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PubMed1998

Rapid trisomy diagnosis (21, 18, and 13) using fluorescent PCR and short tandem repeats: applications for prenatal diagnosis and preimplantation genetic diagnosis.

PURPOSE AND METHODS: Prenatal diagnosis of fetal trisomies is usually performed by cytogenetic analysis from amniotic fluid. This requires lengthy laboratory procedures and high costs and is unsuitable for large-scale screening of pregnant women. An alternative method, which is rapid and inexpensive and may potentially be suitable for diagnosing trisomies even from single fetal cells, is the fluorescent polymerase chain reaction (F-PCR) using polymorphic small tandem repeats (STRs). RESULTS: In this paper we present data demonstrating that fluorescent PCR amplification of STRs can be used for rapid diagnosis of trisomy 21, trisomy 18, and trisomy 13 and can be successfully applied to both prenatal diagnosis and diagnosis of single cells. This study also reports significant numbers of prenatal diagnoses using quantitative fluorescent PCR. CONCLUSIONS: We believe that further studies of greater numbers of samples will determine the absolute reliability of this technique. These results also provide a model for trisomy diagnosis from single cells using multiple STR markers for either preimplantation genetic diagnosis or, potentially, diagnosis from fetal cells isolated from maternal blood.

Chromosomes, Human↗

PubMed1997

Yohimbine, erectile capacity, and sexual response in men.

In a double-blind, placebo-controlled crossover study on a group of men with erectile problems and a sexually functional comparison group, the effect of yohimbine (up to 30 mg/day) was assessed on a number of objective and subjective measures of erectile response through the use of daily logs and psychophysiological laboratory procedures involving response to visual sexual stimulation (VSS). Sexual desire, arousal, and ejaculatory response were also assessed. Results indicated no effect of yohimbine on most aspects of sexual response in sexually functional men. Mixed effects were found on measures of sexual function in men erectile dysfunction, with 3 of 11 men reporting strong positive effects. Under yohimbine, frequency of sexual activities increased, as did self-assessed genital response to VSS. Daily diaries indicated increased sexual arousal and erectile response during masturbation but not intercourse. A number of other measures, including NPT and retrospective summaries of erectile functioning at the end of drug phases, showed no effect. Results are discussed in terms of possible yohimbic effects on psychological factors that modulate overall sexual response, and consequently, erectile response.

Adult↗

PubMed2004

A slaughter slab survey for extra-intestinal porcine helminth infections in northern Tanzania.

A survey on extra-intestinal porcine helminths was conducted at three slaughter slabs that receive pigs from Mbulu, a district endemic for porcine cysticercosis in northern Tanzania. Seventy carcases of pigs between 1 and 2 years old were examined between December 1997 and March 1998. The examination involved ante-mortem lingual examination for Taenia solium cysticercosis followed by post-mortem inspection. In addition, a laboratory procedure was performed to determine whether any of these domestic pigs were infected with Trichinella species. Parasites detected were Ascaris suum (44.3%), Echinococcus granulosus (4.3%) and Taenia hydatigena (1.4%). The lack of cases of porcine cysticercosis in this study compared to previous studies suggests that pig traders are conducting their own ante-mortem lingual examinations before purchasing pigs in the rural communities where the parasite is still highly prevalent. It is concluded that improved meat inspection could prove useful in reducing the local population's risk of infection with these parasites. The results of this study have revealed the parasites of agricultral and public health importance in the targeted communities. Further epidemiological investigations are required to better determine parasite prevalence and impact in order to formulate appropriate and cost-effective strategies for control.

Abattoirs↗

PubMed2002

[Transmissible spongiform encephalopathies in sheep and goats].

Scrapie has been known to occur in sheep and goats for over 250 years. Sheep and goats can be experimentally infected orally with BSE, however BSE infection can only be distinguished from scrapie using costly and extensive laboratory procedures. An overview of both the current state of knowledge on Transmissible Spongiform Encephalopathies (TSE) in small ruminants as well as the TSE monitoring and control strategies in place in Switzerland is presented.

Animals↗

PubMed2003

[Modern methods of virus diagnosis].

In recent years, a series of new approaches for the laboratory diagnosis of viral infections have been developed. In the present review, we describe the different tests available, such as virus isolation and identification in cell culture, antigen and genome detection, and determination of antibodies by serological methods. In order to chose the appropriate test for a given case, advantages and disadvantages of the laboratory procedures as well as their suitability for specimens taken from different organs have to be taken into account. Such considerations are particularly important for a correct interpretation of the results.

