Morphine-3-D glucuronide stability in postmortem specimens exposed to bacterial enzymatic hydrolysis

Medical examiners frequently rely on the finding of free morphine present in postmortem specimens to assist in certifying deaths associated with narcotics. In vitro hydrolysis of morphine-3-D glucuronide (M3DG) to free morphine was studied using variable specimen pH, initial degree of specimen putrefaction, storage temperature and time, and the effectiveness of sodium fluoride (NaF) preservation. Reagent M3DG was added to opiate-free fresh blood and urine and to autopsy-derived blood specimens. Reagent bovine glucuronidase was also added to certain specimens. Freshly collected and refrigerated NaF-preserved blood produced minimal free morphine, whereas four of five autopsy blood specimens produced free morphine from M3DG. Increased storage time, temperature, and initial degree of putrefaction resulted in greater free morphine generation despite the absence of viable bacteria. Hydrolysis occurring during specimen storage can generate free morphine from M3DG and may result in erroneous conclusions in certifying narcotic deaths.

Substance P (Neurokinin-1) antagonist prevents postoperative vomiting after abdominal hysterectomy procedures

BACKGROUND

The safety and antiemetic efficacy of CP-122,721, a novel neurokinin-1 antagonist, was evaluated when administered alone or in combination with ondansetron.

METHODS

Using a randomized, double-blind, placebo-controlled study design, CP-122,721 was initially compared with placebo and subsequently to ondansetron alone and in combination for prophylaxis against postoperative nausea and vomiting in 243 women undergoing abdominal hysterectomy. In the dose-ranging studies (n = 86), patients received either CP-122,721 100 mg (vs. placebo) or 200 mg (vs. placebo) orally 60-90 min before induction of anesthesia. In the interaction study (n = 157), patients received CP-122,721 200 mg or placebo 60-90 min before induction of anesthesia, and ondansetron 4 mg or saline 2 ml intravenously 15-30 min before the end of surgery. Patients assessed their level of nausea and pain on arrival in the postanesthesia care unit and at 0.5-, 1-, 1.5-, 2-, 4-, 8-, 12-, and 24-h intervals postoperatively. Emetic episodes, need for rescue antiemetic-antinausea medication, postoperative complications, and patient satisfaction were recorded.

RESULTS

In the initial dose-ranging study, only 10% of the patients experienced emesis within the first 8 h after surgery with CP-122,721 200 mg compared with 50% in the placebo group. CP-122,721 200 mg also decreased the need for rescue medication (25% vs. 48%). CP-122,721 100 mg was less effective than 200 mg in decreasing the incidence of repeated episodes of emesis. In the interaction study, 6% of the patients receiving CP-122,721 200 mg orally experienced emesis less than 2 h after surgery compared with 17% with ondansetron alone. With combined therapy, only 2% experienced emesis. In addition, the median times for 75% of patients to remain free from postoperative nausea and vomiting were 82, 75, and 362 min in the ondansetron, CP-122,721, and combination groups, respectively.

CONCLUSIONS

Oral CP-122,721 200 mg decreased emetic episodes compared with ondansetron (4 mg intravenously) during the first 24 h after gynecologic surgery; however, there was no difference in patient satisfaction.

Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning

Aircraft laser-altimeter surveys over northern Greenland in 1994 and 1999 have been coupled with previously reported data from southern Greenland to analyze the recent mass-balance of the Greenland Ice Sheet. Above 2000 meters elevation, the ice sheet is in balance on average but has some regions of local thickening or thinning. Thinning predominates at lower elevations, with rates exceeding 1 meter per year close to the coast. Interpolation of our results between flight lines indicates a net loss of about 51 cubic kilometers of ice per year from the entire ice sheet, sufficient to raise sea level by 0.13 millimeter per year-approximately 7% of the observed rise.

