Evaluation of the Central Effects of Systemic Lentiviral-Mediated Leptin Delivery in Streptozotocin-Induced Diabetic Rats

Type 1 diabetes (T1D) is characterized by hyperphagia, hyperglycemia and activation of the hypothalamic-pituitary-adrenal (HPA) axis. We have reported previously that daily leptin injections help to alleviate these symptoms. Therefore, we hypothesized that leptin gene therapy could help to normalize the neuroendocrine dysfunction seen in T1D. Adult male Sprague Dawley rats were injected i.v. with a lentiviral vector containing the leptin gene or green fluorescent protein. Ten days later, they were injected with the vehicle or streptozotocin (STZ). HPA function was assessed by measuring norepinephrine (NE) levels in the paraventricular nucleus (PVN) and serum corticosterone (CS). Treatment with the leptin lentiviral vector (Lepvv) increased leptin and insulin levels in non-diabetic rats, but not in diabetic animals. There was a significant reduction in blood glucose levels in diabetic rats due to Lepvv treatment. Both NE levels in the PVN and serum CS were reduced in diabetic rats treated with Lepvv. Results from this study provide evidence that leptin gene therapy in STZ-induced diabetic rats was able to partially normalize some of the neuroendocrine abnormalities, but studies with higher doses of the Lepvv are needed to develop this into a viable option for treating T1D.

Effects of Dietary β-Carotene on the Melanization Response and Growth Rate of Trichoplusia ni (Lepidoptera: Noctuidae)

Animals rely on carotenoids as fundamental precursors for hormones and antioxidants, and animals must acquire carotenoids from their diet. Previous research has shown that insects often absorb carotenoids in amounts proportional to those in their diet, and that carotenoids play key roles in multitrophic interactions. The consumption of diets that provide high levels of antioxidant compounds is associated with high levels of immune responses; however, it is unknown whether individual carotenoids directly influence immune response. Here, the objective of this study was to examine the effect of the carotenoid β-carotene on melanization, a measure of immune response, and growth rate of Trichoplusia ni Hübner (Lepidoptera: Noctuidae). To fulfill the objective, a low, medium, and high concentration of β-carotene, representing the range found in typical host plants, were mixed in an artificial diet, and immune response and growth rate were assessed in fifth instar larvae. Immune response was induced by injection of chromatography beads in to the abdomen of the larvae, and percent melanization was measured after injection. Melanization was greatest when larvae were reared on high β-carotene diets. Mass was measured at 5 and 10 d to assess growth rate. Larvae reared on high β-carotene diets initially gained little mass, but after 10 d larvae reared on no and high β-carotene diets were larger than those reared on other diets. This research has shown that β-carotene has the potential to influence the immune response and growth rate of T. ni.

K2P2.1 (TREK-1)-activator complexes reveal a cryptic selectivity filter binding site

Polymodal K_2P (KCNK) thermo- and mechanosensitive TREK¹ potassium channels, generate ‘leak’ currents that regulate neuronal excitability, respond to lipids, temperature, and mechanical stretch, and influence pain, temperature perception, and anesthetic responses^1–3. These dimeric voltage-gated ion channel (VGIC) superfamily members have a unique topology comprising two pore forming regions per subunit^4–6. Contrasting other potassium channels, K_2Ps use a selectivity filter ‘C-type’ gate^7–10 as the principal gating site. Despite recent advances^3,11,12, K_2Ps suffer from a poor pharmacologic profile limiting mechanistic and biological studies. Here, we describe a new small molecule TREK activator class that directly stimulates the C-type gate by acting as molecular wedges that restrict interdomain interface movement behind the selectivity filter. Structures of K_2P2.1(TREK-1) alone with two selective K_2P2.1(TREK-1) and K_2P10.1(TREK-2) activators, an N-aryl-sulfonamide, ML335, and a thiophene-carboxamide, ML402, define a cryptic binding pocket unlike other ion channel small molecule binding sites and, together with functional studies, identify a cation-π interaction that controls selectivity. Together, our data unveil a previously unknown, druggable K_2P site that stabilizes the C-type gate ‘leak mode’ and provide direct evidence for K_2P selectivity filter gating.

The significance of petroleum bitumen in ancient Egyptian mummies

Mummification was practised in ancient Egypt for more than 3000 years, emerging from initial observations of buried bodies preserved by natural desiccation. The use of organic balms (and other funerary practices) was a later introduction necessitated by more humid burial environments, especially tombs. The dark colour of many mummies led to the assumption that petroleum bitumen (or natural asphalt) was ubiquitous in mummification; however, this has been questioned for more than 100 years. We test this by investigating 91 materials comprising balms, tissues and textiles from 39 mummies dating from ca 3200 BC to AD 395. Targeted petroleum bitumen biomarker (steranes and hopanes) analyses by gas chromatography-mass spectrometry selected ion monitoring (GC-MS SIM, m/z 217 and 191) showed no detectable bitumen use before the New Kingdom (ca 1550-1070 BC). However, bitumen was used in 50% of New Kingdom to Late Period mummies, rising to 87% of Ptolemaic/Roman Period mummies. Quantitative determinations using (14)C analyses reveal that even at peak use balms were never more than 45% w/w bitumen. Critically, the dark colour of balms can be simulated by heating/ageing mixtures of fats, resins and beeswax known to be used in balms. The application of black/dark brown balms to bodies was deliberate after the New Kingdom reflecting changing funerary beliefs and shifts in religious ideology.This article is part of the themed issue 'Quantitative mass spectrometry'.

Tethered protein display identifies a novel Kir3.2 (GIRK2) regulator from protein scaffold libraries

Use of randomized peptide libraries to evolve molecules with new functions provides a means for developing novel regulators of protein activity. Despite the demonstrated power of such approaches for soluble targets, application of this strategy to membrane systems, such as ion channels, remains challenging. Here, we have combined libraries of a tethered protein scaffold with functional selection in yeast to develop a novel activator of the G-protein-coupled mammalian inwardly rectifying potassium channel Kir3.2 (GIRK2). We show that the novel regulator, denoted N5, increases Kir3.2 (GIRK2) basal activity by inhibiting clearance of the channel from the cellular surface rather than affecting the core biophysical properties of the channel. These studies establish the tethered protein display strategy as a means to create new channel modulators and highlight the power of approaches that couple randomized libraries with direct selections for functional effects. Our results further underscore the possibility for the development of modulators that influence channel function by altering cell surface expression densities rather than by direct action on channel biophysical parameters. The use of tethered library selection strategies coupled with functional selection bypasses the need for a purified target and is likely to be applicable to a range of membrane protein systems.

Effects of dried plum supplementation on bone metabolism in adult C57BL/6 male mice

Dietary supplementation of dried plum (DP) prevents bone loss and restores bone mass in osteopenic animal models. This study was designed to determine the effects of DP supplementation on bone metabolic activity over time using adult (6-month-old) male C57BL/6 mice (n = 40) receiving control (CON = AIN93 M) or CON+DP 25 % (w/w) diets for 4 or 12 weeks. After 4 weeks of treatment, animals consuming the DP diet had a higher whole-body bone mineral density, vertebral trabecular bone volume (BV/TV), and femoral cortical thickness compared to the CON animals. In the distal metaphysis of the femur, BV/TV was increased in the DP-treated animals, but only after 12 weeks. Bone histomorphometric analyses revealed that DP decreased osteoblast surface (67 %) and osteoclast surface (62 %) at 4 weeks, but these surfaces normalized to the CON animals by 12 weeks. Coincident with these changes, the mineralizing surface (MS/BS) and cancellous bone formation rate (BFR/BS) were reduced at 4 weeks in the DP group compared to the CON, but by 12 weeks of DP supplementation, BFR/BS (~twofold) and MS/BS (~1.7-fold) tended to be increased (p < 0.10). The relative abundance of RNA for key regulators of osteoblast and osteoclast differentiation and indicators of osteoblast activity were reduced in the DP group at 4 weeks with no difference between groups at 12 weeks. These results indicate that supplementing the diet with DP initially suppressed cancellous bone turnover, but a biphasic response occurs over time, resulting in a positive effect on bone mass and structure.

