Chemometrics in forensic chemistry - Part II: Standardized applications - Three examples involving illicit drugs.

In the recently published article "Chemometrics in forensic chemistry - Part I: Implications to the forensic workflow" the application of chemometric methods in forensic casework was described. The steps to facilitate standardized chemometric procedures and the availability of chemometric tools such as software and a guideline are under development. Three examples of typical illicit drugs casework, wherein chemometric methods were applied, are presented in the current paper. The kind of questions presented in these examples cover identification, classification, comparison and quantification of illicit drugs. The examples include several types of data (low- or high-dimensional), pre-processing and chemometric analyses that are applied to answer the questions presented. The performance measures for the chemometric methods are described based on separate datasets for training and testing (validation) purposes. In this way it is illustrated how a chemometric method is set up and data analysis may be performed. The presented methods are intended to be easily translatable to questions in forensic chemistry that are not drug-related.

Chemometrics in forensic chemistry - Part I: Implications to the forensic workflow.

The forensic literature shows a clear trend towards increasing use of chemometrics (i.e. multivariate analysis and other statistical methods). This can be seen in different disciplines such as drug profiling, arson debris analysis, spectral imaging, glass analysis, age determination, and more. In particular, current chemometric applications cover low-dimensional (e.g. drug impurity profiles) and high-dimensional data (e.g. Infrared and Raman spectra) and are therefore useful in many forensic disciplines. There is a dominant and increasing need in forensic chemistry for reliable and structured processing and interpretation of analytical data. This is especially true when classification (grouping) or profiling (batch comparison) is of interest. Chemometrics can provide additional information in complex crime cases and enhance productivity by improving the processes of data handling and interpretation in various applications. However, the use of chemometrics in everyday work tasks is often considered demanding by forensic scientists and, consequently, they are only reluctantly used. This article and following planned contributions are dedicated to those forensic chemists, interested in applying chemometrics but for any reasons are limited in the proper application of statistical tools - usually made for professionals - or the direct support of statisticians. Without claiming to be comprehensive, the literature reviewed revealed a sufficient overview towards the preferably used data handling and chemometric methods used to answer the forensic question. With this basis, a software tool will be designed (part of the EU project STEFA-G02) and handed out to forensic chemist with all necessary elements of data handling and evaluation. Because practical casework is less and less accompanied from the beginning to the end out of the same hand, more and more interfaces are built in through specialization of individuals. This article presents key influencing elements in the forensic workflow related to the most meaningful chemometric application and evaluation.

Two novel CLN6 mutations in variant late-infantile neuronal ceroid lipofuscinosis patients of Turkish origin.

Neuronal ceroid lipofuscinoses (NCLs) are the most common neurodegenerative childhood-onset disorders characterized by autosomal recessive inheritance, epileptic seizures, progressive psychomotor deterioration, visual failure, and premature death. At least seven subtypes of childhood-onset NCLs have been identified of which the late-infantile-onset forms (LINCLs) are genetically the most heterogeneous with four underlying genes identified. A variant form of LINCL (vLINCL) present in Turkish patients has been considered a distinct clinical and genetic entity (CLN7). However, we recently showed that mutations in the CLN8 gene account for a subset of Turkish vLINCL. Toward identifying the CLN7 gene we here screened the known NCL loci for homozygosity in nine Turkish vLINCL families. These loci were excluded in seven families that are likely to represent the 'true' Turkish vLINCL. In two families, we identified two novel homozygous mutations in the CLN6 gene: an intronic base substitution (c.542+5G>T) affecting the splicing of the transcript and a nonsense mutation (c.663C>G) creating a stop codon at tyrosine 221. These data indicate that CLN6 mutations, in addition to those of CLN8, should be considered a diagnostic alternative in Turkish vLINCL patients. The genetic background of the 'true' Turkish vLINCL, CLN7, remains to be defined.

New mutations in the neuronal ceroid lipofuscinosis genes.

Thirty-eight mutations and seven polymorphisms have recently been reported in the genes underlying the neuronal ceroid lipofuscinoses (NCLs) including 11 new mutations described here. A total of 114 mutations and 28 polymorphisms have now been described in the five human genes identified which cause NCL. Thirty-eight mutations are recorded for CLN1/PPT; 40 for CLN2/TTP-1, 31 for CLN3, four for CLN5, one for CLN8. Two mutations have been described in animal genes (cln8/mnd, CTSD). All mutations in NCL genes are contained in the NCL Mutation Database (http://www.ucl.ac.uk/NCL).