Antibodies, Viral↗

PubMed2000

A prospective economic evaluation of basiliximab (Simulect) therapy following renal transplantation.

BACKGROUND: Immunoprophylaxis with basiliximab (Simulect), an anti-interleukin-2-receptor (anti-IL-2R; CD25) chimeric monoclonal antibody, has been demonstrated to significantly reduce the incidence of acute cellular rejection in adult renal allograft recipients (32% vs. placebo, p < 0.01). METHODS: An economic evaluation was conducted as part of a U.S. multi-center, randomized, double-blind, placebo-controlled clinical trial comparing basiliximab plus dual immunosuppressive therapy (cyclosporine modified [Neoral] and corticosteroids) to dual therapy alone. Healthcare resources utilized by the 346 subjects in the 'intent-to-treat' population were prospectively collected over the 1-yr study period. Direct medical costs were determined for all hospitalizations, outpatient provider visits, procedures (excluding the initial transplant procedure), laboratory and diagnostic tests, and immunosuppressants, including basiliximab when administered. RESULTS: Total first-year medical costs were lower for the basiliximab group than for the placebo group ($28 927 vs. $32 300, difference = $3373). although this difference was not statistically significant. First-year hospital costs for treating acute rejection were also lower for the basiliximab group ($9328 vs. $10761, difference = $1433); however, this difference did not achieve statistical significance. Importantly, the efficacy analysis demonstrated a significant reduction in the incidence of acute rejection (38 vs. 55%, p < 0.01) in the basiliximab arm, and this was accomplished without increasing the overall cost of care. Fewer basiliximab-treated patients (8 vs. 15%,, p = 0.03) were hospitalized. This observation suggested less serious illness and reduced treatment costs among basiliximab-treated patients, because the overall incidence of infection was similar between the groups. The adverse event profile of patients receiving basiliximab was clinically and economically indistinguishable from that of those treated with placebo. CONCLUSION: Induction immunosuppression with basiliximab, combined with cyclosporine modified and corticosteroids, was therapeutically beneficial and contained medical costs during the initial post-transplant year.

Adrenal Cortex Hormones↗

PubMed2002

HER2/neu expression in adenoid cystic carcinoma of salivary gland origin: an immunohistochemical study.

BACKGROUND: Adenoid cystic carcinoma (ACC) is a malignant tumor of salivary gland origin, which is characterized by a high rate of local recurrence and distant hematogenous metastasis. Despite aggressive surgical treatment and radiotherapy, the patient's long-term prognosis is dismal. Prompted by recent studies on the amplification of the oncogene HER2/neu in salivary gland tumors, we analyzed the immunohistochemical overexpression of HER2/neu in salivary glands ACC. If the tumor exhibits overexpression of HER2/neu, then treating it with the anti-HER2/neu therapeutic agent, Herceptin (Trastuzumab, Genentech, CA), could be considered. METHODS: The study comprised of 32 samples of formalin-fixed, paraffin-embedded specimens. All laboratory procedures and scoring criteria were performed according to currently approved FDA methods. RESULTS: HER2/neu overexpression was found in only five (16%) cases. Four cases (13%) scored 1+ and one case (3%) scored 2+. CONCLUSIONS: The low prevalence of HER2/neu overexpression in ACC limits the clinical utility of Herceptin therapy for salivary gland ACC.

Adult↗

PubMed1997

Maternal sensitivity in a developing society: the context of urban poverty and infant chronic undernutrition.

This study focuses on young children's chronic undernutrition and its association with maternal sensitivity, sociodemographic variables, children's play, and problem-solving measures. Data were obtained with home observations and laboratory procedures on 85 mothers and infants (M age = 18 months) in a low-income urban population in Santiago, Chile. Maternal sensitivity was correlated with maternal education, maternal weight, and marital satisfaction. Observed in a variety of maternal roles, maternal sensitivity was also significantly associated with children's nutritional status, attachment security, and mastery behavior. These findings demonstrate the relevance of the maternal sensitivity construct outside industrialized societies and underline the need for intervention strategies to extend beyond nutritional supplementation to address deficits of maternal care associated with specific caregiver's roles.

Adult↗

PubMed1998

Production of emotional facial expressions in European American, Japanese, and Chinese infants.

European American, Japanese, and Chinese 11-month-olds participated in emotion-inducing laboratory procedures. Facial responses were scored with BabyFACS, an anatomically based coding system. Overall, Chinese infants were less expressive than European American and Japanese infants. On measures of smiling and crying, Chinese infants scored lower than European American infants, whereas Japanese infants were similar to the European American infants or fell between the two other groups. Results suggest that differences in expressivity between European American and Chinese infants are more robust than those between European American and Japanese infants and that Chinese and Japanese infants can differ significantly. Cross-cultural differences were also found for some specific brow, cheek, and midface facial actions (e.g., brows lowered). These are discussed in terms of current controversies about infant affective facial expressions.