A high-throughput functional screen identifies small molecule regulators of temperature- and mechano-sensitive K2P channels

K_2P (KCNK) potassium channels generate “leak” potassium currents that strongly influence cellular excitability and contribute to pain, somatosensation, anesthesia, and mood. Despite their physiological importance, K_2Ps lack specific pharmacology. Addressing this issue has been complicated by the challenges that the leak nature of K_2P currents poses for electrophysiology-based high-throughput screening strategies. Here, we present a yeast-based high-throughput screening assay that avoids this problem. Using a simple growth-based functional readout, we screened a library of 106,281 small molecules and identified two new inhibitors and three new activators of the mammalian K_2P channel K_2P2.1 (KCNK2, TREK-1). By combining biophysical, structure–activity, and mechanistic analysis, we developed a dihydroacridine analogue, ML67-33, that acts as a low micromolar, selective activator of temperature- and mechano-sensitive K_2P channels. Biophysical studies show that ML67-33 reversibly increases channel currents by activating the extracellular selectivity filter-based C-type gate that forms the core gating apparatus on which a variety of diverse modulatory inputs converge. The new K_2P modulators presented here, together with the yeast-based assay, should enable both mechanistic and physiological studies of K_2P activity and facilitate the discovery and development of other K_2P small molecule modulators.

Metabolic and thermal stimuli control K(2P)2.1 (TREK-1) through modular sensory and gating domains

The two-pore domain potassium channel K_2P2.1 (TREK-1) responds to extracellular and intracellular stimuli, including pH and temperature. This study elucidates how the intracellular sensor element relays metabolic and thermal stimuli to the extracellular C-type gating element.

K_2P2.1 (TREK-1) is a polymodal two-pore domain leak potassium channel that responds to external pH, GPCR-mediated phosphorylation signals, and temperature through the action of distinct sensors within the channel. How the various intracellular and extracellular sensory elements control channel function remains unresolved. Here, we show that the K_2P2.1 (TREK-1) intracellular C-terminal tail (Ct), a major sensory element of the channel, perceives metabolic and thermal commands and relays them to the extracellular C-type gate through transmembrane helix M4 and pore helix 1. By decoupling Ct from the pore-forming core, we further demonstrate that Ct is the primary heat-sensing element of the channel, whereas, in contrast, the pore domain lacks robust temperature sensitivity. Together, our findings outline a mechanism for signal transduction within K_2P2.1 (TREK-1) in which there is a clear crosstalk between the C-type gate and intracellular Ct domain. In addition, our findings support the general notion of the existence of modular temperature-sensing domains in temperature-sensitive ion channels. This marked distinction between gating and sensory elements suggests a general design principle that may underlie the function of a variety of temperature-sensitive channels.

Variation in GIGYF2 is not associated with Parkinson disease

OBJECTIVE

A recent study reported that mutations in a gene on chromosome 2q36-37, GIGYF2, result in Parkinson disease (PD). We have previously reported linkage to this chromosomal region in a sample of multiplex PD families, with the strongest evidence of linkage obtained using the subset of the sample having the strongest family history of disease and meeting the strictest diagnostic criteria. We have tested whether mutations in GIGYF2 may account for the previously observed linkage finding.

METHODS

We sequenced the GIGYF2 coding region in 96 unrelated patients with PD used in our original study that contributed to the chromosome 2q36-37 linkage signal. Subsequently, we genotyped the entire sample of 566 multiplex PD kindreds as well as 1,447 controls to test whether variants in GIGYF2 are causative or increase susceptibility for PD.

RESULTS

We detected three novel variants as well as one of the previously reported seven variants in a total of five multiple PD families; however, there was no consistent evidence that these variants segregated with PD in these families. We also did not find a significant increase in risk for PD among those inheriting variants in GIGYF2 (p = 0.28).

CONCLUSIONS

We believe that variation in a gene other than GIGYF2 accounts for the previously reported linkage finding on chromosome 2q36-37.

Systemic administration of leptin decreases plasma corticosterone levels: role of hypothalamic norepinephrine

Leptin, an adipocyte-derived hormone, is known to regulate a variety of neuroendocrine functions. It inhibits the hypothalamo-pituitary-adrenal axis (HPA) in several animal models, however, the exact mechanism by which it does so is not known. Since norepinephrine (NE) is a key regulator of the HPA axis, we hypothesized that leptin could suppress HPA activity by decreasing NE levels. To study this, we implanted adult male Sprague-Dawley rats with both a push-pull cannula in the paraventricular nucleus (PVN) and a catheter in the jugular vein. Animals were treated with either 0 or 100 microg or 500 microg of recombinant rat leptin (Lep). Push-pull perfusion was performed from 1000-1600 h. Perfusate samples were collected every 30 min and analyzed for NE levels using HPLC-EC. Blood samples were collected every 60 min and analyzed for corticosterone (CS) levels. To further understand the role of NE in this phenomenon animals were treated with either an alpha1-adrenergic agonist, phenylephrine (PHE; 0.5 mg/kg BW), an alpha2-adrenergic agonist, clonidine (CLON; 0.6 mg/kg BW), or a beta-adrenergic agonist, isoproterenol (ISO; 0.2 mg/kg BW) alone or in combination with 500 microg of Lep. Pre-treatment and hourly post-treatment blood samples were collected, plasma was separated and analyzed for CS levels. Leptin administration decreased NE release in the PVN significantly by 30 min (p<0.05). It also significantly reduced plasma CS levels at 240 and 300 min (p<0.05). Administration of either PHE or CLON in combination with leptin prevented the leptin-induced decrease in CS. In contrast, administration of ISO along with leptin did not prevent the leptin-induced decrease in CS. These results indicate that leptin decreases hypothalamic NE and plasma CS and that this effect is most probably mediated through alpha-adrenergic receptors.

Structural insight into KCNQ (Kv7) channel assembly and channelopathy

Kv7.x (KCNQ) voltage-gated potassium channels form the cardiac and auditory I(Ks) current and the neuronal M-current. The five Kv7 subtypes have distinct assembly preferences encoded by a C-terminal cytoplasmic assembly domain, the A-domain Tail. Here, we present the high-resolution structure of the Kv7.4 A-domain Tail together with biochemical experiments that show that the domain is a self-assembling, parallel, four-stranded coiled coil. Structural analysis and biochemical studies indicate conservation of the coiled coil in all Kv7 subtypes and that a limited set of interactions encode assembly specificity determinants. Kv7 mutations have prominent roles in arrhythmias, deafness, and epilepsy. The structure together with biochemical data indicate that A-domain Tail arrhythmia mutations cluster on the solvent-accessible surface of the subunit interface at a likely site of action for modulatory proteins. Together, the data provide a framework for understanding Kv7 assembly specificity and the molecular basis of a distinct set of Kv7 channelopathies.

