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Biomedical subjects

M Peters

Publications and source records attributed to M Peters.

At least 55 records · Page 3Linked to original sources
PubMed2003

Pediatric venous thromboembolic disease in one single center: congenital prothrombotic disorders and the clinical outcome.

To learn more about the frequencies of congenital prothrombotic disorders in pediatric venous thromboembolism (VTE) and the outcome of this disease, we evaluated consecutive patients from 0 to 18 years with objectively diagnosed VTE at a single tertiary center over a 12-year period. We included 100 patients, with a median age at diagnosis of 1.0 year (range 2 days to 17 years). At least one underlying clinical condition was present in 96% of the patients. Factor (F)V G1691A mutation was present in 13%, FII G20210A mutation in 3%, antithrombin deficiency in 1%, protein C deficiency in 1% and protein S deficiency in 1% of the tested patients. Combined defects were present in 2.6% of the 77 patients with a complete work-up. Positive family history appeared to be the only predictor for positive testing for congenital disorders (OR 14.9, 95% CI 1.9-113). The overall mortality rate was 20%. The cumulative recurrence-free survival was 92% after 1 year of follow-up, and 82% after 7 years. The incidence and severity of the post-thrombotic syndrome was analyzed in a subgroup of 33 patients with VTE of the lower extremities. Twenty-three (70%) patients developed PTS: moderate in three and mild in 20 patients. In conclusion, congenital prothrombotic disorders seem to play a role in the development of pediatric VTE, and the risk of complications of this disease is high.

Adolescent↗
PubMed2003

Prenatal diagnosis of tetrasomy 18p using multiplex fluorescent PCR and comparison with a variety of techniques.

We report genetic characterization of isochromosome 18p using a combination of cytogenetic and molecular genetic methods, including multiplex fluorescent PCR. The patient was referred for chorionic villus sampling (CVS) due to advanced maternal age and maternal anxiety. The placental karyotype was 47,XX,+mar, with the marker having the appearance of a small supernumerary isochromosome. Because differentiating between isochromosomes and other structural rearrangements is normally very difficult, a variety of genetic tests including fluorescence in situ hybridization (FISH), PCR, and multiplex fluorescent PCR were undertaken to determine chromosomal origin and copy number and, thus, allow accurate diagnosis of the corresponding syndrome. FISH determined that the marker chromosome contained chromosome 18 material. PCR of a variety of short tandem repeats (STRs) confirmed that there was at least one extra copy of the maternal 18p material. However, neither FISH nor PCR could accurately determine copy number. Multiplex fluorescent PCR (MF-PCR) of STRs simultaneously determined that: (1) the marker included 18p material; (2) the marker was maternal in origin; (3) allele copy number indicated tetrasomy; and (4) contamination of the sample could be ruled out. Results were also rapid with accurate diagnosis of the syndrome tetrasomy 18p possible within 5 hours.

Adult↗
PubMed2003

Phase I and pharmacokinetic study of CCI-779, a novel cytostatic cell-cycle inhibitor, in combination with 5-fluorouracil and leucovorin in patients with advanced solid tumors.

BACKGROUND: CCI-779 is a novel ester of the immunosuppressive agent sirolimus that exerts cytostatic effects by the inhibition of the translation of cell-cycle regulatory proteins. We investigated the maximum tolerated dose (MTD) and pharmacokinetics (PK) of CCI-779 in combination with leucovorin (LV) and 5-fluorouracil (5-FU) in patients with advanced solid tumors. PATIENTS AND METHODS: Patients were treated with LV at 200 mg/m(2) as a 1-h i.v. infusion directly followed by continuous 24-h i.v. infusion of 5-FU, in the first patient at 2000 mg/m(2) and in subsequent patients at 2600 mg/m(2). CCI-779 was administered directly prior to LV as a 30-min i.v. infusion at a starting dose of 15 mg/m(2) beginning at day 8 and escalated in subsequent cohorts of patients. One cycle consisted of six weekly administrations followed by 1 week of rest. Blood samples were drawn to assess PK of CCI-779 as well as its effect on steady-state 5-FU exposures. RESULTS: Twenty-eight patients entered the study, the majority having tumor types for which 5-FU is used as a treatment. CCI-779 doses of 15, 25, 45 and 75 mg/m(2) were investigated. Skin toxicity (rash) was prominent at all dose levels examined. Stomatitis was the dose-limiting toxicity (DLT) for 75 mg/m(2) doses of CCI-779. Subsequently the cohort at 45 mg/m(2) was expanded to a total of 15 patients, and at this dose level two treatment-related deaths occurred due to mucositis with bowel perforation. Based on the toxicities observed, it was decided to discontinue the study. Partial responses were observed in three patients with gastrointestinal tumors. No pharmacokinetic interaction between CCI-779 and 5-FU was observed. CONCLUSIONS: The safety profiles of CCI-779 and 5-FU/LV suggest an overlap of drug-related toxicities, and the administration of these drugs at these doses and schedule resulted in unacceptable toxicity and therefore cannot be recommended. If CCI-779 is to be used in combination with 5-FU/LV, other doses or schedules of administration will need to be explored.

