Multilocus phylogeographic assessment of the California Mountain Kingsnake (Lampropeltis zonata) suggests alternative patterns of diversification for the California Floristic Province.

Phylogeographic inference can determine the timing of population divergence, historical demographic processes, patterns of migration, and when extended to multiple species, the history of communities. Single-locus analyses can mislead interpretations of the evolutionary history of taxa and comparative analyses. It is therefore important to revisit previous single-locus phylogeographic studies, particularly those that have been used to propose general patterns for regional biotas and the processes responsible for generating inferred patterns. Here, we employ a multilocus statistical approach to re-examine the phylogeography of Lampropeltis zonata. Using nonparametic and Bayesian species delimitation, we determined that there are two well-supported species within L. zonata. Ecological niche modelling supports the delimitation of these taxa, suggesting that the two species inhabit distinct climatic environments. Gene flow between the two taxa is low and appears to occur unidirectionally. Further, our data suggest that gene flow was mediated by females, a rare pattern in snakes. In contrast to previous analyses, we determined that the divergence between the two lineages occurred in the late Pliocene (c. 2.07 Ma). Spatially and temporally, the divergence of these lineages is associated with the inundation of central California by the Monterey Bay. The effective population sizes of the two species appear to have been unaffected by Pleistocene glaciation. Our increased sampling of loci for L. zonata, combined with previously published multilocus analyses of other sympatric species, suggests that previous conclusions reached by comparative phylogeographic studies conducted within the California Floristic Province should be reassessed.

A prospective evaluation of the feasibility and utility of additional tools to obtain information from recently diagnosed HIV infected patients.

QUESTION UNDER STUDY: Can additional information be obtained from recently HIV diagnosed individuals? METHODS: A 1-year prospective Swiss study, including all newly diagnosed HIV-infected patients. Information on circumstances of HIV infection was collected through physician- and patient questionnaires and patient interviews. Information on timing of infection was linked with an HIV-antibody avidity assay. RESULTS: Of 710 newly HIV diagnosed patients, 543 (76%) physician questionnaires (PhyQ) and 145 (20%) patient questionnaires (PaQ) were returned. PhyQ required fewer reminders (57% vs 28% spontaneous return). Patients whose doctors had returned the PhyQ were comparable to total population group. In contrast, a strong bias towards well educated recently infected Swiss men having sex with men (MSM) was seen in patients returning PaQ or agreeing to an interview. 83% of patients claimed that they knew the infection source and 85% infection place. Unprotected sexual contact was the most frequently cited infection source (92%; n = 404). Men mainly claimed occasional (43%) and women steady (61%) partners as the most likely source of HIV infection. Serum for timing of infection was available in 98% of patients. Recent infections (RI) were highest in MSM (51%) and intravenous drug users (IDU, 54%). Compared to women, heterosexual men were more than twice as likely to be diagnosed with a RI. CONCLUSION: Relevant additional information on circumstances of HIV infection in newly diagnosed patients can easily be collected from treating physicians. Collecting information from patients is not a feasible option, with the exception of qualitative interviews in a selected group of patients.

[Is there a special responsibility of HIV-positive people? A discussion paper]. / Haben HIV-Positive eine besondere Verantwortung? Ein Diskussionsbeitrag.

In the 1980s, most Western countries decided to opt for a new public health approach based on learning strategies to fight HIV/AIDS. Within the new public health paradigm, every sexually active person protects him-/herself, whereas it is the infected people that bear the burden of prevention according to old public health. The paper begins with a clear statement for the new public health approach that includes self-protection and the protection of civil rights. It argues that this approach is still valid under the changing circumstances due to combination therapies and the developments related to them, such as the introduction of routine HIV screening in some countries. On this background, the paper examines from an ethical perspective to what extent people with HIV have a responsibility in HIV prevention. The paper argues that a person with HIV has a responsibility to protect his/her partner in the case of a relationship of love. On the other hand, in the case of "purely" sexual encounters, each person is responsible for his/her own security and should not rely on the other. This position also helps to clarify prevention messages. In conclusion, the paper shows how morality evolves into ethical positions and then translates into the law. It finally claims for stronger obligations for sex businesses to support HIV prevention.

S-methyl N-butylthiocarbamate sulfoxide: selective carbamoylating agent for mouse mitochondrial aldehyde dehydrogenase.