Effects of central and systemic administration of leptin on neurotransmitter concentrations in specific areas of the hypothalamus

Leptin, a hormone produced by adipocytes, has been shown to affect a number of central functions, such as regulation of the hypothalamo-pituitary-adrenal axis, feeding, and body weight regulation. Because hypothalamic monoamines are intricately involved in the regulation of these functions, we hypothesized that leptin may produce its effects by altering the activity of these neurotransmitters. To test this hypothesis, male rats received peripheral (0, 100, or 500 μg ip), or central (0 or 5 μg icv) injections of leptin. The animals were killed 5 h later, and their brains were removed, frozen, and sectioned. Serum was collected to measure leptin and corticosterone by RIA. The paraventricular nucleus (PVN), arcuate nucleus (AN), ventromedial hypothalamus (VMH), dorsomedial dorsal nucleus (DMD), median eminence (ME), and medial preoptic area (MPA) were obtained using Palkovits' microdissection technique, and monoamine concentrations in these areas were determined using HPLC-EC. Intraperitoneal administration of leptin increased serum leptin concentrations in a dose-dependent manner ( P < 0.05). Both intraperitoneal and intracerebroventricular administration of leptin decreased serum corticosterone significantly ( P < 0.05). Norepinephrine (NE) concentration decreased significantly in the PVN, AN, and VMH after both intraperitoneal and intracerebroventricular administration of leptin ( P < 0.05). NE concentrations decreased significantly in the DMN after intracerebroventricular administration of leptin ( P < 0.05). Leptin treatment (both ip and icv) decreased dopamine concentrations significantly in the PVN. Serotonin (5-HT) concentration decreased significantly in the PVN after both intraperitoneal and intracerebroventricular injections of leptin and decreased in the VMH only with intracerebroventricular treatment of leptin. Leptin did not affect any of the monoamines in the ME and MPA. These results indicate that both central and systemic administration of leptin can affect hypothalamic monoamines in a region-specific manner, which, in turn, could mediate many of leptin's central and neuroendocrine effects.

Structure of a complex between a voltage-gated calcium channel beta-subunit and an alpha-subunit domain

Voltage-gated calcium channels (Ca(V)s) govern muscle contraction, hormone and neurotransmitter release, neuronal migration, activation of calcium-dependent signalling cascades, and synaptic input integration. An essential Ca(V) intracellular protein, the beta-subunit (Ca(V)beta), binds a conserved domain (the alpha-interaction domain, AID) between transmembrane domains I and II of the pore-forming alpha(1) subunit and profoundly affects multiple channel properties such as voltage-dependent activation, inactivation rates, G-protein modulation, drug sensitivity and cell surface expression. Here, we report the high-resolution crystal structures of the Ca(V)beta2a conserved core, alone and in complex with the AID. Previous work suggested that a conserved region, the beta-interaction domain (BID), formed the AID-binding site; however, this region is largely buried in the Ca(V)beta core and is unavailable for protein-protein interactions. The structure of the AID-Ca(V)beta2a complex shows instead that Ca(V)beta2a engages the AID through an extensive, conserved hydrophobic cleft (named the alpha-binding pocket, ABP). The ABP-AID interaction positions one end of the Ca(V)beta near the intracellular end of a pore-lining segment, called IS6, that has a critical role in Ca(V) inactivation. Together, these data suggest that Ca(V)betas influence Ca(V) gating by direct modulation of IS6 movement within the channel pore.

Treatment compliance among prenatal care patients with substance abuse problems

There is an insufficient number of substance abuse treatment programs available to pregnant women; however, even when women do enroll in treatment, they often choose not to comply with particular components of their treatment. To better understand what factors are associated with a woman's likelihood of compliance with treatment, this study assesses 244 pregnant, substance-using women enrolled in a specialized substance abuse treatment program. Women who complied with treatment referrals are compared with those who did not comply with referrals on various factors including their sociodemographic characteristics, types of substance use before and during pregnancy, experiences of violence before and during pregnancy, and prior substance use treatment. Bivariate analysis found that outpatient treatment compliance was more likely among women who smoked cigarettes before pregnancy, women who had received previous substance abuse treatment, and women whose partner had received previous substance abuse treatment. Outpatient treatment compliance did not vary by sociodemographic characteristics, any other type of substance use, or the women's experiences of violence. Inpatient treatment compliance was more likely among women who received prior substance abuse treatment; however, no other characteristic was found to be associated with inpatient treatment compliance. Logistic regression analyses, which controlled for various factors, suggested that past experiences with substance abuse treatment by the woman or her partner were significantly associated with treatment referral compliance. These findings suggest that the previous treatment experiences of women and their partners are important factors in shaping a successful substance abuse treatment program for pregnant women.

Postexposure rabies prophylaxis protocol for domestic animals and epidemiologic characteristics of rabies vaccination failures in Texas: 1995-1999

OBJECTIVE

To determine whether postexposure rabies prophylaxis (PEP) in domestic animals, as mandated by the state of Texas, has continued to be effective and to evaluate PEP and preexposure rabies vaccination failures from 1995 through 1999.

DESIGN

Retrospective study.

ANIMALS

830 unvaccinated domestic animals (621 dogs, 78 horses, 71 cats, and 60 cattle) that received PEP and 4 animals (3 dogs and 1 horse) that had preexposure rabies vaccination failure.

PROCEDURE

Zoonotic incident case reports from 1995 through 1999 were reviewed for information regarding unvaccinated domestic animals that received PEP according to state protocol after exposure to a rabid animal; reports were also reviewed for information regarding preexposure rabies vaccination failures. The PEP recommendations were to immediately vaccinate the animal against rabies, isolate the animal for 90 days, and administer booster vaccinations during the third and eighth weeks of the isolation period. Rabies vaccines used in the PEP protocol were administered via the route prescribed by the USDA.

RESULTS

From 1995 through 1999, 830 animals received PEP; 4 failures were recorded. Additionally, 4 preexposure rabies vaccination failures were recorded.

CONCLUSIONS AND CLINICAL RELEVANCE

Results of this study indicate that an effective PEP protocol for unvaccinated domestic animals exposed to rabies includes immediate vaccination against rabies, a strict isolation period of 90 days, and administration of booster vaccinations during the third and eighth weeks of the isolation period. This PEP schedule has proven to be effective for control of rabies in domestic animals.

Who gets screened during pregnancy for partner violence?

CONTEXT

Despite recommendations to screen prenatal care patients for partner violence, the prevalence of such screening is unknown.

OBJECTIVES

To estimate the statewide prevalence of partner violence screening during prenatal care among a representative sample of North Carolina women with newborns and to compare women screened for partner violence with women not screened.

DESIGN, SETTING, AND PARTICIPANTS

This investigation examines data gathered through the North Carolina Pregnancy Risk Assessment Monitoring System, a random sample of more than 2600 recently postpartum women who were delivered of newborns between July 1997 and December 1998.

MAIN OUTCOME MEASURES

Self-reports of violence, health service factors, and sociodemographic characteristics.

ANALYSIS

The prevalence of screening was computed, and odds ratios and 95% confidence intervals were used to examine bivariate and multivariable associations between being screened for partner violence and other factors.

RESULTS

Thirty-seven percent of women reported being screened for partner violence during prenatal care. Logistic regression analysis found that women were more likely to be screened if they received prenatal care from (1) a public provider paid by a public source; (2) a private provider paid by a public source; or (3) a public provider paid by a private source.

