There is more to this fever than meets the eye: A case of neuroleptic malignant-like syndrome (NMLS) secondary to withdrawal of procyclidine and L-dopa on a background of long-standing flupenthixol depot use.

This case report highlights the risk of development of Neuroleptic Malignant-Like Syndrome secondary to withdrawal of procyclidine with brief withdrawal of L-dopa and long-term typical antipsychotic depot. The patient responded to reintroduction of procyclidine, sedation and supportive treatment. The mechanism and management of NMS and NMLS is also reviewed. This case emphasises that any changes in antipsychotic and antiparkinsonian medications should be undertaken with extreme caution and patient should be closely monitored for development of NMLS after alteration in these medications.

Hospitalizations with TB, California, 2009-2017.

BACKGROUND: Hospitalization is a costly event that affects more than half of all TB patients in the United States. State-level hospitalization data are crucial in estimating the cost of TB disease and the financial impact of preventing TB.METHODS: We used California administrative hospital discharge data from 2009 to 2017 to characterize TB hospitalizations in comparison with non-neonatal, non-maternal hospitalizations. TB hospitalization was defined as a hospitalization with a TB ICD-9/10 code as the primary diagnosis. We estimated hospitalization costs in 2017 dollars from reported charges using cost-to-charge ratios.RESULTS: In comparison to persons hospitalized for other conditions, persons hospitalized for TB in 2017 were more likely to be male, of working age, and Asian/Pacific Islander. The median cost for TB hospitalizations was US$22,807 vs. US$11,568 for other hospitalizations. The median length of stay for TB hospitalizations was 12 days compared to 3 days for other hospitalizations. Medicaid was expected to pay for 50% of TB hospitalizations costing US$21,438,208.CONCLUSIONS: Societal cost estimates of TB hospitalization should be updated to reflect long hospital stays and the disproportionate burden on working age persons. This analysis enhances our understanding of the high cost of TB care and underscores the costs averted if TB cases are prevented.

The California Multidrug-Resistant Tuberculosis Consult Service: a partnership of state and local programs.

Background: The US Centers for Disease Control and Prevention recommend expert consultation for multi-drug-resistant tuberculosis (MDR-TB) cases. In 2002, the California MDR-TB Service was created to provide expert MDR-TB consultations. We describe the characteristics, treatment outcomes and management of patients referred to the Service. Methods: Surveillance data were used for descriptive analysis of cases, with consultation during July 2002-December 2012. Clinical consultation data and modified World Health Organization indicators were used to assess the care and management of cases, with consultation from January 2009 to December 2012. Results: Of 339 MDR-TB patients, 140 received a consultation. The proportion of patients receiving a consultation increased from 12% in 2002 to 63% in 2012. There were 24 pre-extensively drug-resistant TB and 5 patients with extensively drug-resistant TB. The majority (n = 123, 88%) completed treatment, 5 (4%) died, 7 (5%) moved before treatment completion, 4 (3%) stopped treatment due to an adverse event and 1 (1%) had an unknown outcome. Indicator data showed that 86% underwent rapid molecular drug susceptibility testing, 98% received at least four drugs to which they had known or presumed susceptibility, and 93% culture converted within 6 months. Conclusions: Consultations with the MDR-TB Service increased over time. Results highlight successful treatment and indicator outcomes.