Providing clinical opportunities for youths affected by HIV

Individual counseling, as invaluable as it is for HIV-affected youth, is just one forum in which young people can receive clinical assistance. The youth-centered programs noted previously and others carried out in various agencies around the country offer HIV-affected youth an opportunity to receive clinical experiences while focusing on their strengths and interests. A nonthreatening atmosphere in which many children are invited to participate is essential for helping young people feel comfortable and connected to the agency. When children develop friendships through the agency, they can begin to feel less alone in their situation and more willing to reach out to others--clinicians and peers--for help. An increased trust in the agency can help HIV-affected young people maintain an ongoing connection to services and open the door to traditional counseling. As children become more engaged in the agency and begin to develop a sense of ownership, they may want to take on more responsibility. Leadership programs that focus on young people's skills and talents can help establish the agency as a place that is safe for youths on their own terms. That may involve activities such as older children serving as mentors for younger ones, performing community projects in their neighborhoods, doing outreach to help connect more people to the programs, or designing and running their own conferences for youth. Collaboration with other agencies for special projects can help link children to additional programs and to other youth, thus decreasing their isolation. Childhood and adolescence is a time of rapid changes accompanied by emotional fluctuations. Young people feel emotions intensely, but often lack the cognitive ability necessary to articulate them. When a young person is coping with the illness or death of a parent from AIDS in addition to all the pressures and changes in life, the experience of growing up is even more difficult and complicated. The emotional flux, confusion, and life transitions can lead to impulsive and self-destructive behavior. But childhood and adolescence is also a time of heightened energy, creativity, resilience, and hope. Programs for HIV-affected youth need to balance the attention paid to the challenges they face and the strengths they possess. When allowed to grow and shine, affected young people may begin to express some of their emotional needs. Caring workers can then help them make sense of their experiences and mature into the successful adults they all have the potential to become.

PRINTS-S: the database formerly known as PRINTS

The PRINTS database houses a collection of protein family fingerprints. These are groups of motifs that together are diagnostically more potent than single motifs by virtue of the biological context afforded by matching motif neighbours. Around 1200 fingerprints have now been created and stored in the database. The September 1999 release (version 24.0) encodes approximately 7200 motifs, covering a range of globular and membrane proteins, modular polypeptides and so on. In addition to its continued steady growth, we report here several major changes to the resource, including the design of an automated strategy for database maintenance, and implementation of an object-relational schema for more efficient data management. The database is accessible for BLAST, fingerprint and text searches at http://www.bioinf.man.ac. uk/dbbrowser/PRINTS/

Historical analogies, slippery slopes, and the question of euthanasia

The German Nazi regime has become a standard model for unspeakable things that one should reject. Contemporary people will characterize political opponents, benighted policies, and other undesirable things as “fascist” or “Nazi.” In ethics, and medical ethics in particular, this analogy arises regularly. Therefore, it is not surprising that German people are particularly sensitive about their history. For example, the German high court regularly refers to the Nazi era in its reluctance to accept lethal social activities. This sensitivity surfaced again in 1988, when influential applied ethicist Peter Singer accepted a German invitation to speak to a Symposium on “Bioengineering, Ethics, and Mental Disability.” Singer had also agreed to deliver a separate lecture on the topic “Do severely disabled newborn infants have a right to life?”

Comparison of ondansetron and cyclizine for prevention of nausea and vomiting after day-case gynaecological laparoscopy

We have compared ondansetron 4 mg i.v. and cyclizine 50 mg i.v., in a double-blind, randomized, placebo-controlled study for the prevention of postoperative nausea and vomiting (PONV) for 24 h after day-case gynaecological laparoscopy. Compared with placebo (n = 58), ondansetron (n = 60) and cyclizine (n = 57) reduced significantly the incidence of moderate or severe nausea (30% and 23% vs 52%; P = 0.02 and P = 0.001, respectively) and requirement for escape antiemetic (28% and 16% vs 47%; P = 0.04 and P < 0.001, respectively) before discharge from hospital. There were no significant differences in PONV after discharge. Significantly more patients suffered no PONV before and after discharge after ondansetron and cyclizine compared with placebo (31% and 33% vs 12%; P = 0.02 and P < 0.01, respectively). For diagnostic laparoscopy (n = 74), fewer patients received escape antiemetic after cyclizine than after ondansetron (4% vs 37%; P < 0.01); for laparoscopic sterilization (n = 101), both antiemetics were equally effective. Ondansetron and cyclizine both reduced severe and moderate nausea and the need for antiemetic therapy after day-case gynaecological laparoscopy.

BLAST PRINTS--alternative perspectives on sequence similarity

SUMMARY

An implementation of BLAST for searching the PRINTS database is presented. The interface allows submission of either protein or DNA queries, and returns the familiar form of output, but modified by means of direct links both to the familial discriminators in PRINTS and to fingerprint profile visualization software. The server thus couples the rapidity of BLAST searching with the sensitivity of fingerprint diagnoses, providing alternative perspectives on a given query.