CONCLUSIONS

These findings suggest that the majority of prenatal care patients in North Carolina are not screened for partner violence. Screening appears to be most highly associated with whether a woman is a patient in the public sector or the private sector, and with the source of payment for prenatal care. Arch Fam Med. 2000;9:1093-1099

Systematic review of risk factors for urinary tract infection in adults with spinal cord dysfunction

Recurrent urinary tract infections (UTIs) occur frequently in persons with neurogenic bladders due to spinal cord dysfunction, resulting in increased morbidity and cost. The authors conducted a systematic review to identify risk factors for UTI using controlled clinical trials, cohort, and cross-sectional studies that assessed risk factors for UTI and included bacteriuria or UTI as an outcome. Twenty-two studies met the inclusion criteria. Quality assessment revealed important methodological deficiencies. Two studies provide evidence supporting increased bladder residual volume as a risk factor. Most of the retrieved studies investigated method of drainage with the consistent finding that persons using intermittent catheterization had fewer infections than those with indwelling catheters. There is conflicting evidence over the value of sterile or "no touch" catheter techniques compared with clean intermittent catheterization. There is insufficient evidence to assess risk due to psychosocial, behavioral, and hygiene factors; sex; level of function; and time since injury.

Epidural cooling for spinal cord protection during thoracoabdominal aneurysm repair: A five-year experience

PURPOSE

We developed and applied a method for providing regional spinal cord hypothermia with epidural cooling (EC) during thoracoabdominal aneurysm (TAA) repair. Preliminary results indicated significant reduction in spinal cord ischemic complications (SCI), compared with historical controls, and a 5-year experience with EC was reviewed.

METHODS

From July 1993 to September 1998, 170 patients with thoracic aneurysms (n = 14; 8.2%) or TAAs (types I and II, n = 83 [49%]; type III, n = 66 [39%]; type IV, n = 7 [4.1%]) were treated with EC. An earlier aneurysm resection was noted in 44% of patients, an emergent operation was noted in 20% of patients, and an aortic dissection was noted in 16% of patients. The EC was successful (mean cerebrospinal fluid [CSF] temperature at cross-clamp, 26.4 +/- 3 degrees C) in 97% of cases, with all 170 patients included in an intention-to-treat analysis. The operation was performed with a clamp/sew technique (98% patients) and selective (T(9) to L(1) region) reimplantation of intercostal vessels. Clinical and EC variables were examined for association with operative mortality and SCI by means of the Fischer exact test, and those variables with a P value less than.1 were included in multivariate logistic regression analysis.

RESULTS

The operative mortality rate was 9.5% and was weakly associated (P =.07) with SCI; postoperative cardiac complications (odds ratio [OR], 35. 3; 95% CI, 5.3 to 233; P <.001) and renal failure (OR, 32.2; 95% CI, 6.6 to 157; P <.001) were the only independent predictors of postoperative death. SCI of any severity occurred in 7% of cases (type I/II, 10 of 83 [12%]; all other types, 2 of 87 [2.3%]), versus a predicted (Acher model) incidence of 18.5% for this cohort (P =. 003). Half the deficits were minor, with good functional recovery, and devastating paraplegia occurred in three patients (2.0%). Independent correlates of SCI included types I and II TAA (OR, 8.0; 95% CI, 1.4 to 46.3; P =.021), nonelective operation (OR, 8.3, 95% CI, 1.8 to 37.7; P =.006), oversewn T(9) to L(2) intercostal vessels (OR, 6.1; 95% CI, 1.3 to 28.8; P =.023), and postoperative renal failure (OR, 23.6; 95% CI, 4.4 to 126; P <.001). These same clinical variables of nonelective operations (OR, 7.7; 95% CI, 1.4 to 41.4; P =.017), oversewn T(9) to L(2) intercostal arteries (OR, 9.7; 95% CI, 1.5 to 61.2; P =.016), and postoperative renal failure (OR, 20.8; 95% CI, 3.0 to 142.1; P =.002) were independent predictors of SCI in the subgroup analysis of high-risk patients, ie, patients with type I/II TAA.

CONCLUSION

EC has been effective in reducing immediate, devastating, total paraplegia after TAA repair. A strategy that combines the neuroprotective effect of regional cord hypothermia, avoiding the sacrifice of potential spinal cord blood supply, and postoperative adjuncts (eg, avoidance of hypotension, CSF drainage) appears necessary to minimize SCI after TAA repair.

The effect of implementing a more comprehensive screening for substance use among pregnant women in North Carolina

OBJECTIVES

Substance use during pregnancy causes significant morbidity and mortality. Screening for substance use provides opportunity for intervention and treatment, but is often overlooked in prenatal care with today's fiscal climate and preconceived ideas about who uses substances. The purpose of this study was to determine the effect of implementing a more comprehensive screening procedure for identifying substance-using pregnant women.

METHODS

Two hundred randomly selected prenatal patients screened using the old procedure for substance use during pregnancy were compared to 400 randomly selected patients screened after implementation of a new, more detailed screening procedure. The old screening approach included three check-boxes concerning substance use during pregnancy: one for "Smoking/alcohol," one for "Drug use (any)," and one for "Drug addiction/alcoholism." The new screening procedure included more detailed questions about the frequency of cigarette, alcohol, and illegal drug use during pregnancy.

RESULTS

Compared with the old approach, the new screening protocol increased reporting of smoking/alcohol use from 21% to 72% (relative risk = 2.63, 95% confidence interval = 2.231, 3.108); reporting of any drug use from 12% to 18% (relative risk = 1.07, 95% confidence interval = 1.002, 1.150); and reporting of alcoholism/drug abuse from 0% to 6% (relative risk = 1.06, 95% confidence interval = 1.038, 1.090).

CONCLUSIONS

Our study suggests that more detailed screening using direct questions concerning the amount and frequency of substance use increases reporting of prenatal substance use as compared to screening approaches using only "yes/no" style check boxes.

Violence in the lives of pregnant teenage women: associations with multiple substance use

Using data from a consecutive sample of approximately 700 prenatal patients aged 12 to 19, the extent of violence and substance use in the lives of these women was examined, as were associations between violence and substance use. The findings show that 29% of the study participants had been victims of violence, with 15% experiencing physical violence only, 5% sexual violence only, and 9% both physical and sexual violence. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression analyses showed that, after controlling for confounding factors, victims were more likely than nonvictims to use cigarettes, alcohol, and illicit drugs, with victims of both physical and sexual violence being the most likely to use each type of substance. Ordinal logistic regression analysis found that, compared to nonvictims, violence victims were more likely to have more severe patterns of substance use (use multiple types of substances), with victims of both physical and sexual violence being the most likely to be multiple substance users. These findings underline the importance of both violence and substance use as health concerns among our youth.

A conserved LIM protein that affects muscular adherens junction integrity and mechanosensory function in Caenorhabditis elegans

We describe here the molecular and functional characterization of the Caenorhabditis elegans unc-97 gene, whose gene product constitutes a novel component of muscular adherens junctions. UNC-97 and homologues from several other species define the PINCH family, a family of LIM proteins whose modular composition of five LIM domains implicates them as potential adapter molecules. unc-97 expression is restricted to tissue types that attach to the hypodermis, specifically body wall muscles, vulval muscles, and mechanosensory neurons. In body wall muscles, the UNC-97 protein colocalizes with the beta-integrin PAT-3 to the focal adhesion-like attachment sites of muscles. Partial and complete loss-of-function studies demonstrate that UNC-97 affects the structural integrity of the integrin containing muscle adherens junctions and contributes to the mechanosensory functions of touch neurons. The expression of a Drosophila homologue of unc-97 in two integrin containing cell types, muscles, and muscle-attached epidermal cells, suggests that unc-97 function in adherens junction assembly and stability has been conserved across phylogeny. In addition to its localization to adherens junctions UNC-97 can also be detected in the nucleus, suggesting multiple functions for this LIM domain protein.