Neuronal trafficking of palmitoyl protein thioesterase provides an excellent model to study the effects of different mutations which cause infantile neuronal ceroid lipofuscinocis.

Infantile neuronal ceroid lipofuscinosis (INCL) is a severe neurodegenerative storage disorder in children caused by mutations in the palmitoyl protein thioesterase gene (PPT1). We have investigated here four naturally occurring previously described PPT1 mutations and show that all cause severe effects on PPT1 enzyme activity in transiently transfected COS-1 cells. Two of the mutations (delPhe84 and insCys45) cause a classical INCL phenotype and two (Thr75Pro and Leu219Gln) result in a late onset disease phenotype. All these mutated PPT1 molecules have severely altered intracellular localization in transiently transfected BHK-cells, whereas in mouse primary neuron cultures different effects were observed. In neurons the delPhe84 and insCys45 mutant polypeptides were targeted to the ER. Interestingly the Thr75Pro and Leu219Gln mutations had only minor effects on the neuronal trafficking of PPT1 and the mutated polypeptides were observed in neuronal shafts and showed colocalization with the presynaptic marker SV2. Our data indicates that neuronal cells provide an excellent model to study the genotype-phenotype correlation in INCL.

CLN-1 and CLN-5, genes for infantile and variant late infantile neuronal ceroid lipofuscinoses, are expressed in the embryonic human brain.

Mutations in the CLN-1 and CLN-5 genes underlie the infantile, and Finnish variant of the late-infantile, neuronal ceroid lipofuscinoses, respectively. These disorders are characterized by a massive neuronal death early in childhood. We have studied mRNA and protein expression of CLN-1 and CLN-5 in embryonic human brains. The spatial and temporal distributions of CLN-1 and CLN-5 were similar in the embryonic human brain. Both genes are expressed at the beginning of cortical neurogenesis, and this expression increases as cortical development proceeds. In the developing cortical plate, expression is found in postmitotic migrating neuroblasts and neuroblasts that have completed migration. Expression was intense also in cells of the thalamus as well as in the future Purkinje cell layer of the cerebellum. These findings indicate that expression of CLN-1 and CLN-5 may be significant for development of a wide range of maturating neurons.

Detection of eight novel palmitoyl protein thioesterase (PPT) mutations underlying infantile neuronal ceroid lipofuscinosis (INCL;CLN1).

The infantile form of neuronal ceroid lipofuscinosis (INCL; CLN1) is the earliest onset form of the neuronal ceroid lipofuscinoses (NCL), a group of progressive encephalopathies of children. INCL is caused by mutations in the palmitoyl protein thioesterase (PPT) gene, and we report here eight novel INCL mutations in PPT. Five of the mutations, c.456C>A, c.162-163insA, c.174-175delG, c.774-775insA, and a splice acceptor mutation IVS1-2A>G in intron 1, caused the generation of a premature STOP codon either directly or after a frameshift. One mutation was a three-bp insertion in exon 2 (c. 132-133insTGT) leading to insertion of one extra cysteine (Ser44-insCys-Cys45), and another mutation, a 3-bp deletion in exon 3 (c.249-251delCTT), led to deletion of Phe84 in PPT. A splice acceptor mutation IVS6-1G>T in intron 6 can be predicted to cause skipping of exon 7 in PPT. All of these novel mutations were associated with the classical phenotype of INCL, with the first symptoms starting around 12 months of age. The severe phenotypes could be explained by the nature of the novel mutations: five are predicted to lead to premature translational termination, thus abolishing the active site of PPT, and three will probably cause a misfolding of the nascent polypeptide. Thirty-five percent (7/20) of the disease alleles in these 11 families contained the most prevalent c.451C>T missense mutation outside Finland [Das et al., 1998]. Consequently, 31 different mutations underlying INCL have been found so far, the majority leading to classical INCL.

Reversible posterior leukoencephalopathy after combination chemotherapy.

We describe a young woman with Burkitt's lymphoma, treated with intravenous adriamycine and cyclophosphamide and intrathecal cytarabine. She developed a reversible posterior leukoencephalopathy syndrome (RPLS) with typical MRI findings. Diffusion-weighted images during the first days after the onset of symptoms predicted a small irreversible lesion in the frontal lobe, verified on T2-weighted images 1 month later. The patient showed full recovery after high-dose steroid treatment.

Trazodone in burning mouth pain: a placebo-controlled, double-blind study.