Contexte : Les Centers for Disease Control and Prevention des Etats Unis recommandent de consulter un expert en cas de tuberculose multirésistante (TB-MDR). En 2002, le California MDR-TB Service a été créé afin de fournir une consultation d'experts en TB-MDR. Nous décrivons les caractéristiques, les résultats du traitement et la prise en charge des patients référés vers ce service.Méthode : Les données de surveillance ont été utilisées pour une analyse descriptive des cas ayant eu une consultation entre juillet 2002 et décembre 2012. Les données de consultation clinique et les indicateurs modifiés de l'Organisation Mondiale de la Santé ont été utilisés afin d'évaluer la prise en charge des cas qui ont bénéficié d'une consultation entre janvier 2009 et décembre 2012.Résultats : Sur 339 patients TB-MDR, 140 ont bénéficié d'une consultation. Cette proportion est passée de 12% en 2002 à 63% en 2012. Il y a eu 24 patients TB pré-ultrarésistante et 5 patients TB ultrarésistante. La majorité (n = 123 ; 88%) a achevé le traitement, 5 (4%) sont décédés, 7 (5%) ont déménagé avant la fin du traitement, 4 (3%) ont arrêté le traitement à cause d'un effet secondaire et 1 (1%) a eu un résultat inconnu. Les indicateurs ont montré que 86% avaient bénéficié d'un test de pharmacosensibilité moléculaire rapide, que 98% avaient reçu au moins quatre médicaments avec une sensibilité connue ou présumée et que 93% ont eu une conversion de culture dans les 6 mois.Conclusion : Les consultations au service de TB-MDR ont augmenté dans le temps. Nous avons mis en lumière les bons résultats du traitement et des indicateurs.

Marco de referencia: Los Centros para el Control y la Prevención de Enfermedades de los Estados Unidos recomiendan que se recurra a la consulta con expertos en los casos de tuberculosis multirresistente (TB-MDR). En el 2002, se creó el California MDR-TB Service en California, con el objeto de proveer consultas de expertos en la materia. En el presente estudio se describen las características, los desenlaces terapéuticos y el tratamiento de los pacientes remitidos a este servicio.Métodos: Se utilizaron los datos de la vigilancia en el análisis descriptivo de los casos que consultaron el Servicio de julio del 2002 a diciembre del 2012. A partir de la base de datos de la consulta y los indicadores modificados de la Organización Mundial de la Salud se evaluó la atención y el tratamiento de los casos que consultaron de enero del 2009 a diciembre del 2012.Resultados: De los 339 pacientes con diagnóstico de TB-MDR, 140 obtuvieron la consulta de expertos. La proporción de pacientes con una consulta aumentó de un 12% en el 2002 al 63% en el 2012. Se atendieron 24 pacientes con TB pre-ultrarresistente y cinco pacientes con TB ultrarresistente. La mayoría completó el tratamiento (n = 123; 88%), 5 pacientes fallecieron (4%), 7 se mudaron antes de haber completado el tratamiento (5%), 4 interrumpieron el tratamiento debido a una reacción adversa (3%) y se desconoció el desenlace de 1 paciente (1%). Según los datos de los indicadores, en 86% de los casos se practicaron pruebas moleculares rápidas de sensibilidad a los medicamentos, el 98% de pacientes recibió como mínimo cuatro fármacos con sensibilidad confirmada o supuesta y el 93% de los pacientes había convertido el cultivo en un lapso de 6 meses.Conclusión: Las consultas al Servicio de expertos en TB-MDR han aumentado con el transcurso del tiempo. Los resultados del estudio ponen de manifiesto la eficacia del tratamiento y revelan indicadores de evolución muy favorables.

Increased tuberculosis risk among immigrants arriving in California with abnormal domestic chest radiographs.

SETTING: Tuberculosis (TB) cases in California, USA, occur predominantly among foreign-born persons, many of whom have abnormal chest radiographs (CXRs) on overseas medical examination. These persons are recommended for follow-up TB evaluation upon arrival in the United States. OBJECTIVE: To estimate the increased TB risk associated with abnormal vs. normal domestic CXRs among individuals arriving with abnormal overseas CXRs. DESIGN: Cox regression analyses of 35 633 foreign-born persons aged 15 years who arrived in California during 1999-2012 with abnormal overseas CXRs and were free of imported active TB. Domestic CXRs were conducted during post-arrival evaluation. Subsequent cases through 2014 were identified from California's TB registry. RESULTS: A total of 121 (0.3%) arrivers developed TB disease. Progression rates were respectively 63.6 (95%CI 50.8-76.4) and 25.4 (95% CI 15.7-35.2) cases/100 000 person-years among persons with abnormal and normal domestic CXRs. Relative to arrivers with normal domestic CXRs, those with abnormal domestic CXRs had an elevated disease risk during the first 4 years after immigration; this increased risk was greatest during the first year (hazard ratio 2.9, 95%CI 1.8-4.8). CONCLUSION: Among arrivers with abnormal overseas CXRs, those with abnormal CXRs upon domestic evaluation have an elevated disease risk and represent an important target group for preventive treatment.