AVAILABILITY

http://www.biochem.ucl. ac.uk/cgi-bin/wright/printsBLAST.cgi

Rapid thinning of parts of the southern greenland ice sheet

Aircraft laser-altimeter surveys over southern Greenland in 1993 and 1998 show three areas of thickening by more than 10 centimeters per year in the southern part of the region and large areas of thinning, particularly in the east. Above 2000 meters elevation the ice sheet is in balance but thinning predominates at lower elevations, with rates exceeding 1 meter per year on east coast outlet glaciers. These high thinning rates occur at different latitudes and at elevations up to 1500 meters, which suggests that they are caused by increased rates of creep thinning rather than by excessive melting. Taken as a whole, the surveyed region is in negative balance.

PRINTS prepares for the new millennium

PRINTS is a diagnostic collection of protein fingerprints. Fingerprints exploit groups of motifs to build characteristic family signatures, offering improved diagnostic reliability over single-motif approaches by virtue of the mutual context provided by motif neighbours. Around 1000 fingerprints have now been created and stored in PRINTS. The September 1998 release (version 20.0), encodes approximately 5700 motifs, covering a range of globular and membrane proteins, modular polypeptides and so on. The database is accessible via the DbBrowser Web Server at http://www.biochem.ucl.ac.uk/bsm/dbbrowser /. In addition to supporting its continued growth, recent enhancements to the resource include a BLAST server, and more efficient fingerprint search software, with improved statistics for estimating the reliability of retrieved matches. Current efforts are focused on the design of more automated methods for database maintenance; implementation of an object-relational schema for efficient data management; and integration with PROSITE, profiles, Pfam and ProDom, as part of the international InterPro project, which aims to unify protein pattern databases and offer improved tools for genome analysis.

Social class and health: the puzzling counter-example of British South Asians

British South Asians (with ancestry from the Indian subcontinent) provided a puzzling exception to the British class gradient in mortality during the 1970s. On the assumption that class gradients in health are produced mainly by gradients in standard of living, this might be due to a break in the relation of class to standard of living (change in class structure), or by a break in the relation of standard of living to patterns of health behaviour and health risk (change in class lifestyles). Data on these characteristics are available from the West of Scotland Twenty-07 Study, where 159 South Asians aged 30-40 (mean age 35) were sampled alongside 319 of the general population in Glasgow. As regards changes in class structure, results indicate that the underclass thesis, which suggests that ethnic minorities are forced into less eligible jobs or into a separate labour market or into unemployment, resulting in a standard of living below that of the general population, still holds good for British South Asians in categories from social class III non-manual downwards. It does not hold good for owners of small businesses, where Sikhs and Hindus in particular have a standard of living equivalent to general population counterparts. However, prosperity is not predictable from levels of education in the subcontinent and from this and other signs it appears that a wholesale redistribution of class chances is occurring among British South Asians, disrupting inter-and intra-generational continuities in the relation between class and standard of living. There is little sign of change in class lifestyles, i.e. in the relation between standard of living and health behaviour or health risk. As yet, though, the new distribution of standard of living is affecting patterns of health behaviour and health risk more strongly than symptom experience or chronic illness, suggesting that a class gradient in health will re-emerge.

Human gene therapy for melanoma: CT-guided interstitial injection

OBJECTIVE

Our intent is to describe the role of CT in the intratumoral injection of Allovectin-7 (Vical, San Diego, CA), an allogeneic class I major histocompatibility complex antigen, HLA-B7, formulated with cationic lipid, in the treatment of metastatic malignant melanoma.

MATERIALS AND METHODS

Ten patients with metastatic malignant melanoma were treated with gene therapy in which we used CT-guided intratumoral injection of plasmid DNA containing the HLA-B7 gene. This therapy was part of a phase I gene therapy trial in patients with metastatic melanoma. CT guidance was chosen as an accurate way to direct gene delivery in patients with deep, impalpable lesions. Tumor locations included pulmonary, mediastinal, hepatic, adrenal, and paracaval sites. Patients in the CT protocol underwent baseline CT studies. Examinations were repeated 2, 4, and 8 weeks after gene therapy and thereafter at 3-month intervals. Both injected and noninjected tumors were measured. CT-guided injections of 10, 50, or 250 micrograms of plasmid DNA were performed with 22-gauge spinal needles. Injection volumes were between 1.0 and 4.0 ml, depending on tumor size. CT-guided core biopsy specimens were obtained (with 18- or 20-gauge needles) from the selected tumor before therapy and 2, 4, and 8 weeks after therapy to assess HLA-B7 plasmid DNA and gene expression. Peripheral blood was analyzed for cytotoxic T lymphocytes directed against HLA-B7.