AIMS: An 8-week parallel, placebo-controlled, double-blind trial evaluated the efficacy of the antidepressant trazodone in the treatment of chronic burning mouth pain. METHODS: Thirty-seven carefully selected women aged 39 to 71 (mean 58.6 years) were randomized to receive either 200 mg of trazodone or a placebo in a similar manner. Pain and pain-related symptoms were evaluated on a visual analogue scale and other measures at 0, 2, 4, and 8 weeks. RESULTS: There were no significant differences between the groups in treatment effects for pain or pain-related symptoms. Seven patients in the trazodone group and 2 in the placebo group failed to complete the trial because of side effects. The most common side effects were dizziness and drowsiness. CONCLUSION: In this controlled trial, trazodone failed to relieve burning mouth pain.

Mouse palmitoyl protein thioesterase: gene structure and expression of cDNA.

Palmitoyl protein thioesterase (PPT) is the defective enzyme in infantile neuronal ceroid lipofuscinosis (INCL), which is a recessively inherited, progressive neurodegenerative disorder. We present here the cloning, chromosomal mapping, genomic structure, and the expression of the cDNA of mouse PPT. The mouse PPT gene spans >21 kb of genomic DNA and contains nine exons with a coding sequence of 918 bp. Fluorescence in situ hybridization to metaphase chromosomes localized the mouse PPT gene to the chromosome 4 conserved syntenic region with human chromosome 1p32 where the human PPT is located. PPT is expressed widely in a variety of mouse tissues. The mouse PPT cDNA is conserved highly with the human and rat PPT both at the nucleotide and amino acid sequence level. Transient expression of mouse PPT in COS-1 cells yielded a 38/36-kD differentially glycosylated polypeptide that was also secreted into culture media. Immunofluorescence analysis of transiently transfected HeLa cells indicated lysosomal localization of mouse PPT. Based on the high conservation of the gene and polypeptide structure as well as similar processing and intracellular localization, the function of PPT in mouse and human are likely to be very similar.

New mothers' experiences of postpartum care--a phenomenological follow-up study.

The aim of this study is to explore and describe the new mother's experiences of postpartum care. It is part of an ongoing clinical longitudinal research project studying experiences of health, suffering and care and the organizational culture of Finnish maternity care. Postpartum care is seldom either technological or dramatic and has been shown to take low priority in both practice and research. This article uses the theoretical perspective of Eriksson as a basis for discussing insights gained from the phenomenological study. Nine women were interviewed at the end of their pregnancy, and 3 weeks, 3 months and 21/2 years after giving birth. The research approach was that of Colaizzi, which has its roots in phenomenological philosophy, and which attempts to present accurately the lived experiences of those studied. Data suggest that the transitional process from being an expectant mother to being a new mother occurs slowly but intensely in a unique way during the first days after the baby is born. The new mother experiences caring communion in sharing her life situation with the midwife, learning directly through the midwife's teaching and indirectly when the midwife enables her to be in peace and quiet together with her baby and family. Other new mothers are caring towards the woman reciprocally, sharing the same situation, helping one another and learning together. Three challenges in postpartum care emerge from this study. These are to understand the meaning of caring, to involve family and other new mothers more consciously, and to see the woman as a new mother who needs both to care and be cared for both by her family and friends and by professional carers.

Effects of xylitol, xylitol-sorbitol, and placebo chewing gums on the plaque of habitual xylitol consumers.

Xylitol reduces plaque but the reduction mechanism is largely unknown. The main aim of the present study was to determine whether the xylitol-induced reduction in the amount of plaque and the number of mutans streptococci could be demonstrated in subjects with (presumably) high levels of xylitol-resistant (XR; not inhibited by xylitol) mutans streptococci acquired following previous xylitol consumptions. 37 healthy dental students participated in the double-blind study. All subjects had been uncontrolled, habitual consumers of xylitol-containing products for at least 1 yr before the study. A 1-month washout period was followed by a 2-week test period during which either xylitol, xylitol-sorbitol or unsweetened chewing gum base was chewed 3-5 x a day. Plaque and saliva samples were collected at baseline and at the 2-week point for determination of the amount of plaque, microbiological variables, and hydrolytic enzymes. Mixtures of xylitol and sorbitol seemed to perform equally well with respect to reduction in the amount of plaque but not the number of mutans streptococci. Thus, polyols were the active ingredients of chewing gums able to modulate the amount of plaque and its microbial composition. Xylitol reduced plaque with a mechanism which appeared not to be associated with the study-induced changes in the proportion (%) of mutans streptococci in plaque, the number of salivary mutans streptococci, the proportion of XR strains in plaque or saliva, or the hydrolytic enzyme activities of plaque.