Child, Preschool↗

PubMed2003

Emotional convergence between people over time.

The authors propose that people in relationships become emotionally similar over time--as this similarity would help coordinate the thoughts and behaviors of the relationship partners, increase their mutual understanding, and foster their social cohesion. Using laboratory procedures to induce and assess emotional response, the authors found that dating partners (Study 1) and college roommates (Studies 2 and 3) became more similar in their emotional responses over the course of a year. Further, relationship partners with less power made more of the change necessary for convergence to occur. Consistent with the proposed benefits of emotional similarity, relationships whose partners were more emotionally similar were more cohesive and less likely to dissolve. Discussion focuses on implications of emotional convergence and on potential mechanisms.

Adolescent↗

PubMed1983

Immunological stability of an elapid venom, Tropidechis carinatus, and its relevance to the clinical detection of snake venom.

Using immunological techniques, cases of human snake-bite can be proven and individual snake species identified. A series of experiments is described, to test the antigenic stability and physical properties of an Elapid venom, venom properties which will have implications in field use, transport, or the laboratory procedures relating to the immunological characterization of Australian snake venoms. Using venom from the Elapid, Tropidechis carinatus, we have demonstrated significant immunological stability at a temperature of 37 degrees for 48 h at least, and for 24 h at least when incubated continuously with skin, muscle, and fat homogenates; the venom is stable at 56 degrees for 2 h at least. No loss of venom occurs over the pH range 7-10; at pH ranges less than 4 and at ranges greater than 10 only 30% of venom is detected after 30 min incubation. Sonication (10 min at 100 watts) does not destroy immunological properties of the venom; 10 freeze-thaw cycles result in some 9% loss of immunologically detectable activity. Venom is adsorbed significantly on to dacron swabs, only 13% of the applied does being detected after 48 h incubation at 28 degrees. Sixty-seven percent of applied venom can be recovered from the skin of human volunteers 6 h after a simulated bite. The venom of this Elapid is antigenically robust. With the currently available sensitive assays, venom from human skin should still be detected in material kept without special preparation under field conditions for up to 2 days at least.

Animals↗

PubMed2005

Engineering novel binding proteins from nonimmunoglobulin domains.

Not all adaptive immune systems use the immunoglobulin fold as the basis for specific recognition molecules: sea lampreys, for example, have evolved an adaptive immune system that is based on leucine-rich repeat proteins. Additionally, many other proteins, not necessarily involved in adaptive immunity, mediate specific high-affinity interactions. Such alternatives to immunoglobulins represent attractive starting points for the design of novel binding molecules for research and clinical applications. Indeed, through progress and increased experience in library design and selection technologies, gained not least from working with synthetic antibody libraries, researchers have now exploited many of these novel scaffolds as tailor-made affinity reagents. Significant progress has been made not only in the basic science of generating specific binding molecules, but also in applications of the selected binders in laboratory procedures, proteomics, diagnostics and therapy. Challenges ahead include identifying applications where these novel proteins can not only be an alternative, but can enable approaches so far deemed technically impossible, and delineate those therapeutic applications commensurate with the molecular properties of the respective proteins.

Binding Sites↗

PubMed2006

Parasitic infections in transplant recipients.

Parasitic infections are important complications of organ transplantation that are often overlooked in the differential diagnosis of post-transplantation pyrexial illness. Although their frequency is unknown, they seem to be much less prevalent than bacterial and viral infections. Only 5% of human pathogenic parasites have been reported to cause significant illness in transplant recipients. Infection can occur via transmission with the graft or blood transfusion, or be acquired de novo from the environment. Recrudescence of dormant infection can lead to active disease. Post-transplantation parasitic disorders tend to cluster into two clinical profiles. First, an acute systemic illness with anemia, constitutional manifestations and variable stigmata of organ involvement; acute graft dysfunction can lead to confusion and acute rejection. Protozoa including malarial Plasmodium, Leishmania, Trypanosoma and Toxoplasma are associated with this profile. The second typical manifestation encompasses a few localized syndromes, usually associated with the lower gastrointestinal tract, caused by either protozoa (Cryptosporidium and microsporidia) or nematodes (Strongyloides and Ascaris). Dissemination of localized infections can lead to life-threatening systemic manifestations. A high index of suspicion is essential, as diagnosis requires special sampling techniques and laboratory procedures. Definitive diagnosis is usually achieved by detecting the parasite in the patient's tissues or body fluids by histological examination or culture, or by polymerase chain reaction amplification of the parasite-specific antigen sequence. Antibody detection using serological techniques is also possible in a few parasitic infections. Certain lesions have characteristic radiological appearances, hence the value of imaging, particularly in the cerebral syndromes. Treatment is usually straightforward (broad spectrum or specific drugs), yet some species are drug resistant.