Adult↗
PubMed2003

"A deep fragrance of academia": the Australian Tobacco Research Foundation.

OBJECTIVES: (1) To review the history of the tobacco industry supported Australian Tobacco Research Foundation (ATRF)(1970-1994) for evidence of the industry's use of the Foundation to further its objectives that "more research was needed" on smoking and health and to promulgate the view that nicotine was not addictive. (2) To review efforts by public health advocates to discredit the ATRF as a public relations tool used by the Australian industry. METHODS: Systematic search of previously internal industry documents released through the US Master Settlement Agreement. RESULTS: The ATRF was headed by prestigious Australian medical scientists, with at least one considered by the industry to be "industry positive". An international ATRF symposium on nicotine was vetted by the industry and heavily attended by industry approved scientists. Following sustained criticism from the health and medical community about the industry's creation of the ATRF to further its objectives, the ATRF's scientific committee was provoked to publicly declare in 1988 that smoking was a causative agent in disease. This criticism led to growing ATRF boycotts by scientists and substandard applications, causing the industry to see the ATRF as being poor value-for-money and eventually abandoning it. CONCLUSIONS: The raison d'etre for the ATRF's establishment was to allow the Australian industry to point to its continuing commitment to independent medical research, with the implied corollary that tobacco control measures were premature in the face of insufficient evidence about tobacco's harms. Sustained criticism of tobacco industry funded research schemes can undermine their credibility among the scientific community.

Australia↗
PubMed2003

Osteogenesis imperfecta in two litters of dachshunds.

A clinical, morphologic, ultrastructural, and genetic study was performed on five rough-coated dachshund semisiblings with osteogenesis imperfecta (OI). Clinical signs consisted of pain, spontaneous bone and teeth fractures, joint hyperlaxity, and reduced bone density on radiography. Primary teeth were extremely thin-walled and brittle. The hallmark of the disease was a severe osteopenia characterized by impairment of lamellar bone formation in the long bones, skull, and vertebral column. No deformity or dwarfism was present. The columns of chondrocytes and primary trabeculae in the epiphyses and metaphyses were histologically normal. An abrupt failure of secondary spongiosa and lamellar bone formation was evident in the medullary and cortical zones in all animals. The few existing trabeculae consisted of woven bone. There was no increase in the number and size of osteoclasts or lacunae. In the teeth, the dentine layers were thin and lacked a tubular pattern. Ultrastructurally, osteoid apposition on bone surfaces was reduced, and small numbers of large cytoplasmic vacuoles were present in a few osteoblasts. Molecular analyses of the collagen type I-encoding genes COL1A1 and COL1A2 revealed several nucleotide differences compared with the published canine sequences but were not significant for OI. Therefore, OI in these Dachshund litters was characterized by a severe, generalized osteopenia and dentinopenia. This pattern of reduced bone formation is suggestive of defective production of collagen type I.

Animals↗
PubMed2003

[Bronchopneumonia and polyarthritis due to Mycoplasma bovis in a calf].

This case report describes gross lesions and histopathological findings in a 3-months-old calf originating from a feedlot with approximately 400 cattle. In this animal and additional 14 cattle of similar age, which were kept together in the same stable, swollen joints had occurred suddenly. The examination of this calf showed that a severe polyarthritis induced by haematogenous spread of Mycoplasma bovis following bronchopenumonia was present, which was characterised by necrotising lesions of the joint capsules and severe cartilage erosions.