Liver mitochondrial low-Km aldehyde dehydrogenase (ALDH2, EC 1.2.1.3), the isoform responsible for the conversion of acetaldehyde to acetate, is inhibited by the sulfoxide bioactivation products of Et2NC(O)SMe (from the alcohol aversion drug disulfiram), Pr2NC(O)SEt (the herbicide S-ethyl N,N-dipropylthiocarbamate), and BuNHC(O)SMe (from the fungicide benomyl). This study tested the hypothesis that bioactivated BuNHC(O)SMe, the most potent of these thiocarbamates, is a selective carbamoylating agent for ALDH2 of mouse liver in vivo and in vitro. [14C]BuNHC(O)SMe administered i.p. to mice labeled one principal mitochondrial protein, which cochromatographed with ALDH activity by in-gel assay after isoelectric focusing. The labeled protein was isolated by isoelectric focusing (pI 6.1) and SDS-PAGE (54 kDa) and identified as ALDH2 by sequencing of peptides from a tryptic digest. In vivo at 1.5 mg/kg, enzyme inhibition was 80%, and ALDH2 was the only mitochondrial protein labeled extensively, illustrating the outstanding potency and specificity. ALDH2 also was labeled upon incubation of mouse liver mitochondria with [14C]BuNH-C(O)SMe in the presence of microsomes (P450) and NADPH. In contrast, under similar conditions, [14C]Pr2NC(O)SEt sulfoxide labeled primarily two other proteins at approximately 58 and approximately 61 kDa, establishing a very different selectivity for the two sulfoxides. These findings are of interest relative to selective inhibitors and carbamoylating agents for ALDH2 and to alcohol aversion upon exposure to herbicides and fungicides.

Phylogeography of the California mountain kingsnake, Lampropeltis zonata (Colubridae).

The phylogeography of the California mountain kingsnake, Lampropeltis zonata, was studied using mitochondrial DNA sequences from specimens belonging to the seven recognized subspecies and collected throughout the range of the species. Maximum parsimony and maximum likelihood methods identified a basal split within L. zonata that corresponds to southern and northern segments of its distribution. The southern clade is composed of populations from southern California (USA) and northern Baja California, Mexico. The northern clade is divided into two subclades, a 'coastal' subclade, consisting of populations from the central coast of California and the southern Sierra Nevada Mountains of eastern California, and a 'northeastern' subclade, mainly comprised of populations north of the San Francisco Bay and from the majority of the Sierra Nevada. We suggest that past inland seaways in southwestern California and the embayment of central California constituted barriers to gene flow that resulted in the two deepest divergences within L. zonata. Throughout its evolutionary history, the northern clade apparently has undergone instances of range contraction, isolation, differentiation, and then expansion and secondary contact. Examination of colour pattern variation in 321 living and preserved specimens indicated that the two main colour pattern characters used to define the subspecies of L. zonata are so variable that they cannot be reliably used to differentiate taxonomic units within this complex, which calls into question the recognition of seven geographical races of this snake.

Diffraction from metallic gratings with locally varying profile forms.

Measurements of the diffraction characteristics of one-dimensional surface-relief gratings of locally varying profile are compared with rigorous diffraction theory. These gratings result from the superposition of two linear sinusoidal gratings of uniform depth for which the relative phase between the two gratings varies slowly with position. The resultant surface profile exhibits a relatively large-period variation in profile form. The periodic variation in diffraction efficiency that results yields a visual moiré pattern that has interesting asymmetry and polarization properties that alter as the viewing conditions are changed; the gratings can be exploited by diffractive optically variable devices for document security.

Mechanism for benomyl action as a mitochondrial aldehyde dehydrogenase inhibitor in mice.

Benomyl (a non-thio fungicide) inhibits hepatic mitochondrial low-Km aldehyde dehydrogenase (mALDH or ALDH2) in ip-treated mice by 50% (IC50) at 7.0 mg/kg, which is surprisingly the same potency range as that for several dithiocarbamate fungicides (and the related alcohol abuse drug disulfiram) and thiocarbamate herbicides previously known for their alcohol-sensitizing action. The mechanism by which benomyl inhibits mALDH was therefore examined, first by comparing the metabolism of benomyl with the aforementioned mono- and dithiocarbamates and second by evaluating the inhibitory potency of the benomyl metabolites. Benomyl in ip-treated mice is converted, via butyl isocyanate, S-(N-butylcarbamoyl)glutathione, and S-(N-butylcarbamoyl)cysteine, to S-methyl N-butylthiocarbamate (MBT), identified as a transient metabolite in liver. MBT is >10-fold more potent than benomyl or butyl isocyanate as an in vivo mALDH inhibitor and is also more potent than the intermediary S-(N-butylcarbamoyl) conjugates. Benomyl and MBT inhibit mouse hepatic mALDH in vitro with IC50s of 0.77 and 8.7 microM, respectively. The potency of MBT is greatly enhanced by fortification of the mitochondria with NADPH alone or plus microsomes giving IC50s of 0.50 and 0.23 microM, respectively. This activation of MBT is almost completely blocked by the cytochrome P450 inhibitor N-benzylimidazole but not by several other cytochrome P450 inactivators. MBT (probably following bioactivation) inhibits mALDH in vivo with an IC50 of 0.3 mg/kg. Two candidate activation products were synthesized for potency determinations. N-Hydroxy MBT (prepared via the trimethylsilyl derivative) was not detected as an MBT metabolite; its low potency also rules against N-hydroxylation as the activation process. MBT sulfoxide, from oxidation of MBT with magnesium monoperoxyphthalate in water, is one of the most potent inhibitors known for mALDH and yeast ALDH in vitro (IC50 0.08-0.09 microM). These findings are consistent with a six-step bioactivation of benomyl, via the metabolites above and N-butylthiocarbamic acid, with MBT as the penultimate and MBT sulfoxide as the ultimate inhibitor of mALDH.