RESULTS

CT-guided intratumoral injections were successful in delivering genetic material to all patients with impalpable tumors. Significant responses (as defined by a decrease of 25% or more in the product of the length and width of the injected tumor) were observed in six of the 10 patients. One of these six patients who had a solitary lesion remains free of disease 19 months after gene therapy. HLA-B7 protein expression was detected in 89% of biopsy specimens, and plasmid DNA and messenger RNA were detected in 56% and 22% of biopsy specimens, respectively.

CONCLUSION

CT provides a safe, accurate, and efficacious way to monitor and assess tumor progression and response, and it provides guidance for biopsies and intratumoral injections during gene therapy. Significant responses in injected tumors of six of the 10 patients in our study suggest that further clinical trials of this gene therapy are warranted.

Air-coupled Lamb wave tomography

An entirely air-coupled inspection system using a pair of micromachined silicon capacitance transducers has been used to image defects in thin plates of different materials (0.7 mm to 2.22 mm thick) using air-coupled Lamb wave tomography. A filtered back projection algorithm was used in a form of difference tomography to reconstruct images of defects up to 10 mm diameter machined in aluminium and perspex (Plexiglas) plates, as well as in samples of carbon fiber reinforced polymer (CFRP). The technique was able to resolve non-central defects as well as multiple flaws within the scan area. This flexible tomographic system was able to produce images of the change in a variety of different acoustic variables from only one set of experimental data, with success dependent on the size, shape, and location of the defect in the scan area.

A skeletal muscle-specific enhancer regulated by factors binding to E and CArG boxes is present in the promoter of the mouse myosin light-chain 1A gene

The mouse myosin light-chain 1A (MLC1A) gene, expressed in the atria of the adult heart, is one of the first muscle genes to be activated when skeletal as well as cardiac muscles form in the embryo. It is also transcribed in skeletal muscle cell lines at the onset of differentiation. Transient transfection assays of mouse skeletal muscle cell lines with DNA constructs containing MLC1A promoter fragments fused to the chloramphenicol acetyltransferase (CAT) gene show that the first 630 bp of the promoter is sufficient to direct expression of the reporter gene during myotube formation. Two E boxes located at bp -76 and -519 are necessary for this regulation. MyoD and myogenin proteins bind to them as heterodimers with E12 protein and, moreover, transactivate them in cotransfection experiments with the MLC1A promoter in nonmuscle cells. Interestingly, the effect of mutating each E box is less striking in primary cultures than in the C2 or Sol8 muscle cell line. A DNA fragment from bp -36 to -597 confers tissue- and stage-specific activity to the herpes simplex virus thymidine kinase promoter in both orientations, showing that the skeletal muscle-specific regulation of the MLC1A gene is under the control of a muscle-specific enhancer which extends into the proximal promoter region. At bp -89 is a diverged CArG box, CC(A/T)6AG, which binds the serum response factor (SRF) in myotube nuclear extracts, as does the wild-type sequence, CC(A/T)6GG. Both types of CArG box also bind a novel myotube-enriched complex which has contact points with the AT-rich part of the CArG box and adjacent 3' nucleotides. Mutations within the CArG box distinguish between the binding of this complex and binding of SRF; only SRF binding is directly involved in the specific regulation of the MLC1A gene in skeletal muscle cell lines.

Conformational analysis of molecular chains using nano-kinematics

We present algorithms for 3-D manipulation and conformational analysis of molecular chains, when bond lengths, bond angles and related dihedral angles remain fixed. These algorithms are useful for local deformations of linear molecules, exact ring closure in cyclic molecules and molecular embedding for short chains. Other possible applications include structure prediction, protein folding, conformation energy analysis and 3D molecular matching and docking. The algorithms are applicable to all serial molecular chains and make no assumptions about their geometry. We make use of results on direct and inverse kinematics from robotics and mechanics literature and show the correspondence between kinematics and conformational analysis of molecules. In particular, we pose these problems algebraically and compute all the solutions making use of the structure of these equations and matrix computations. The algorithms have been implemented and perform well in practice. In particular, they take tens of milliseconds on current workstations for local deformations and chain closures on molecular chains consisting of six or fewer rotatable dihedral angles.