Clinical and bacteriological characteristics associated with clustering of multidrug-resistant tuberculosis.

SETTING: The impact of the genetic characteristics of Mycobacterium tuberculosis on the clustering of multidrug-resistant tuberculosis (MDR-TB) has not been analyzed together with clinical and demographic characteristics. OBJECTIVE: To determine factors associated with genotypic clustering of MDR-TB in a community-based study. DESIGN: We measured the proportion of clustered cases among MDR-TB patients and determined the impact of clinical and demographic characteristics and that of three M. tuberculosis genetic characteristics: lineage, drug resistance-associated mutations, and rpoA and rpoC compensatory mutations. RESULTS: Of 174 patients from California and Texas included in the study, the number infected by East-Asian, Euro-American, Indo-Oceanic and East-African-Indian M. tuberculosis lineages were respectively 70 (40.2%), 69 (39.7%), 33 (19.0%) and 2 (1.1%). The most common mutations associated with isoniazid and rifampin resistance were respectively katG S315T and rpoB S531L. Potential compensatory mutations in rpoA and rpoC were found in 35 isolates (20.1%). Hispanic ethnicity (OR 26.50, 95%CI 3.73-386.80), infection with an East-Asian M. tuberculosis lineage (OR 30.00, 95%CI 4.20-462.40) and rpoB mutation S531L (OR 4.03, 95%CI 1.05-23.10) were independent factors associated with genotypic clustering. CONCLUSION: Among the bacterial factors studied, East-Asian lineage and rpoB S531L mutation were independently associated with genotypic clustering, suggesting that bacterial factors have an impact on the ability of M. tuberculosis to cause secondary cases.

Characteristics and costs of multidrug-resistant tuberculosis in-patient care in the United States, 2005-2007.

OBJECTIVE: A population-based study of 135 multidrug-resistant tuberculosis (MDR-TB) patients reported to the Centers for Disease Control and Prevention (CDC) during 2005-2007 found 73% were hospitalized. We analyzed factors associated with hospitalization. METHODS: We assessed statistically significant multivariable associations with US in-patient TB diagnosis, frequency of hospitalization, length of hospital stay, and in-patient direct costs to the health care system. RESULTS: Of 98 hospitalized patients, 83 (85%) were foreign-born. Blacks, diabetics, or smokers were more likely, and patients with disseminated disease less likely, to receive their TB diagnosis while hospitalized. Patients aged ⩾65 years, those with the acquired immune-deficiency syndrome (AIDS), or with private insurance, were hospitalized more frequently. Excluding deaths, length of stay was greater for patients aged ⩾65 years, those with extensively drug-resistant TB (XDR-TB), those residing in Texas, those with AIDS, those who were unemployed, or those who had TB resistant to all first-line medications vs. others. Average hospitalization cost per XDR-TB patient (US$285 000) was 3.5 times that per MDR-TB patient (US$81 000), in 2010 dollars. Hospitalization episode costs for MDR-TB rank third highest and those for XDR-TB highest among the principal diagnoses. CONCLUSIONS: Hospitalization was common and remains a critical care component for patients who were older, had comorbidities, or required complex management due to XDR-TB. MDR-TB in-patient costs are among the highest for any disease.

Assessing the impact of a nurse-delivered home dried blood spot service on uptake of testing for household contacts of hepatitis B-infected pregnant women across two London trusts.