Animals↗
PubMed2003

Haemophilia patients aged 0-18 years in the Western Cape.

OBJECTIVES: To record the number of haemophilicas aged 0-18 years in the Western Cape (WC), what event led to the diagnosis, the level of clotting factor, treatment, functional status of their joints and impact of the disease on the family. DESIGN: A prospective study of patients registered with the South African National Haemophilia Registry and new patients, utilising the patients' paediatricians, hospital records, patient and guardian interviews, physical examination and provincial nurse haemophilia co-ordinators. SETTING: Haemophilia care centres at the three WC academic hospitals, regional hospitals and homes of patients. Two elective medical students, MHH and JJH, collected the information. SUBJECTS: All boys with confirmed haemophilia A or B in the WC. OUTCOME MEASURES: Events that led to diagnosis, degree of haemophilia, use of clotting factor, functional status, and effect on family. RESULTS: Of 78 patients (59 haemophilia A, 19 haemophilia B) identified, 49 could be studied. Forty-three per cent had severe, 29% moderate and 22% mild disease (6% unknown). Family history was present in 49%, but led to diagnosis in only 12%. The most common first symptoms were subcutaneous and mucosal bleeding. Delay in diagnosis varied from 0 to 9 months. Twenty-nine per cent of guardians were suspected of child abuse. RSA produced clotting factor was used 'on demand' in 73% of patients, for periodic prophylaxis in 20% and as continuous prophylaxis in 7%. Joints were functionally restricted in 43% of patients. The majority of guardians (59%) said the disease had a major impact on the family. CONCLUSIONS: The diagnosis of haemophilia in children with a positive family history was often delayed. Haemophilia causes significant morbidity in our patients and their families.

Adolescent↗
PubMed2002

Conceptional considerations for a German influenza pandemic preparedness plan.

A pandemic appearance of influenza A virus must be expected at any time. The limitations of health preserving and life-saving resources, which will inevitably be reached in the event of a pandemic, will be accompanied by ethical and possibly social conflicts, which can be lessened or resolved only through precautionary planning, clearly specified competencies and transparent decisions within a social consensus. In case of a shortage of vaccines and virostatic agents, decisions will have to be made with regard to the segment of the population that absolutely must be vaccinated. It is currently estimated that a (monovalent) vaccine developed for a new pandemic strain would only suffice for the single vaccination of approximately half of the German population after a year; only 10-14 million vaccine dosages would be available to provide basic immunization and single boosters to personnel required to maintain basic medical care and essential infrastructure after half a year. In the event of local influenza outbreaks, antiviral chemotherapeutic agents could be used to close the gap until a vaccine can become effective. Even if suitable influenza vaccines and virostatic agents are not sufficiently available at the start of a pandemic, it is still possible to at least prevent an outbreak of two of the most feared secondary infections that accompany influenza: pneumococcal pneumonia or meningitis and illnesses resulting from Haemophilus influenzae. Agreement still needs to be reached with manufacturers for guaranteeing the necessary vaccine production or ensuring that they have a sufficient stock to meet the minimum demand for antiviral agents and agents for symptomatic treatment.

Antiviral Agents↗
PubMed2002

p38-avidity-ELISA: examination of herds experiencing epidemic or endemic Neospora caninum-associated bovine abortion.

An enzyme-linked immunosorbent assay (ELISA) was established to measure the avidity of bovine IgG directed against p38, a surface antigen (NCSRS2) of Neospora caninum tachyzoites. In the sera of dams intravenously infected with N. caninum NC-1, the p38-specific avidity increased from initially below 40% up to avidity indices between 50 and 80% after days 23 and 91 p.i. The p38-avidity-ELISA was used to examine various herds that had experienced endemic and epidemic N. caninum-associated bovine abortions. In herds with endemic abortion, generally high avidity indices of N. caninum-specific IgG were detected. This finding and the observation of an association between the seropositivity of dams and that of their offspring suggested a predominantly vertical transmission of the parasite among the animals of these herds, thus indicating chronic infection of these cattle. In contrast, for herds experiencing epidemic abortion: (i) an association regarding seropositivity of dams and their daughters could not be shown and (ii) a generally low avidity of p38-specific IgG in the sera from aborting dams was determined. This indicates recent postnatal transmission of N. caninum in these herds. A linear regression model explaining the avidity of p38-specific IgG was significantly influenced by the time span between sampling and the occurrence of the first abortion of the epidemic in herds with an N. caninum-associated abortion storm. Another factor significantly contributing to the model was the proportion of dams at risk that had aborted in the herds (i.e. the severity of the abortion epidemic). A possible explanation for this observation is that herds experiencing heavy abortion are sampled earlier after the onset of the epidemic than others that have a less severe abortion storm.