Gene-trapping to identify and analyze genes expressed in the mouse hippocampus

Mice harboring random gene-trap insertions of a lacZ (beta-galactosidase)-neomycin resistance fusion cassette (beta-geo) were analyzed for expression in the hippocampus. In 4 of 15 lines reporter gene activity was observed in the hippocampal formation. In the obn line, enzyme activity was detected in the CA1-3 hippocampal subfields, in hpk expression was restricted to CA1, but in both lines reporter activity was also present in other brain regions. In the third line, kin, reporter activity was robustly expressed throughout the stratum pyrimidale of CA1-3, with only low-level expression elsewhere. The final line (glnC) displayed ubiquitous expression of the reporter and was not analyzed further. Fusion transcripts for the first three lines were characterized; all encode polypeptides with features of membrane-associated signalling proteins. The obn fusion identified a human cDNA (B2-1) encoding a pleckstrin homology (PH) domain, while hpk sequences matched the Epstein-Barr Virus (EBV) inducible G-protein coupled receptor, EBI-1. kin identified an alternative form of the abl-related nonreceptor tyrosine kinase c-arg. Electrophysiological studies on mice homozygous for the insertions revealed normal synaptic transmission, paired pulse facilitation and paired-pulse depression at Schaffer collateral-commissural CA1 synapses, and normal long-term potentiation (LTP) in obn and kin. hpk mice displayed an increase in hippocampal CA1 long-term potentiation (LTP), suggesting a role for this receptor in synaptic plasticity.

Heat-related illnesses

Heat-related illnesses cause 240 deaths annually. Although common in athletes, heat-related illnesses also affect the elderly, persons with predisposing medical conditions and those taking a variety of medications. Symptoms range from mild weakness, dizziness and fatigue in cases of heat edema, to syncope, exhaustion and multisystem complications, including coma and death, in cases of heat stroke. Milder heat-related symptoms can be treated with hydration, rest and removal from the hot environment. Heat stroke, a life-threatening problem, must be treated emergently. Prompt recognition is critical since rapid cooling is the cornerstone of treatment and must not be delayed. Fluid resuscitation with dextrose and normal or half-normal saline is also important. These therapies should be instituted while the patient is being stabilized. Heat illness may be prevented by recognizing which individuals are at risk, using appropriate hydration and paying attention to acclimatization and environmental conditions. Preventive care should include drinking plenty of fluids before, during and after activities, gradually increasing the time spent working in the heat and avoiding exertion during the hottest part of the day.

Geriatric evaluation is a useful adjunct to traditional medical care of the frail older patient

GEMU evaluation is most helpful in complicated cases where frail elderly patients appear likely to require custodial nursing home care in the near future. The best results and most significant reductions in subsequent mortality have occurred in less ill or more recently debilitated elders with a reasonable chance of returning to modified self-care in the home or in assisted living situations. Adapting these principles in an effective, cost-efficient manner for outpatient care is the focus of the majority of current investigations of CGA/GEM. Unfortunately, this option will not be universally available even after the proper parameters for its use are determined. Furthermore, better geriatric assessment and earlier intervention could logically prevent or forestall the patient's functional decline, dependency, and the need for placement. Toward that goal, the reader is referred to a practical guide to efficient outpatient geriatric assessment for general internists and other primary care providers, published by Dr. D.B. Reuben in 1996. A number of questionnaires and rapid screening techniques are included, which make these assessments less cumbersome and thus feasible in this era of austere Medicare reimbursement. However, when managing the care of outpatients with multiple impediments to independent living or hospitalized patients who are partially dependent upon others and are likely to require nursing home placement at (or shortly after) discharge, careful consideration should be given to referral for formal GEM, even if travel to a metropolitan area is required.

Results of an oral rabies vaccination program for coyotes

OBJECTIVE

To determine effectiveness of large-scale distribution of an oral rabies vaccine contained in a palatable bait for halting expansion of a canine rabies epizootic in coyotes (Canis latrans).

DESIGN

Prospective study.

ANIMALS

98 coyotes during prevaccination surveillance and 449 coyotes and 60 other wild animals during postvaccination surveillance.

PROCEDURE

A vaccinia recombinant oral rabies vaccine was inserted into an edible bait for coyotes that also contained tetracycline as a biomarker. Vaccine units were then distributed via aircraft, using automated distribution equipment and flight plans developed by incorporating global positioning system equipment. The target area was along the northern edge of an area that had an epizootic of canine rabies. This area was identified through previously conducted epidemiologic surveillance of rabies cases. During postvaccination surveillance, dental specimens were examined for biomarker evidence of bait acceptance, and serum samples were analyzed for rabies neutralizing antibodies.

RESULTS

Samples from 449 coyotes were obtained during postvaccination surveillance. Seroconversion was detected in 39 of 96 (40.6%) coyotes that had evidence of tetracycline biomarker. Additionally, the number of rabies cases in the target area decreased, and expansion of the epizootic area ceased.

CLINICAL IMPLICATIONS

Mass distribution of an oral rabies vaccine in a palatable bait is an effective means to halt expansion of a rabies epizootic involving coyotes.

Prognostic significance of the initial electrocardiogram in patients with acute myocardial infarction. GUSTO-I Investigators. Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries

CONTEXT

Early risk stratification of patients with myocardial infarction is critical to determine optimum treatment strategies and enhance outcomes, but knowledge of the prognostic importance of the initial electrocardiogram (ECG) is limited.

OBJECTIVE

To assess the independent value of the initial ECG for short-term risk stratification after acute myocardial infarction.

DESIGN

Retrospective analysis of the Global Utilization of Streptokinase and t-PA (alteplase) for Occluded Coronary Arteries (GUSTO-I) clinical trial database.

SETTING

A total of 1081 hospitals in 15 countries.

PATIENTS

From the 41 021 patients enrolled in the overall study, we selected those who presented within 6 hours of chest pain onset with ST-segment elevation and no confounding factors (paced rhythms, ventricular rhythms, or left bundle-branch block) on the ECG performed before thrombolysis was administered (n=34 166).

MAIN OUTCOME MEASURE

Ability of initial ECG to predict all-cause mortality at 30 days.

RESULTS

Most ECG variables were associated with 30-day mortality in a univariable analysis. In a multivariable analysis combining the initial ECG variables and clinical predictors of mortality, the sum of the absolute ST-segment deviation (both ST elevation and ST depression: odds ratio [OR], 1.53; 95% confidence interval [CI], 1.38-1.69), ECG, heart rate (OR, 1.49; 95% CI, 1.41-1.59), QRS duration (for anterior infarct: OR, 1.55; 95% CI, 1.43-1.68), and ECG evidence of prior infarction (for new inferior infarct: OR, 2.47; 95% CI, 2.02-3.00) were the strongest ECG predictors of mortality. A nomogram based on the multivariable model produced excellent discrimination of 30-day mortality (C-index, 0.830).

CONCLUSIONS

In patients presenting with myocardial infarction accompanied by ST-segment elevation, components of the initial ECG help predict 30-day mortality. This information should be valuable in early risk stratification, when the opportunity to reduce mortality is greatest, and may help in assessing outcomes adjusted for patient risk.