Despite national guidance recommending testing and vaccination of household contacts of hepatitis B-infected pregnant women, provision and uptake of this is sub-optimal. The aim of this study was to evaluate the use of in-home dried blood spot (DBS) testing to increase testing and vaccination of household contacts of hepatitis B-infected pregnant women as an alternative approach to conventional primary-care follow-up. The study was conducted across two London maternity trusts (North Middlesex and Newham). All hepatitis B surface antigen-positive pregnant women identified through these trusts were eligible for inclusion. The intervention of in-home DBS testing for household contacts was introduced at North Middlesex Trust from November 2010 to December 2011. Data on testing and vaccination uptake from GP records across the two trusts were compared between baseline (2009) and intervention (2010-2011) periods. In-home DBS service increased testing uptake for all ages (P < 0·001) with the biggest impact seen in partners, where testing increased from 30·3% during the baseline period to 96·6% during the intervention period in North Middlesex Trust. Although impact on vaccine uptake was less marked, improvements were observed for adults. The provision of nurse-led home-based DBS may be useful in areas of high prevalence.

Surgery as an Adjunctive Treatment for Multidrug-Resistant Tuberculosis: An Individual Patient Data Metaanalysis.

BACKGROUND: Medical treatment for multidrug-resistant (MDR)-tuberculosis is complex, toxic, and associated with poor outcomes. Surgical lung resection may be used as an adjunct to medical therapy, with the intent of reducing bacterial burden and improving cure rates. We conducted an individual patient data metaanalysis to evaluate the effectiveness of surgery as adjunctive therapy for MDR-tuberculosis. METHODS: Individual patient data, was obtained from the authors of 26 cohort studies, identified from 3 systematic reviews of MDR-tuberculosis treatment. Data included the clinical characteristics and medical and surgical therapy of each patient. Primary analyses compared treatment success (cure and completion) to a combined outcome of failure, relapse, or death. The effects of all forms of resection surgery, pneumonectomy, and partial lung resection were evaluated. RESULTS: A total of 4238 patients from 18 surgical studies and 2193 patients from 8 nonsurgical studies were included. Pulmonary resection surgery was performed on 478 patients. Partial lung resection surgery was associated with improved treatment success (adjusted odds ratio [aOR], 3.0; 95% confidence interval [CI], 1.5-5.9; I(2)R, 11.8%), but pneumonectomy was not (aOR, 1.1; 95% CI, .6-2.3; I(2)R, 13.2%). Treatment success was more likely when surgery was performed after culture conversion than before conversion (aOR, 2.6; 95% CI, 0.9-7.1; I(2)R, 0.2%). CONCLUSIONS: Partial lung resection, but not pneumonectomy, was associated with improved treatment success among patients with MDR-tuberculosis. Although improved outcomes may reflect patient selection, partial lung resection surgery after culture conversion may improve treatment outcomes in patients who receive optimal medical therapy.

Reduced importation of tuberculosis after the implementation of an enhanced pre-immigration screening protocol.

SETTING: Importation of infectious tuberculosis (TB) threatens TB control in California and the United States. OBJECTIVE: To assess the effectiveness of an enhanced pre-immigration screening and treatment protocol to prevent the importation of infectious TB. DESIGN: Retrospective analysis of immigrants ≥ 15 years of age with TB suspect classifications who were screened for TB in their countries of origin before (pre-intervention cohort) and after (post-intervention cohort) implementation of enhanced pre-immigration screening. Enhanced pre-immigration screening added sputum cultures to the existing screening system based on sputum smears for persons with abnormal chest radiographs. RESULTS: The pre- and post-intervention cohorts included respectively 2049 and 1430 immigrants. The occurrence of tuberculosis ≤ 6 months after US arrival in this population decreased following the intervention, from 4.2% (86 cases) to 1.5% (22 cases, P < 0.001). Among pre-intervention cohort cases, 14% were sputum acid-fast bacilli (AFB) smear-positive and 81% were sputum culture-positive for TB, compared with 5% sputum AFB smear-positive (P = 0.46) and 68% sputum culture-positive (P = 0.18) among the post-intervention cohort cases. CONCLUSION: The enhanced pre-immigration screening was associated with a decline in the proportion of immigrants with TB suspect classifications identified with TB within 6 months of arrival in the United States. Continued state and national surveillance is critical to monitor the effectiveness of the revised pre-immigration screening as it is implemented in additional countries.