Abortion, Veterinary↗
PubMed2002

Laparoscopic transgastric endoscopic retrograde cholangiopancreatography for benign common bile duct stricture after Roux-en-Y gastric bypass.

Access to the gastric remnant and duodenum is lost after laparoscopic Roux-en-Y gastric bypass for morbid obesity. Traditionally, a percutaneous transhepatic access to the common bile duct has been used to manage choledocholithiasis and duct strictures. We present a novel method of laparoscopic transgastric endoscopic retrograde cholangiopancreatography for managing a benign biliary stricture after a Roux-en-Y gastric bypass.

Anastomosis, Roux-en-Y↗
PubMed2002

Neospora caninum and Waddlia chondrophila strain 2032/99 in a septic stillborn calf.

Characteristics of an intracellularly growing micro-organism isolated from an aborted bovine foetus are described. The organism replicated within cytoplasmic vacuoles, was resistant to penicillin and exhibited structural characteristics compatible with Waddlia chondrophila. An ELISA specific for Chlamydia spp., immunofluorescence tests using antibodies directed against Chlamydia spp. or Simkania negevensis, and PCR using Chlamydia-specific primers showed that the agent was distinct from Chlamydiae or S. negevensis. Determination of 16S and partial 23S ribosomal RNA gene sequences in combination with the PCR results and the morphological, antigenic and developmental characteristics provided evidence that the isolate 2032/99 can be classified as W. chondrophila or a closely related organism.

Abortion, Veterinary↗
PubMed2002

[The Frankfurt concept for health counseling for men].

The discussion on the difference between the sexes received significant impulses from the formation of feminist theory. Masculinity was interpreted in a rather morally negative manner. Masculinity continuously endeavors to achieve reproduction and self-confirmation. Competitive pursuit of hegemony is the preeminent pattern by which masculine identity is formed. Male socialization leads to externalization, which impedes the development of communicative skills. Males tend to lead a high-risk life-style, which instrumentalizes their body. Symptoms are less often interpreted as warning signals, reflected in a significantly reduced life expectancy in comparison to females. In view of the specific male socialization, the Frankfurt concept of "men's health counseling" attempts to create a professional atmosphere in which men seeking advice are offered the opportunity to consult a specialist on all topics of men's health anonymously and, for the moment, free of charge.

Gender Identity↗
PubMed2002

Division of the corpus callosum into subregions.

Various attempts have been made to subdivide the corpus callosum (CC) into anatomically and functionally distinct subareas. A promising current approach is the use of factor analytic techniques in conjunction with traced MRI images. The traced images are divided into 99 percentile slices, where the widths of the percentile slices are used as variables that are entered into the analysis (Denenberg, Kertesz & Cowell, 1991). Studies that use this technique agree broadly between 6 and 7 factors, but available factor solutions contain inconsistencies and large gaps, which arise when many of the percentile slices do not load appreciably on any of the factors. The present study uses a larger number of brains (N = 184), all normalized, and some methodological refinements in the analysis of the traced MRI images of the CC. A stable 7 factor solution was found, and the factor structure for males and females was very similar.

Adult↗
PubMed2002

The EORTC clinical research coordinators group. European Organisation for Research and Treatment of Cancer.

The Clinical Research Coordinators Group (CRCG) is an umbrella organisation, compiled from four existing groups, namely the Oncology Nurses Group, the Data Management Group, the Radiation Technologists Group and the Early Clinical Studies Group Research Nurses. From the existing steering committees, a new board was formed and consists of two members per group. The CRCG will function as an independent group within the EORTC. The CRCG will create conditions and standards for implementing and conducting clinical protocols according to Good Clinical Practice.

Europe↗
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↗