The 6 volt battery for implantable cardioverter/defibrillators.

The usage of a 6 V lithium manganese dioxide battery results in a significant reduction of capacitor loading time within implantable defibrillators/cardioverters. In order to provide ERI indication a new cathode formulation has been developed. The battery shows no voltage delays, a low self-discharge and fulfilled all requirements to an energy source for an implantable device.

S-methylation as a bioactivation mechanism for mono- and dithiocarbamate pesticides as aldehyde dehydrogenase inhibitors.

S-Methylation is a new bioactivation mechanism for metam and metabolites of methyl isothiocyanate and dazomet in mice. These soil fumigants are converted to S-methyl metam [MeNHC(S)SMe] which reaches peak levels in liver, kidney, brain, and blood 10-20 min after intraperitoneal (ip) treatment. The half-life of S-methyl metam administered ip is 8-12 min in each of these tissues. S-Methyl metam-oxon [MeNHC(O)SMe] is also detected as a metabolite of each of these soil fumigants on analysis by gas chromatography/mass spectrometry with chemical ionization. The conversion of methyl isothiocyanate to S-methyl metam and its oxon probably involves conjugation with glutathione, hydrolysis to S-(N-methylthiocarbamoyl)-cysteine, cleavage by cysteine conjugate beta-lyase to release metam, and finally methylation and oxidative desulfuration. Metam and dazomet are converted to S-methyl metam by mouse liver microsomes on fortification with S-adenosylmethionine. Metam, methyl isothiocyanate, dazomet, and three metabolites (metam-oxon [MeNHC(O)SH], MeNHC(S)SMe, and MeNHC-(O)SMe) administered ip to mice at 40 mg/kg inhibit low-Km liver mitochondrial aldehyde dehydrogenase and elevate ethanol-dependent blood and brain acetaldehyde levels. Several fungicides including the dialkyldithiocarbamates as the disulfide (thiram and the related alcohol-abuse drug disulfiram) and metal salts (ziram) also yield S-methyl thiocarbamate metabolites. Eight S-alkyl and S-(chloroallyl) thiocarbamate herbicides (EPTC, molinate, butylate, vernolate, pebulate, diallate, sulfallate, and triallate), but not their S-chlorobenzyl analog (thiobencarb), undergo sequential liberation of the thiocarbamic acid and then S-methylation, forming the S-methyl thiocarbamates which are new metabolites and potential aldehyde dehydrogenase inhibitors. The S-methyl mono- and dithiocarbamate metabolites of these herbicides and fungicides are easily identified by retention time on gas chromatography and by mass spectrometry giving [MH]+ plus [R1R2NCO]+ or [R1R2NCS]+, respectively, as the two major ions.

Metabolism of cycloate in radish leaf: metabolite identification by packed capillary flow fast atom bombardment tandem mass spectrometry.

The metabolism of cycloate, a thiocarbamate herbicide, was investigated in mature radish leaf. Twelve new metabolites were identified by liquid chromatographic/mass spectrometric analysis using fast atom bombardment and packed capillary liquid chromatography columns. Full-scan and tandem mass spectrometric methods were employed. Application of the on-column focusing technique resulted in identifications with injections of as little as 15 ng of metabolite (20 ppb in radish). This injection technique allows the practical use of packed capillary liquid chromatography/mass spectrometry in sample-limited applications. Cycloate is oxidized to several ring-hydroxylated isomers that are subsequently glucosylated and esterified with malonic acid. Cycloate is also conjugated with glutathione. Metabolic hydrolysis of the glutathione conjugate formed a cysteine conjugate that is further metabolized by amidation with either malonic or acetic acid. Transamination of the cysteine conjugate gave a thiolactic acid derivative. Metabolites were also identified that were the result of both ring-hydroxylation and conjugation with glutathione. One of these, an N-acetylcysteine conjugate, is the first report of a mercapturic acid in plants. The structures of two of the new metabolites were confirmed by chemical synthesis.

[Epidemiology and prevention of AIDS in the population]. / Epidemiologie und Prävention von AIDS in der Bevölkerung.

