sigma (sigma) proteins of the virus. The results also demonstrate a strong association between the conformational viral epitopes of the three classes of proteins, large (lambda), medium (mu) and small (sigma).

Analysis of inter-serotypic structural relationships of infectious bursal disease virus using detergent solubilization and radioimmunoprecipitation with monoclonal antibodies

Monoclonal antibodies (MAbs) neutralizing only the infectious bursal disease virus strains (IBDV) belonging to serotype 1 also immunoprecipitated the heterologous major antigenic proteins of serotype 2 IBDV. Detergent-solubilization followed by radioimmunoprecipitation assays (RIPA) using the MAbs revealed structural similarities between the conformation-dependent antigenic determinants of IBDV of the two existing serotypes. The presence of non-ionic detergent Triton X-100 determined the binding of altered proteins by MAbs in RIPA.

Biological roles of the major capsid proteins and relationships between the two existing serotypes of infectious bursal disease virus

Neutralizing monoclonal antibodies (n-MAbs) were produced against infectious bursal disease virus (IBDV) of serotypes 1 and 2. The n-MAbs recognizing the major antigenic proteins VP2 and VP3, were characterized using different strains of IBDV representing the existing two serotypes and a variant subtype of serotype 1. The biological properties of these viral antigens as defined by the MAbs in vitro, were studied utilizing post-adsorption virus neutralization tests and fluorescence-activated cell sorter analysis. The MAbs directed against the immunodominant epitopes on VP2 were capable of enhanced virus neutralization but did not inhibit the virus attachment to susceptible cells. These MAbs were able to neutralize the virus by interfering with an event subsequent to virus adsorption, possibly inhibiting virus penetration or uncoating. On the contrary, a MAb that immunoprecipitated the other capsid protein VP3 was able to prevent virus attachment although it possessed lower neutralization titers. Cross-immunoprecipitations of various virus strains by these MAbs and antisera revealed interrelationships between the two serotypes of IBDV.

Sudden death due to unsuspected coronary vasculitis

Coronary artery vasculitis is a well-recognized complication of polyarteritis nodosa and is occasionally seen in other forms of systemic vasculitis. However, involvement of the major epicardial coronary arteries leading to myocardial infarction and death is uncommon. Isolated coronary arteritis is even more rare. We report three cases of sudden death due to myocardial ischemia associated with arteritis of the major coronary arteries. All three decedents were previously healthy young to middle-aged men who had died suddenly after complaints of chest pain and shortness of breath. The autopsy findings and differential diagnoses are presented. Such cases are of particular interest to the medical examiner because of the sudden, unexpected nature of the deaths. An approach to the correct diagnosis is discussed.

Comparison of neutralizing antigens of recent isolates of infections bursal disease virus

Monoclonal antibodies (MAbs) to a local turkey isolate (QT-1) of infectious bursal disease virus (IBDV) were produced to identify the virus-specific neutralizing proteins. Radioimmunoprecipitation assays showed that all the MAbs were specific for major viral protein, VP2. Two of the MAbs neutralized the local turkey and chicken isolates along with a reference strain belonging to serotype 1 but not the reference strain of serotype 2. The reactivities of the neutralizing MAbs against two reference strains and some recent field strains of IBDV isolated in the province of Québec were studied by indirect enzyme-linked immunosorbent assay and virus neutralization tests. The variations in the reactivities of the MAbs observed suggest differences in the neutralizing epitopes of the different isolates. Competitive binding assay using the MAbs revealed the presence of a third epitope involved in the neutralization of IBDV belonging to serotype 1.

Effects of the Taser in fatalities involving police confrontation

Sixteen deaths associated with the use of the Taser were examined. All involved young males who had a history of abuse of controlled substances; all but three were under the influence of cocaine, phencyclidine [phenylcyclohexylpiperidine (PCP)], or amphetamine. All were behaving in a bizarre or unusual fashion which necessitated calling the police. The cause of death was an overdose of drugs in eleven, gunshot wounds in three, heart disease and Taser shock in one, and an undetermined cause in one. All were considered to be under the influence of PCP by the police at the time of the incident. All were unarmed, which was the reason a Taser was used instead of a more lethal weapon. The conclusion reached after evaluation of these cases is that the Taser in and of itself does not cause death, although it may have contributed to death in one case.