Linezolid in the treatment of multidrug-resistant tuberculosis.

BACKGROUND: Linezolid is a new antibiotic with activity against Mycobacterium tuberculosis in vitro and in animal studies. Several small case series suggest that linezolid is poorly tolerated because of the side effects of anemia/thrombocytopenia and peripheral neuropathy. To characterize our clinical experience with linezolid, the California Department of Public Health Tuberculosis Control Branch's Multidrug-Resistant Tuberculosis (MDR-TB) Service reviewed cases in which the MDR-TB treatment regimens included linezolid therapy. METHODS: Record review was performed for 30 patients treated with linezolid as part of an MDR-TB regimen. Data were collected on clinical and microbiological characteristics, linezolid tolerability, and treatment outcomes. The dosage of linezolid was 600 mg daily. Vitamin B6 at a dosage of 50-100 mg daily was used to mitigate hematologic toxicity. RESULTS: During 2003-2007, 30 patients received linezolid for the treatment of MDR-TB. Patients had isolates resistant to a median of 5 drugs (range, 2-13 drugs). Of the 30 cases, 29 (97%) were pulmonary; of these 29, 21 (72%) had positive results of acid-fast bacilli smear, and 16 (55%) were cavitary. Culture conversion occurred in all pulmonary cases at a median of 7 weeks. At data censure (31 December 2008), 22 (73%) of 30 patients had successfully completed treatment. Five continued to receive treatment. There were no deaths. Three patients had a poor outcome, including 2 defaults and 1 treatment failure. Side effects occurred in 9 patients, including peripheral and optic neuropathy, anemia/thrombocytopenia, rash, and diarrhea. However, only 3 patients stopped linezolid treatment because of side effects. CONCLUSIONS: Linezolid was well tolerated, had low rates of discontinuation, and may have efficacy in the treatment of MDR-TB.

Fatal systemic phaeohyphomycosis caused by Ochroconis gallopavum in a dog (Canis familaris).

A 5-year-old Shetland Sheepdog was presented with a history of weakness, ataxia, anemia, thrombocytopenia, and occasional seizures. The dog had been treated for 6 months with prednisone for inflammatory bowel disease. A positive titer for Ehrlichia canis was detected 6 months before referral. The initial physical examination revealed a weak, laterally recumbent dog with pale mucous membranes. Neurologic examination revealed multiple neurologic deficits. A complete blood cell count (CBC) revealed normochromic, normocytic, nonregenerative anemia; lymphopenia; thrombocytopenia; and neutrophilic and monocytic leukocytosis. Urinalysis revealed proteinuria, with a specific gravity of 1.045. The dog was unresponsive to treatment and died. At necropsy, there was severe serofibrinous peritonitis and pleuritis, with randomly scattered dark brown necrotic foci present in multiple organs, including liver, spleen, kidney, and pancreatic lymph node. Histologically, there were extensive regions of parenchymal necrosis surrounded by neutrophils admixed with epithelioid macrophages, lymphocytes, and pigmented fungal organisms. Numerous brown, 2 to 6 microm in diameter, septate, branching hyphae, subsequently identified as Ochroconis gallopavum (formerly Dactylaria constricta var. gallopava), were observed.

Investigation of human contacts: a Mycobacterium bovis outbreak among cattle at a California dairy.

BACKGROUND: In May 2002, a Mycobacterium bovis outbreak occurred among cattle at a California dairy. We investigated to determine whether persons were infected after working with the cattle or drinking their raw milk. METHODS: We identified persons with potential contact with infected cattle, including dairy workers, their family members, and slaughterhouse workers. Persons were given a tuberculin skin test (TST), and their occupational and milk-drinking habits were recorded. RESULTS: Of 88 potential contacts, 78 (90%) were given a TST; 33 (43%) had positive TST results, of whom 32 were Mexican-born (RR 15.8, 95%CI 2.3-108.8). No persons had active tuberculosis. Eighteen (72%) dairy workers, 11 (27%) family members, and four (33%) slaughterhouse workers had positive TST results. After adjusting for Mexican-birth and age, dairy workers were no more likely to have positive TST results than others (adjusted RR 1.2, 95%CI 0.6-2.1). Forty-one (62%) dairy staff and their family members drank raw milk from the dairy; 21 (51%) had positive TST results and were Mexican-born. All 13 US-born raw milk drinkers had negative TST results. CONCLUSION: A high prevalence of positive TST results was documented among workers at the affected dairy, although results were not independently associated with contact with infected cattle or milk products. Further assessment of California dairy workers should be considered.