Routes of transmission of HIV which play an important role in the population are known. Sexual transmission, infection through needle sharing by i.v. drug addicts, accidental blood contacts and transmission from the infected pregnant mother to her child are seen. The number of new infections depends on the number of already infected individuals, the rapidity of spread and the spread potential. The infection can be rapidly spread among drug addicts, several drug users may be infected at the same time through needle sharing. In the general population the spread potential through sexual transmission is high. The AIDS prevention campaign in Switzerland aims at preventing new infections and at building up solidarity. With the STOP-AIDS campaign a broad effect in the population could be reached. The most important goals in the near future are to have an effect in depth in some target groups and to promote individual counselling.

Plasma and cerebrospinal fluid concentration of phenylacetic acid in humans and monkeys.

A rapid and reliable mass-fragmentographic method for assay of plasma and cerebrospinal fluid (CSF) concentrations of free and conjugated phenylacetic acid (PAA) is described. The method is used to compare plasma and CSF concentrations of PAA in humans and monkeys. Both packed and capillary columns are used. In humans approximately 45% of total plasma PAA is conjugated in contrast to approximately 60% in monkeys. Both free and conjugated PAA concentrations tend to be higher in monkeys than in humans. Plasma mean concentration of total PAA in humans and monkeys are, respectively, 459.1 and 838 ng/ml. Approximately 55 and 25% of total PAA in the CSF are conjugated in humans and monkeys, respectively. Total PAA mean concentrations in human and monkey CSF are 41.6 and 84.2 ng/ml. Because over 90% of total urine PAA in humans is conjugated, it is concluded that over 50% of urine phenylacetylglutamine may be derived from kidney conjugation of free plasma PAA and/or from the kidney's preferential filtration of conjugated PAA as contrasted with free PAA.

Treatment of compulsive rituals with visual screening: a case study with long-term follow-up.

The present study reports on the use of visual screening, a mildly aversive response suppression procedure, as a treatment for reducing compulsive behaviors in a four and one-half year-old developmentally disabled boy. Two distinct patterns of compulsive responding were observed: repetitive (stereotyped) shoe-related behaviors and a ritualistic shoe-related act. The effect of visual screening on repetitive shoe-related responses was initially evaluated in a laboratory setting under A-B-A-B-B1 experimental conditions and systematically extended to the classroom setting in multiple baseline fashion. Visual screening was also contingently applied as treatment for the shoe-related ritual, with the effects analyzed using a similar multiple baseline format across hospital residential unit and natural home settings. Results of the study indicated that visual screening was an effective treatment for suppressing both forms of the subject's compulsive responding and that it was an easily learned and administered procedure from both staff and parent perspectives. Follow-up data across 12 months were obtained and indicated that the effect of treatment was exceptionally durable.

Drug effect on blink rates in rhesus monkeys: preliminary studies.

Various drugs that alter central monoamine activity were given to monkeys to determine effects on blink rate. Chronic pargyline treatment raised the mean +/- SD blink rate slightly to 18.2 +/- 5.3 blinks/90 sec. When phenylethylamine was added to chronic pargyline treatment, blinks increased from a base line of 16.8 +/- 7.6 blinks/90 sec to 37 +/- 15 blinks/90 sec. Apomorphine (0.36 mg/kg) raised blinks from a base lone of 12.2 +/- 2.8 blinks/90 sec. to 41.9 +/- 10.3 blinks/90 sec. and reversed a decrease in blinking caused by haloperidol. The neurochemical basis of blinking and implications for tardive dyskinesia are discussed.

Lymphocyte monoamine oxidase and plasma prolactin and growth hormone in tardive dyskinesia.

Twelve elderly women with tardive dyskinesia were matched with 12 patients without dyskinesia. Lymphocyte monoamine oxidase (MAO) activity and plasma prolactin and growth hormone concentrations were determined "blind" in these 12 pairs of patients. Chronic schizophrenic patients with tardive dyskinesia had significantly lower lymphocyte MAO activity as compared to controls. Organic brain syndrome patients with dyskinesia did not differ from controls in the lymphocyte MAO activity. These results with lymphocyte MAO parallel our earlier findings on platelet MAO. No significant differences were found between dyskinesia group and controls in the plasma prolactin and growth hormone concentrations. Possible implications of our findings are discussed.

Monoamine oxidase inhibitors potentiate phenylethylamine effects in rhesus monkeys.

Acute pretreatment with either a Type A monoamine oxidase inhibitor (MAOI), clorgyline, or a Type B MAOI, pargyline, markedly reduced the dose of phenylethylamine (PEA) required to produce checking and a variety of other behavioral changes in rhesus monkeys. Doses of PEA (5 or 10 mg/kg) which previously were without effect, now produced significant behavioral changes in pretreatment animals.