Isolation of infectious bursal disease virus from turkeys with arthritic and respiratory symptoms in commercial farms in Quebec

Infectious bursal disease viruses (IBDVs) were isolated from turkeys showing symptoms of arthritis and respiratory disease in commercial poultry farms in the province of Quebec, Canada. Synovial fluids collected from hock joints of arthritic birds and peripheral blood leukocytes obtained from the birds with respiratory problems were used for virus isolation in embryonated chicken eggs, and Vero and BGM-70 cell cultures. The infected cells were evaluated for the presence of IBDV by indirect immunofluorescence assay using monoclonal antibodies. The viruses were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of viral genome and by electron microscopy. Although one of these turkey isolates tested was neutralized by serotype 1-specific commercial chicken antisera, preliminary results indicated that there are antigenic differences between the Quebec isolate, IBDV QT-1, and the existing strains of IBDV belonging to serotype 1.

Rhabdomyolysis following violent behavior and coma

An individual suspected of being under the influence of phencyclidine (PCP) exhibited acute psychotic and violent behavior which was followed by cardiac arrest, coma, and renal failure. Sections of the damaged muscle showed rhabdomyolysis, and sections of the kidneys showed myoglonin casts positive for immunoperoxidase stain. Extensive toxicology studies for narcotics, PCP, and cocaine were negative. Therefore, a correlation between PCP and rhabdomyolysis associated with acute psychotic and violent behavior could not be made with certainty. The etiology and pathogenesis of rhabdomyolysis are discussed in depth.

A Factorial Evaluation of Effects of Model Specification and Error on Parameter Estimation in a Structural Equation Model

In an experiment manipulating artificial data in a factorial design, model misspecification and varying levels of error in measurement and in model structure are shown to have significant effects on LISREL parameter estimates in a modified peer influence model (Duncan, Haller & Portes, 1971). The extent of error present in both the measurement and the model have significant direct effects on estimated parameter values, and the two sorts of error interact as well. In specification, incorrect omission of parameters seems to have more impact on parameter error than does incorrect inclusion of parameters.

Are Semantic Response Scales Equivalent?

Three frequently used response formats -- Likert, semantic-differential and single anchor (Stapel) -- are compared via analysis of covariance structures. The cumulative results based on four data sets provided evidence inconsistent with previous research suggesting that these formats are interchangeable. Consistently across studies, the semantic-differential format is most preferred while in most cases the Stapel format is least preferred.

Hierarchical Models of Attitude

Although the philosophy of science literature argues that a distinction should be made between different levels of abstraction, it is only recently that such models have been developed and estimated by researchers in the social sciences. Estimation of such hierarchical models, which was not possible earlier, is made easier by the work of Bentler and Weeks (1979) and Joreskog and Sorbom (1981). This paper illustrates the application and use of hierarchical models using the structure of attitude as an example. Hierarchical models of attitude showed considerably better fit and interpretable results than the non-hierarchical model. Such models also appear to be a better way to conceptualize and estimate models in the presence of collinear constructs. Caution should be exercised, however, as higher-order models may not be uniquely determined.

Cyclic alternating combination chemotherapy for small cell lung cancer

Sixty-two patients with small cell carcinoma of lung received cyclic alternating non-cross-resistant combination chemotherapy. Radiation to the chest was given to all the patients. Patients were given a course of VP16, adriamycin and vincristine (VAV) followed by radiation (3,000 rads) to the chest and then a second course of VAV. Three weeks later, a course of cytoxan, CCNU, and methotrexate (CCM) was given (6 weeks). Subsequently, the treatment was cycled between two courses of VAV (6 weeks) and one course of CCM (6 weeks). Overall objective response rate of 73%, with 45% complete response, was noted. Overall median survival was 50 weeks, with 83 weeks for complete responders. Median survival for patients with regional disease was 58 weeks compared to 40 weeks for extensive disease. All the patients headed for complete response did so prior to receiving CCM. These results were not superior to conventional combination chemotherapy regimens.