Studies on oil palm trunks as sources of infection in the field.

Diseases of oil palm caused by Ganoderma boninense are of major economic importance in much of South-East Asia. This paper describes results from an ongoing field trial concerning the spread of the pathogen from artificially inoculated trunks used to simulate spread from windrowed trunks. Three planting distances for bait seedlings revealed that the closer the seedling was planted to the source of inoculum the sooner it succumbed to the disease. However, infection only occurred when the trunks were mounded (covered with soil), and seedlings planted around uncovered trunks (at any distance) have showed no symptoms of disease to date. Isolates are being collected from infected plants and molecular analysis is being undertaken to give more information on the spread of the pathogen.

Investigations on the causes of upper stem rot (USR) on standing mature oil palms.

Three different trials to examine the cause of upper stem rot (USR) infection in oil palm failed to achieve any infection. In the first experiment, inoculum was applied as colonised rubber wood blocks or as spore suspensions. In the second experiment, particular attention was given to ensure that the Ganoderma spores were freshly collected to maintain viability but no infection was observed around the inoculation sites of any of the different oil palm tissues treated. Lastly in the third experiment, both monokaryotic and dikaryotic mycelial cultures were applied directly to cut fronds, which were protected with a moist covering, but no infection was detected after more than two years. Failure to achieve infection by direct inoculation would indicate that USR does not arise from direct infection of living tissues by Ganoderma spores or mycelium, this is probably because of insufficient inoculum potential to cause infection. It is suggested that USR infection is achieved only when a sufficiently large source of inoculum has built up in dead material, probably in frond axils, and this allows invasion of the living tissues.

A toroid model for in vitro investigations of toxic shock syndrome toxin-1 production.

Human behaviours and consumer products may affect vaginal microbial ecology, thereby influencing women's health. Relevant experimentation systems are needed to understand such possible links. Here, we describe the development of a practical semi-solid in vitro model to assess the effects of interactions between vaginal environment and the presence of tampons, on bacterial communities, including the production of toxic shock syndrome toxin-1 (TSST-1) by Staphylococcus aureus.

Evaluation of tuberculosis contact investigations in California.

OBJECTIVE: To estimate the burden of tuberculosis (TB) contact investigations in California, assess outcomes and effectiveness, and identify performance gaps. METHODS: Aggregate program management reports were used to examine contact investigations conducted for pulmonary TB cases reported between 1 July 1999 and 30 June 2000 in California. Findings were compared to national objectives, and performance gaps were identified. Costs were estimated, and effectiveness of TB case detection and prevention was assessed. RESULTS: A total of 2032 acid-fast bacilli sputum smear-positive and sputum smear-negative/culture-positive cases was reported; 17774 contacts were elicited, and 15582 (88%) contacts were evaluated. TB disease and latent tuberculosis infection (LTBI) were diagnosed in 111 (<1%) and 4609 (30%) contacts, respectively; 1958 (43%) contacts with LTBI completed treatment. Costs of contact investigations were estimated at dollars 4.8 million; 81% of expected TB cases were detected, but only 35% of cases expected to occur within 2 years following the investigation were prevented. CONCLUSIONS: California's performance did not meet national objectives for contact evaluation or treatment completion; improved effectiveness of contact investigations in California is needed. Although analysis of existing contact investigation surveillance data provided a macro-level view of performance gaps, expanded surveillance data are required to inform interventions.

Adenovirus type 3 viremia in an adult with toxic shock-like syndrome.