Molecular epidemiology of rabies epizootics in Texas

BACKGROUND

Texas is in the midst of two independent epizootics of rabies, involving coyotes (Canis latrans) and domestic dogs (Canis familiaris) in southern Texas and grey foxes (Urocyon cinereoargenteus) in west central Texas. The domestic dog/coyote (DDC) and grey for (TF) rabies virus variants cannot be differentiated by antigenic typing with currently available monoclonal antibodies. These two variants also cannot be distinguished from a third variant, Sonora dog (SD) rabies, that is not enzootic in Texas, but occasionally occurs in animals along the western border with Mexico.

OBJECTIVES

To determine a method for the differentiation of the DDC. TF and SD variants, which is essential for epidemiologic monitoring of the Oral Rabies Vaccination Program (ORVP), a program instituted to control rabies in coyotes and grey foxes in Texas.

STUDY DESIGN

Primers complementary to nucleoprotein sequence of either the DDC or TF rabies virus permit specific reverse transcription and amplification by polymerase chain reaction. In addition, general primers, which recognize a broad range of rabies variants, used in conjunction with a restriction digest for the differentiation of DDC, TF of SD rabies virus were investigated.

RESULTS AND CONCLUSIONS

Of 122 specimens tested with specific primers. 111 (91%) were specifically identified as either DDC (33 samples) or TF (78 samples). Overly stringent conditions, enzyme inhibitors, or limiting RNA may account for the 11 non-amplifications. Amplification of RNA under less stringent conditions, with primers recognizing a broad range of rabies variants followed by digestion with either restriction enzyme Desulfovibrio desulfuricans I (Dde I) or Haemophilus influenzae Rf. (HinfI), was used to identify the 11 isolates that did not amplify with specific primers (6 DDC, 4 TF and 1 SD). In addition to these 11 isolates, the less stringent method of amplification, followed by enzyme digestion has identified a total of 125 additional specimens (26 DDC, 94 TF and 5 SD) that were not tested by variant-specific amplification. These data provide a means to track the spread of the different rabies virus variants and allow the ORVP to plan its vaccine disbursement by defining the two epizootic boundaries.

Characteristics associated with pregnant women's utilization of substance abuse treatment services

There is a dearth of substance abuse treatment programs available to pregnant substance-using women. However, even when specialized substance abuse treatment programs are offered to these high-risk women, some women will choose not to enter treatment. To gain a better understanding concerning the characteristics of pregnant substance-using women related to their decisions regarding treatment utilization, this study compares two groups of substance users: 93 pregnant women who accepted offered substance-related treatment services, and 89 pregnant women who declined the same services. All women were interviewed and information was gathered concerning their sociodemographic characteristics, their types and levels of substance use, substance use by their family members, and their experiences of being victims of violence. Bivariate analyses found that, compared to women who declined treatment, women who accepted treatment were more likely to be African-American, to be single (never married), and to have a significantly greater number of children. Bivariate analyses also showed that, compared to women who declined treatment, women who accepted treatment had more severe substance abuse problems and were more likely to have previously undergone treatment for a substance problem. Women who accepted treatment were twice as likely to have partners who used alcohol and were three times more likely to have experienced physical and/or sexual violence during pregnancy. When logistic regression procedures were used to simultaneously examine the relative impact of all of the variables on treatment utilization, the four strongest independent predictors positively associated with treatment utilization were the women's race (being African-American), the women's use of illegal drugs during pregnancy, the women's past treatment for substance abuse, and the women's use of cigarettes before pregnancy.

Violence and substance use among North Carolina pregnant women

OBJECTIVES

Prenatal patients were studied to examine the proportion of women who had been violence victims, women's patterns of substance use (cigarettes, alcohol, and illegal drugs) before and during pregnancy, and relationships between violence and substance use.

METHODS

More than 2000 prenatal patients in North Carolina were screened for violence and substance use. Relationships between violence and patterns of substance use before and during pregnancy were examined, as well as women's continuation of substance use during pregnancy as a function of violence and sociodemographic factors.

RESULTS

Twenty-six percent of the women had been violence victims during their lives. Before pregnancy, 62% of the women had used one or more substances; during pregnancy, 31% had used one or more substances. Both before and during pregnancy, violence victims were significantly more likely to use multiple substances than nonvictims. Continuation of substance use during pregnancy was significantly more likely among violence victims than nonvictims.

CONCLUSIONS

Care providers should screen women for violence as well as for substance use and should ensure that women are provided with appropriate interventions.

Postexposure rabies prophylaxis and preexposure rabies vaccination failure in domestic animals

OBJECTIVES

To determine the effectiveness of postexposure rabies prophylaxis (PEX) recommendations, as mandated by the state of Texas, and to investigate PEX and preexposure rabies vaccination failures.

DESIGN

Retrospective study.

ANIMALS

1,345 unvaccinated domestic animals that had received PEX and 6 animals that had preexposure rabies vaccination failure.

PROCEDURE

Zoonotic incident case report forms from 1979 through 1994 were reviewed for information about unvaccinated domestic animals that received PEX after exposure to a rabid animal, according to state protocol; the reports were also reviewed for information about preexposure rabies vaccination failures. From 1979 through 1987, the PEX protocol was to immediately vaccinate the animal against rabies, isolate it for 6 months, and administer a booster vaccination 1 month prior to release from isolation. From 1988 through 1994, the protocol was to immediately vaccinate the animal against rabies, isolate it for 90 days, and give booster vaccinations during the third and eighth weeks of the isolation period.

RESULTS

From 1979 through 1987, 713 animals received PEX; 2 failures were recorded. From 1988 through 1994, 632 animals received PEX; 3 failures were recorded. From 1991 through 1994, 6 preexposure rabies vaccination failures were recorded.

CLINICAL IMPLICATIONS

An effective PEX schedule for domestic animals includes immediate rabies vaccination, with a minimum of 1 booster vaccination, and 90 days' strict isolation.

The Drosophila stonewall gene encodes a putative transcription factor essential for germ cell development

The differentiation of Drosophila germ cells is a useful model for studying mechanisms of cell specification. We report the identification of a gene, stonewall, that is required for germ cell development. Mutations in stonewall block proper oocyte differentiation and frequently cause the presumptive oocyte to develop as a nurse cell. Eventually, germ cells degenerate apoptotically. Stonewall is a germ cell nuclear protein; Stonewall has a DNA binding domain that shows similarities to the Myb and Adf-1 transcription factors and has other features that suggest that it is a transcription activating factor. We suggest that Stonewall transcriptional regulation is essential in cystocytes for maturation into specialized nurse cells and oocyte.