Monoamine oxidase B inhibitor selegiline protects young and aged rat peripheral sympathetic neurons against 6-hydroxydopamine-induced neurotoxicity.

Selegiline is a selective and irreversible monoamine B inhibitor with the capacity to increase the level of several antioxidative enzymes in rat brain. It can protect adrenergic neurons against injury induced by neurotoxins such as MPTP, DSP-4 and AF64A in animal studies. In addition, the protective action is not limited to catecholaminergic cells, as selegiline can also minimize the loss of developing motoneurons after axotomy. The aim of this study was to determine whether selegiline can protect peripheral catecholaminergic neurons against the neurotoxic effect of 6-OHDA. This kind of protective effect against 6-OHDA neurotoxicity has not been reported before. Wistar albino male rats aged 4 or 24 months were treated with selegiline or saline solution 1 h before 6-OHDA injection. At 2 weeks after the 6-OHDA injection, the superior cervical ganglia (SCG) and submandibular glands (SMG) were studied using catecholamine histofluorescence and immunohistochemistry for tyrosine hydroxylase (TH). The number of TH-positive cells in the SCG and the length and number of adrenergic nerve fibers in the SMG were quantified. Our findings showed that 6-OHDA caused a reduction of TH immunoreactivity and catecholamine histofluorescence in neuronal somata, as well as a decrease in the number and length of adrenergic nerve fibers in the submandibular gland. Selegiline pretreatment protected SCG neurons and their postganglionic nerve fibers in SMG against these changes in a dose-dependent manner. The mechanism through which selegiline exerts its neuroprotective effect is as yet unknown.

Protein composition, adhesion, and agglutination properties of saliva in burning mouth syndrome.

Resting and stimulated whole saliva and parotid saliva of men and pre- and post-menopausal women with burning mouth syndrome (BMS) and their matched controls were studied. Women with BMS had slightly, but not significantly, higher flow rates than their controls. The total protein concentration in stimulated saliva of women with BMS was significantly lower than that of controls. This difference was not associated with the flow rate. The proportional amount of sialic acid, used as an indicator of mucin concentration, was higher in subjects with BMS than in their controls. SDS-PAGE showed no consistent differences in the protein profiles of saliva, nor were any differences observed in the adhesion or agglutination assays between subjects with BMS and their matched controls. Thus, the present results indicate that BMS is not associated with a decrease in the protecting and lubricating properties of saliva.

Burning mouth in a Finnish adult population.

Burning mouth syndrome is an oral pain disorder with a prevalence of 5-18% in patient materials. The aim of this study was to determine the prevalence of Burning mouth syndrome in a representative sample of the general adult population. Altogether 431 subjects (237 females, 194 males) participated in the study. Subjects were questioned about the experience of prolonged burning sensation; the site, severity, pattern, duration and possible associations of the onset of the burning sensation, and a thorough clinical examination was performed. In all, 15% of the subjects had experienced prolonged oral burning but a half of them had some clinically observable oral mucosal lesion or oral candidosis. The prevalence of the complaint was significantly higher in females than in males.

Childhood cancer and parental occupation in Finland.

A case-control study was conducted of the occupations of parents of children under 15 with diagnosed malignancies. The total series contained all childhood cancers cases reported to the Finnish Cancer Registry during the period 1959-75. The parental occupations, recorded at the time of pregnancy, were collected from maternity welfare centres. The cases were analysed as a singly group or as subgroups according to the diagnoses-brain tumours, leukaemia, and all other malignancies. The maternal occupations found more frequently among cases than controls included farmers' wives (1959-68 only), pharmacists, saleswomen, bakers, and factory work of an vehicle driving, machine repair, painting, and the work of men who gave an academic degree as their occupation. Some of these occupations involve possible exposure to harmful chemicals, although chance correlations cannot be excluded.

Transplacental carcinogens and mutagens: childhood cancer, malformations, and abortions as risk indicators.

Childhood cancer, malformations, and spontaneous abortions in Finland were analyzed according to the parents' occupations. Children of women working in the food industry and farming and of men working in motor vehicle driving and farming appeared to have an elevated risk of cancer. Women in industrial and construction occupations had an increased risk of having malformed children and spontaneous abortions.