Surveillance by the Unexplained Deaths and Critical Illnesses Project (UNEX) uncovered a novel presentation of adenovirus type 3 infection that satisfied the criteria for toxic shock-like syndrome in a 28-year-old immunocompetent man. Adenovirus may be a cause of toxic shock syndrome; surveillance systems such as UNEX may uncover additional causes of this and other clinically defined infectious syndromes.

Fatty acid derivatives of clozapine: prolonged antidopaminergic activity of docosahexaenoylclozapine in the rat.

Stable amides of clozapine derived from fatty acids prominent in cerebral tissue might enhance the central activity of clozapine and reduce its exposure to peripheral tissues. Such derivatives might enhance the safety of this unique drug, which is the only agent with securely established superior antipsychotic effectiveness, but with a risk of potentially lethal systemic toxicity. Amide derivatives of clozapine were prepared from structurally varied fatty acid chlorides and evaluated for ability to inhibit behavioral arousal in rat induced by dopamine agonist apomorphine and to induce catalepsy. Their duration-of-action and potency were compared to free clozapine, and concentrations of clozapine were assayed in brain and blood. Selected agents were also evaluated for affinity at dopamine receptors and other potential drug-target sites. Clozapine-N-amides of linoleic, myristic, oleic, and palmitic acids had moderate initial central depressant activity but by 6 h, failed to inhibit arousal induced by apomorphine. However, the docosahexaenoic acid (DHA) derivative was orally bioavailable, 10-times more potent (ED(50) 5.0 micromol/kg) than clozapine itself, and very long-acting (>/= 24 h) against apomorphine, and did not induce catalepsy. DHA itself was inactive behaviorally. Clozapine showed expected dopamine receptor affinities, but DHA-clozapine was inactive at these and other potential target sites. After systemic administration of DHA-clozapine, serum levels of free clozapine were very low, and brain concentrations somewhat lower than after administering clozapine. DHA-clozapine is a long-acting central depressant with powerful and prolonged antidopaminergic activity after oral administration or injection without inducing catalepsy, and it markedly reduced peripheral exposure to free clozapine. It lacked the receptor-affinities shown by clozapine, suggesting that DHA-clozapine may be a precursor of free, pharmacologically active clozapine. Such agents may represent potential antipsychotic drugs with improved central/peripheral distribution, and possibly enhanced safety.

Identification and characterization of gelatin-cleavage activities in the apically located extracellular matrix of the sea urchin embryo.

We have identified and partially characterized several gelatinase activities associated with the sea urchin extraembryonic matrix, the hyaline layer. A previously identified 41-kDa collagenase/gelatinase activity was generally not found to be associated with isolated hyaline layers but was dissociated from the surface of 1-h-old embryos in the absence of Ca2+ and Mg2+. While hyaline layers, freshly prepared from 1-h-old embryos, were devoid of any associated gelatinase activities, upon storage at 4 degrees C for 4 days, a number of gelatin-cleavage activities appeared. Comparative analysis of these activities with the 41-kDa collagenase/gelatinase revealed that all species were inhibited by ethylenediamine tetraacetic acid but were refractory to inhibition with the serine protease inhibitors, phenylmethyl sulfonyl fluoride and benzamidine. In contrast, the largely Zn2+ specific chelator 1,10-phenanthroline had markedly different effects on the gelatinase activities. While several of the storage-induced, hyaline-layer-associated gelatinase activities were inhibited, the 41-kDa collagenase/gelatinase was refractory to inhibition as was a second gelatinase species with an apparent molecular mass of 45 kDa. We also examined the effects of a series of divalent metal ions on the gelatin-cleavage activities. In both qualitative and quantitative assays, Ca2+ was the most effective activator while Mn2+, Cu2+, Cd2+, and Zn2+ were all inhibitory. In contrast, Mg2+ had a minimal inhibitory effect on storage-induced gelatinase activities but significantly inhibited the 41-kDa collagenase/gelatinase. These results identify several distinct gelatin-cleavage activities associated with the sea urchin extraembryonic hyaline layer and point to diversity in the biochemical nature of these species.