Animals↗

PubMed2000

Intrapair resemblance in very low calorie diet-induced weight loss in female obese identical twins.

OBJECTIVE: To assess intrapair resemblance in changes of body weight, total body fat, fat distribution, resting metabolic rate, fasting respiratory quotient and cardiovascular disease risk factors in response to therapeutic weight loss in female obese identical twins. DESIGN: Patients stayed for 40 days on an inpatient metabolic unit under careful supervision. The stay was divided into three parts: an initial period of 7 days for adjustment to the hospital environment and for baseline measurements, 28 days of the weight reduction regimen when negative energy balance was achieved mainly by a very low calorie diet (1.6 MJ per day) and 5 days of testing after weight reduction. SUBJECTS: Fourteen pairs of premenopausal female obese identical twins (age: 39.0+/-1.7 y; body weight (BW): 93.9+/-21.2 kg; body mass index (BMI): 34.2+/-7.8 kg/m2) participated in the study. MEASUREMENTS: Before and after weight loss, the following measurements were made: body composition by anthropometry and hydrodensitometry, intra-abdominal fat by ultrasonography, resting metabolic rate by indirect calorimetry. Total cholesterol, high-density lipoprotein-cholesterol, triglycerides and uric acid were determined by standard laboratory procedures. Blood pressure was measured in the morning in the recumbent position. RESULTS: Subjects lost 8.8+/-1.9 kg of weight, from 93.9+/-21.2 to 85.1+/-10.9 kg (P<0.0001) and 6.5+/-2.3 kg of body fat (P<0.001). Weight losses varied widely among subjects, with a high correlation between losses of members of twin pairs for body weight (r=0.85; P<0.001) and for body fat (r=0.88; P<0.0001). Changes in uric acid resulting from weight loss were also correlated among members of twin pairs whereas changes in blood pressure, cholesterol and triglycerides were not. CONCLUSION: The great intrapair resemblance observed in very low calorie diet-induced weight and fat losses in female obese identical twins suggests an important role of genetic factors in response to the weight reduction regimen.

Adipose Tissue↗

PubMed2002

Further evidence for the role of the dopamine D4 receptor (DRD4) gene in attachment disorganization: interaction of the exon III 48-bp repeat and the -521 C/T promoter polymorphisms.

In non-clinical low-risk populations 15% of infants show disorganized attachment behavior(1,2) with their caregivers in the Strange Situation,(3) a mildly stressful laboratory procedure testing infants' ability to cope with separation anxiety. Disorganization of early attachment has been primarily ascribed to inadequate parenting,(2,4,5) and has been associated with childhood behavior problems(6,7)and adolescent psychopathological tendencies.(5) We have recently reported an association between the DRD4 exon III 48 basepair repeat polymorphism and disorganization of infants' attachment behavior towards their mother in a low-social-risk group of 1-year-old infants:(8) the risk for disorganized attachment among infants carrying the 7-repeat allele was fourfold. Here we report further evidence for the involvement of the dopamine D4 receptor gene in attachment disorganization. The same group of infants was genotyped for the functional -521 C/T single nucleotide polymorphism (SNP) in the upstream regulatory region of the DRD4 gene(9) in order to test the association with attachment disorganization both alone and in interaction with the DRD4 exon III 7-repeat allele. While the -521 C/T genotype itself had no effect on attachment status (chi(2) = 0.41, df = 2, P = 0.82), there was an interaction between the structural 48-bp repeat polymorphism and the -521 C/T promoter polymorphism: the association between disorganized attachment and the 7-repeat allele was enhanced in the presence of the -521 T allele (chi(2) = 6.61 and 6.67, df = 1, P < 0.025 for CT and TT genotypes, respectively). In the presence of both risk alleles the odds ratio for disorganized attachment increased tenfold. This result supports our previous postulation that the DRD4 gene plays a role in the development of attachment behavior in low-risk, non-clinical populations.

Alleles↗

PubMed2002

Immunological research in clinical psychiatry: report on the consensus debate during the 7th Expert Meeting on Psychiatry and Immunology.