Evidence that heterosynaptic depolarization underlies associativity of long-term potentiation in rat hippocampus

1. Whole-cell patch-clamp recording has been used to study the effect of heterosynaptic depolarization on pure N-methyl-D-aspartate (NMDA) receptor-mediated synaptic transmission in the CA1 region of rat hippocampal slices. 2. In neurones voltage clamped at -60 mV, paired-pulse stimulation of one set of Schaffer collateral-commissural fibres resulted in homosynaptic paired-pulse facilitation of the NMDA receptor-mediated excitatory postsynaptic current (EPSCN). In contrast, stimulation of one set of fibres prior to stimulation of a second set of fibres (i.e. heterosynaptic paired-pulse stimulation) did not result in any heterosynaptic interactions. 3. However, under current-clamp conditions, heterosynaptic paired-pulse stimulation resulted in heterosynaptic 'paired-pulse facilitation' of the NMDA receptor-mediated excitatory postsynaptic potential (EPSPN). 4. In neurones held at -50 or -40 mV, perfusion of nominally Mg(2+)-free medium converted the response to heterosynaptic paired-pulse stimulation from 'heterosynaptic facilitation' to 'heterosynaptic depression' of EPSPN. 5. When neurones were held at potentials of between -30 and +40 mV then heterosynaptic paired-pulse stimulation, in normal Mg(2+)-containing medium, resulted in 'paired-pulse depression' of EPSPN. Under voltage-clamp conditions (tested at +40 mV) no heterosynaptic interactions were seen. 6. The time course of 'heterosynaptic facilitation' at -60 mV and of 'heterosynaptic depression' at +40 mV of EPSPN was similar to the time course of EPSCN. 7. We conclude, firstly, that the voltage clamp is able to prevent any voltage breakthrough associated with the synaptic activation of NMDA receptors from influencing neighbouring synapses. Secondly, when the neurone is not voltage clamped these same synapses are strongly influenced by the spreading depolarization generated by the synaptic activation of their neighbours. The time course and direction of this influence are compatible with the hypothesis that spreading synaptic depolarization, leading to a reduction of the voltage-dependent Mg2+ block of synaptic NMDA receptor channels, underlies the property of associativity.

Evidence that presynaptic changes are involved in the expression of LTP and LTD of NMDA receptor-mediated EPSCs in area CA1 of the hippocampus

Plasticity of NMDA receptor-mediated synaptic transmission was studied in the CA1 region of the hippocampus utilising whole cell patch-clamp recording techniques. LTP was associated with a decrease in CV whereas LTD was accompanied by an increase in CV and a decrease in Pr. These data are consistent with LTP and LTD being an opposite expression of the same fundamental process.

Synaptic potentiation of dual-component excitatory postsynaptic currents in the rat hippocampus

1. Whole-cell patch-clamp recording has been used to study tetanus-induced synaptic potentiation of dual-component excitatory postsynaptic currents (EPSCs) in the CA1 region of rat hippocampal slices, following blockade of GABAA and GABAB receptor-mediated synaptic inhibition. 2. At a holding potential of -60 mV, the initial slope of the EPSC (between 10 and 60% of maximum amplitude) provided an accurate measurement of the AMPA receptor-mediated component, and the amplitude of the EPSC at a latency of 100 ms provided the best estimate of the size of the NMDA receptor-mediated component. 3. Neurons were voltage clamped for at least 45 min prior to delivery of a tetanus (test intensity, 100 Hz, 1 s). Measurements at 10 and 30 min following the tetanus were used as indications of short-term potentiation (STP) and long-term potentiation (LTP), respectively. One set of neurons were voltage clamped at -60 mV throughout. These neurons could be subdivided into two populations on the basis of whether or not there was LTP (n = 9), or only STP (n = 6), of the AMPA receptor-mediated component. A second set of neurons were voltage clamped at -60 mV for 30 min and then at -50 mV for 15 min before, during and for 30 min following tetanization. In these experiments there was STP but not LTP (n = 8). 4. In all neurons (n = 23), the time course of the potentiation of the NMDA receptor-mediated component paralleled that of the AMPA receptor-mediated component. In addition, potentiation of the NMDA and AMPA receptor-mediated components were of a similar magnitude. 5. These data demonstrate that it is possible to induce LTP by high frequency stimulation after 45 min of whole-cell recording. Under these conditions, there is a parallel potentiation of the AMPA and NMDA receptor-mediated components of dual-component EPSCs. This constitutes the first evidence, from studies of dual-component synaptic responses, which is consistent with a presynaptic locus of expression of tetanus-induced STP and LTP in the hippocampus.

A comparison of paired-pulsed facilitation of AMPA and NMDA receptor-mediated excitatory postsynaptic currents in the hippocampus

Paired-pulse facilitation of excitatory synaptic transmission was investigated in the CA1 region of rat hippocampal slices using whole-cell patch-clamp recording. To optimise the measurement of excitatory synaptic transmission, gamma-amino-butyric acid (GABA)-mediated synaptic inhibition was eliminated using both GABAA and GABAB antagonists. Pure alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) or N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic currents (EPSCs) were then isolated pharmacologically. Paired-pulse facilitation of either AMPA or NMDA receptor-mediated EPSCs (EPSCA and EPSCN, respectively) was investigated using two stimuli of identical strength delivered at intervals of between 25 and 1000 ms. The paired-pulse facilitation profiles of both EPSCA and EPSCN were similar. Paired-pulse facilitation of EPSCA was independent of holding potential. In contrast paired-pulse facilitation of EPSCN was markedly voltage-dependent; maximum facilitation was recorded at hyperpolarised membrane potentials. At positive membrane potentials there was little or no paired-pulse facilitation and, in most neurones, paired-pulse depression was observed. Voltage-dependence of paired-pulse facilitation of EPSCN was similar in the presence of nominal absence of Mg2+ in the bathing medium, and was unaffected by extensive dialysis of neurones with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA). These data are consistent with a presynaptic locus for paired-pulse facilitation of EPSCA. However, paired-pulse facilitation of EPSCN involves postsynaptic factors.

Rate and predictors of prepubertal bipolarity during follow-up of 6- to 12-year-old depressed children

OBJECTIVE

To investigate the rate and predictors of onset of DSM-III bipolar I and bipolar II disorders among 6- to 12-year-old prepubertal subjects with DSM-III major depressive disorder (MDD) who were followed for a 2- to 5-year period.

METHODS

This was a prospective, blindly rated study of 79 children with MDD and 31 normal control children matched for age, gender, and socioeconomic status. Subjects and a second informant were assessed at 4-month intervals using the Kiddie Schedule for Affective Disorders and Schizophrenia-Present Episode Version-1986 modified to include 4-month interval ratings and to include DSM-III diagnoses. Family history (FH) was assessed using the FH-Research Diagnostic Criteria obtained from the mother about the subject's first- and second-degree relatives.

RESULTS

Bipolarity developed in 31.7% (N = 25) of the children with MDD at a mean age of 11.2 +/- 2.0 years and 80% were prepubertal. Loaded FH and multigenerational FH were significantly associated with bipolar I. Neither prior nor current use of tricyclic antidepressants nor atypical depressive features were predictive.

CONCLUSIONS

These findings strongly support the need to educate families of children with prepubertal-onset MDD about the possibility of the emergence of manic and hypomanic symptoms to encourage early recognition and appropriate treatment.

Epizootic canine rabies transmitted by coyotes in south Texas

Prior to 1988, rabies was reported only sporadically in coyotes. However, in the final 4 months of 1988, Starr County, Tex, which is situated on the US-Mexico border, experienced an epizootic of canine rabies, consisting of 6 laboratory-confirmed cases of rabies in coyotes and of 2 cases in domestic dogs. The first 3 cases were detected in coyotes, and the first case in a domestic dog was observed 84 days after the index case. Adjacent Hidalgo County reported 9 cases of rabies in dogs during the same time that rabid dogs were being reported in Starr County. In 1989, the epizootic primarily involved dogs: 15 dogs in Starr County and 19 dogs in Hidalgo County. Five rabid coyotes were reported in Starr County in 1989, and 1 rabid coyote was reported from Hidalgo County. In 1990, rabies was reported in 3 coyotes and in 31 dogs in Starr County; cases were not detected in Hidalgo County. During 1991, the epizootic expanded approximately 160 km northward, resulting in laboratory-confirmed cases in 42 coyotes and 25 dogs in 10 counties. In 1992, Webb and Willacy Counties became involved; 70 rabid coyotes and 41 rabid dogs were reported in 1992 from the 12-county area. During the first 6 months of 1993, there were 31 rabid coyotes and 38 rabid dogs reported from the same 12 south Texas counties. In May 1993, a raccoon infected with the canine rabies ecotype was reported from Cameron County. Antigenic and genetic analysis revealed the virus ecotype affecting dogs and coyotes to be that associated with urban canine rabies along the US-Mexico border.