Clinical microleakage evaluation of a cavity varnish

This clinical study evaluated the microleakage effectiveness of a cavity varnish when used in combination with two types of amalgam: a spherical particle and a dispersed phase alloy. Calcium hydroxide was utilized as the microleakage detection agent. Copalite showed a reduction in microleakage when it was employed with the spherical particle alloy used in this study. This study clinically demonstrated that Copalite is not totally effective in eliminating microleakage.

Initial characterization of heat-induced excess nuclear proteins in HeLa cells

Exposure of mammalian cells to hyperthermia is known to cause protein aggregation in the nucleus. The presence of such aggregates has been detected as the relative increase in the protein mass that is associated with nuclei isolated from heated cells. We have characterized these excess nuclear proteins from the nuclei of heated HeLa cells by two-dimensional gel electrophoresis. The abundance of cytoskeletal elements which co-purify with the nuclei did not increase with exposure to hyperthermia, indicating that these proteins are not part of the excess nuclear proteins. In contrast, several specific polypeptides become newly bound or increase in abundance in nuclei isolated from heated cells. Members of the hsp 70 family were identified as a major component of the excess nuclear proteins. Among the other excess nuclear proteins we identified ten that had apparent molecular weights of 130, 95, 75, 58, 53, 48, 46, 37, 28, and 26 kilodaltons. Since hsp 70 is mainly cytoplasmic in non-heated cells, its association with nuclei in heated cells indicates that one mechanism accounting for the heat-induced excess nuclear proteins is the movement of cytoplasmic proteins to the nucleus. We also obtained evidence that increased binding of nuclear proteins is another mechanism for this effect. No overall increase or decrease in the phosphorylation of nuclear proteins was found to be associated with such altered binding or movement from the cytoplasm to the nucleus.

Propranolol pretreatment reduces cardiorespiratory toxicity due to plain, but not epinephrine-containing, intravenous bupivacaine in rats

The purpose of this study was to evaluate the effects of pretreatment with propranolol on the cardio-respiratory toxicity of bupivacaine, either plain or with epinephrine 1:200,000 (5 micrograms.ml-1) added. Adult male Sprague Dawley rats, anaesthetized with intraperitoneal pentobarbital, were divided into four groups. Groups I and III were pretreated with iv propranolol 150 micrograms.kg-1, and Groups II and IV received iv NS as a placebo. Three minutes later, rats in Groups I and II received plain 0.5% bupivacaine, 4 mg.kg-1, and Groups III and IV received 4 mg.kg-1 of 0.5% bupivacaine with epinephrine, 5 micrograms.ml-1 iv. Five of eight rats pretreated with propranolol survived (Group I), compared with uniform fatality with NS pretreatment (Group II) (P less than 0.05). Addition of epinephrine to the bupivacaine eliminated the protective effect of propranolol. All rats pretreated with propranolol (Group III) or NS (Group IV) died when given bupivacaine with epinephrine. In conclusion, acute propranolol pretreatment reduced the fatal cardiotoxicity due to iv bupivacaine in male Sprague Dawley rats, but the addition of epinephrine 5 micrograms.ml-1 to bupivacaine eliminated the protective effect of propranolol.

Nicardipine reduces the cardio-respiratory toxicity of intravenously administered bupivacaine in rats

The purpose of our study was to examine the effect of intravenous (IV) nicardipine pretreatment (30 micrograms.kg-1), given three minutes before an IV bolus of bupivacaine to determine its effect on the incidence of fatal bupivacaine cardio-respiratory toxicity in adult male Sprague Dawley rats anaesthetized with intraperitoneal pentobarbital. Fifty rats were divided into four groups. Groups I and II (n = 10 each) received 3.5 mg.kg-1 0.5 per cent bupivacaine and Groups III and IV (n = 15 each) received 5.0 mg.kg-1, 0.5 per cent bupivacaine. Groups I and III received pretreatment with normal saline before bupivacaine, whereas Groups II and IV were given pretreatment with nicardipine, 30 mg.kg-1. There was no difference in the incidence of survival between the nicardipine pretreatment group and the saline placebo pretreatment group given 3.5 mg.kg-1, 0.5 per cent bupivacaine (no fatalities in either group). However, there was significant protection by nicardipine pretreatment in the group given 5 mg.kg-1, 0.5 per cent bupivacaine (13 of 15 survived, compared with only 4 of 15 in the saline pretreatment group, P less than 0.001). In conclusion, our data demonstrate that in rats given 0.5 per cent bupivacaine, 5 mg.kg-1, nicardipine pretreatment protected against fatal cardio-respiratory toxicity.