There is convincing evidence that cytokines are involved in the physiology and pathophysiology of brain function and interact with different neurotransmitter and neuroendocrine pathways. The possible involvement of the immune system in the neurobiological mechanisms that underlie psychiatric disorders has attracted increasing attention in recent years. Thus in the last decade, numerous clinical studies have demonstrated dysregulated immune functions in patients with psychiatric disorders. Such findings formed the basis of the 7th Expert Meeting on Psychiatry and Immunology in Muenster, Germany, where a consensus symposium was held to consider the strengths and weaknesses of current research in psychoneuroimmunology. Following a general overview of the field, the following topics were discussed: (1) methodological problems in laboratory procedures and recruitment of clinical samples; (2) the importance of pre-clinical research and animal models in psychiatric research; (3) the problem of statistical vs biological relevance. It was concluded that, despite a fruitful proliferation of research activities throughout the last decade, the continuous elaboration of methodological standards including the implementation of hypothesis-driven research represents a task that is likely to prove crucial for the future development of immunology research in clinical psychiatry.

Allergy and Immunology↗

PubMed2004

Use of polymorphisms in the noncoding region of the human mitochondrial genome to identify potential contamination of human leukemia-lymphoma cell lines.

The availability of the complete sequence of human mitochondrial DNA (mtDNA) has proven extremely useful in phylogenetic studies, forensic science and the determination of chimerism after allogeneic stem cell transplantation. In this study, we could demonstrate that the analysis of mtDNA polymorphisms is a quick and reliable method to identify contamination of human hematopoietic cell lines. This assay is based on PCR-sequencing of three hypervariable segments of the control region of mtDNA (hypervariable region (HRV) 1, 2 and 3). All three regions contain a large number of single-base polymorphisms. mtDNA was isolated according to standard laboratory procedures and amplified by PCR. Subsequently products were sequenced and evaluated with a semiautomated DNA sequencer system. So far, 21 human leukemia-lymphoma (LL) cell lines and nine other human cell lines were screened for contamination by other cell lines applying this method. We conclude that analysis of mtDNA polymorphisms is a quick, reliable and inexpensive method to detect intra - and interspecies cross-contamination and for the authentication of human LL cell lines. In comparison to other methods (cytogenetics, fluorescence in situ hybridization or immunophenotyping), this technique is less laborious and time consuming.

Cell Line, Tumor↗

PubMed1979

Deoxyribonucleic acid synthesis in isolated nuclei from baby-hamster kidney cells (BHK-21/C13). Characterization of the system.

A comparative study of some commonly employed laboratory procedures for studying DNA synthesis in isolated nuclei was carried out. Nuclei isolated from baby-hamster kidney (BHK-21/C13) cells synthesize DNA for 30-60min at 37 degrees C in a reaction requiring uni- and bi-valent cations, ATP and all four deoxyribonucleoside 5'-triphosphates. The addition of either ribonucleotides or cytosol from S-phase cells had no effect, but DNA synthesis was stimulated by some dextrans (mol.wt. 5x10(6)). The extent of synthesis was influenced by apparently minor variations in experimental conditions. For example, DNA synthesis by nuclei in Tris/HCl, pH7.5, was only 50% of that observed in Hepes/NaOH, pH7.5; the presence of detergents Triton X-100, Triton N-101, Nonidet P-40, Brij 58 and Tween 80 in the incubation medium altered the amount of synthesis to different extents. Although most detergents inhibited synthesis, a stimulation occurred with Tween 80 (150% of controls). These effects were reversed on washing the nuclei, except that of Brij 58, which inhibited DNA synthesis by 90-95% irreversibly. Anomalous sucrose-density-gradient sedimentation behaviour of the DNA, and of precursor [(3)H]-dTTP, was observed when nuclei were lysed with solutions of sodium dodecyl sulphate/Mg(2+) or with Sarkosyl/Mg(2+), but consistent results, showing that the DNA synthesized in vitro sedimented exclusively at about 4S, were obtained when nuclei were lysed with sodium dodecyl sulphate (without Mg(2+))/EDTA, digested with proteinase K and heated at 100 degrees C with 11% (v/v) formaldehyde to prevent macromolecular association. These results, coupled with density-labelling studies with bromodeoxyuridine and CsCl-density-gradient analysis, showed that DNA synthesis in these nuclei was replicative and was restricted to a covalent extension of Okazaki pieces previously initiated in vivo. No new initiations were observed, and the DNA was not ligated into larger molecules. The cessation of DNA synthesis after about 60 min was due to the complete utilization of available primer/template DNA.

Animals↗