Evaluation of commercially available acridinium ester-labeled chemiluminescent DNA probes for culture identification of Blastomyces dermatitidis, Coccidioides immitis, Cryptococcus neoformans, and Histoplasma capsulatum

Four commercially available acridinium ester-labeled DNA probes directed against rRNA were evaluated for their ability to identify Blastomyces dermatitidis, Coccidioides immitis, Histoplasma capsulatum, and Cryptococcus neoformans in culture. rRNA was extracted by sonication of 1- to 2-mm2 portions of cultures of fungi in two chaotropic reagents with glass beads. Following a heat inactivation step, the extracts were hybridized in solution with probes specific for each pathogen. The acridinium ester reporter moiety of nonhybridized probe was selectively hydrolyzed, and chemiluminescence of specific DNA:RNA hybrids was quantitated in relative light units with a luminometer. A positive identification required a relative light unit value of > or = 50,000. Sensitivity and specificity of the probes were determined by probing cultures of the respective pathogenic fungi (target) and nontarget fungi. Both mycelial and yeast forms of the dimorphic fungi (B. dermatitidis and H. capsulatum) were tested. For B. dermatitidis, sensitivity and specificity were 87.8 and 100%, respectively (74 target and 219 nontarget fungi tested). For C. immitis, sensitivity and specificity were 99.2 and 100%, respectively (122 target and 164 nontarget fungi tested). For H. capsulatum, sensitivity and specificity were 100 and 100%, respectively (86 target and 154 nontarget fungi tested). For C. neoformans, sensitivity and specificity were 97 and 100%, respectively (100 target and 230 nontarget fungi tested). For B. dermatitidis, C. immitis, and C. neoformans, repeat testing increased the respective sensitivities to 97.3, 100, and 100%. The high sensitivities and specificities of the probes, the relatively short time (less than 1 h) required to perform the assay, and the availability of standardized reagent kits make the acridinium ester-labeled DNA probes well suited to laboratories in need of a rapid method to identify these fungal pathogens. Further, use of the probes to identify pathogenic fungi as soon as colonies appear on primary recovery media significantly shortens the time to reporting.

Psychosocial adjustment of patients arriving early at the emergency department after acute myocardial infarction

The psychosocial functioning of patients arriving at the emergency department with an acute myocardial infarction early enough to be candidates for treatment with thrombolytic agents was compared with that of those arriving later. Patients who arrived within 3 hours were significantly more anxious when assessed 1 week after admission and had a consistently worse pattern of psychosocial adjustment 3 months after hospital discharge than did those who arrived later. The implications of these findings for efforts to improve early arrival at the emergency department, as well as for medical and psychosocial outcomes after acute myocardial infarction, were considered.

Evaluation of a commercial DNA probe assay for the identification of clinical isolates of Blastomyces dermatitidis from dogs

A DNA probe assay (AccuProbe, Gen-Probe, Inc., San Diego, CA) for culture confirmation of Blastomyces dermatitidis in clinical isolates was evaluated using 72 isolates of B. dermatitidis (62 dog isolates, five from other animals, four human isolates and one soil isolate). In addition, specificity determinations were performed using 28 American Type Culture Collection (ATCC) fungal isolates, other than B. dermatitidis, representing 21 different genera. The non-isotopic hybrid protection assay, that can be performed in less than 1 h, uses a chemiluminescent acridinium ester DNA probe that is homologous to ribosomal RNA sequences of B. dermatitidis. Positive results were obtained with all 72 B. dermatitidis isolates (100% sensitivity). In addition, no positive results were evidenced with the other 28 non-B. dermatitidis fungal isolates, including six strains of Histoplasma capsulatum (100% specificity).

Leprosy in armadillos (Dasypus novemcinctus) from Texas

Tissue sections from 237 nine-banded armadillos (Dasypus novemcinctus) from 51 central Texas counties were examined microscopically for acid-fast bacilli and/or lesions of leprosy. Neither were found. A review of the literature relative to the incidence of leprosy from armadillos in Texas indicates that residents of counties along the Texas Gulf Coast may be at risk of contracting leprosy by handling infected armadillos or their tissues.

Team sports for the severely retarded: training a side-of-the-foot soccer pass using a maximum-to-minimum prompt reduction strategy

A program to teach three severely retarded adults to use a side-of-the-foot soccer pass was evaluated. A 9-step stimulus-response chain was taught using forward chaining. In contrast to usual practice, intensive physical prompts were provided initially to teach each response component, then systematically faded. Approximately 20 lessons (trials) were presented in 20-min sessions. A multiple baseline across subjects design showed that the three trainees achieved the no-prompt criterion after 24, 29, and 22 sessions, respectively. Subanalyses indicated that successive response components were learned only after training was implemented. Follow-up data were obtained 57 and 276 days later in the training room and in a gymnasium; in both settings, criterion was achieved with fewer than three reinstructions.

Demonstration of monoclonal lymphoplasmacytic proliferations by immunofluorescence on routine formalin-fixed, paraffin-embedded tissue

This study explores the use of immunofluorescence on routine formalin-fixed paraffin-embedded tissue to distinguish monoclonal from polyclonal lymphoplasmacytic proliferations. Sixteen tissues containing plasma cell or lymphocyte and plasma cell proliferations were studied. Five-micron sections were deparaffinized in xylene, rehydrated, and treated with 0.1% trypsin for two hours. After washing with phosphate-buffered saline, separate sections were stained with fluorescein-conjugated antibody to IgG, IgA, IgM, IgD, and IgE, and a single section was stained with both fluorescein-conjugated anti-kappa and rhodamine-conjugated antilambda. The latter section was useful to distinguish nonspecific adsorption of the fluorochromes. Where possible, results were correlated with immunoelectrophoretic studies of serum and urine. Eleven specimens with monoclonal and four specimens with polyclonal lymphoplasmacytic proliferations were readily identified, including a case of giant lymph node hyperplasia with a monoclonal IgDK plasma cell component (confirmed by specific absorption studies). Identification of monoclonality by immunofluorescence preceded immunoelectrophoretic identification in one case. One other case gave equivocal results by fluorescence. Further, the method worked on formalin-fixed decalcified tissues, although a somewhat heavier background staining was noted. This method offers a simple, reliable technique to establish or confirm the diagnosis of monoclonal lymphoplasmacytic lesions.

Nesidioblastosis in adults. A surgical dilemma

Nesidioblastosis is the leading cause of hyperinsulinemia in newborns and infants. To our knowledge, it has not been previously reported in adults unless associated with other diseases. Three males and three females, aged 11 to 57 years, are described. Pancreatic resections ranged from 50% to 100%. Postoperatively, three patients were normoglycemic, two were insulin-dependent diabetics, and one had recurrent hypoglycemia controlled by drugs. The histologic findings in adults were very similar to those in infants with nesidioblastosis. It appears that a minimum resection of 75% to 80% of the pancreas will benefit the majority of patients, alleviating hypoglycemia and preventing the development of diabetes.