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1.
Eur J Neurol ; 23(1): 148-53, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26268364

ABSTRACT

BACKGROUND AND PURPOSE: Whereas traditional views of language processing in the brain have assumed that the language function is concentrated to a limited number of cortical areas (Broca's and Wernicke's areas), current knowledge points at a much more complex system of language and speech processing involving many brain areas, both cortical and subcortical. The purpose of the current study was to make an unbiased assessment of which cerebral areas are affected in first-ever acute ischaemic stroke patients identified as having language and speech impairments according to the National Institutes of Health Stroke Scale (NIHSS). METHODS: Data from 34 patients with language and speech impairment, with a score of 1-3 on item 9 of the NIHSS, following ischaemic stroke were collected from the Lund Stroke Register. Magnetic resonance images acquired up to 20 days after stroke onset were used to create an overlap lesion image using MRIcron software. RESULTS: The classical language areas, Wernicke's and Broca's areas, were affected in less than one-fourth of the patients. The most frequently affected region was a subcortical region--the left caudate nucleus and the adjacent corona radiata. CONCLUSIONS: These findings contribute to the growing body of evidence that the basal ganglia have a crucial role in the control over language and speech processing.


Subject(s)
Brain Ischemia , Caudate Nucleus/pathology , Language Disorders , Stroke , Adult , Aged , Brain Ischemia/complications , Brain Ischemia/pathology , Brain Ischemia/physiopathology , Female , Humans , Language Disorders/etiology , Language Disorders/pathology , Language Disorders/physiopathology , Male , Middle Aged , Speech Disorders/etiology , Speech Disorders/pathology , Speech Disorders/physiopathology , Stroke/complications , Stroke/pathology , Stroke/physiopathology , Young Adult
2.
Neurocase ; 20(2): 192-207, 2014 Apr.
Article in English | MEDLINE | ID: mdl-23425233

ABSTRACT

The present study investigated hierarchical lexical semantic structure in oral descriptions of concrete word meanings produced by a subject (ZZ) diagnosed with anomic aphasia due to left occipital lesions. The focus of the analysis was production of a) nouns at different levels of semantic specificity (e.g., "robin"-"bird"-"animal") and b) words describing sensory or motor experiences (e.g., "blue," "soft," "fly"). Results show that in contrast to healthy and aphasic controls, who produced words at all levels of specificity and mainly vision-related sensory information, ZZ produced almost exclusively nouns at the most non-specific levels and words associated with sound and movement.


Subject(s)
Anomia/diagnosis , Occipital Lobe/pathology , Semantics , Aged , Anomia/etiology , Humans , Male , Stroke/complications
3.
J Am Chem Soc ; 132(29): 10171-83, 2010 Jul 28.
Article in English | MEDLINE | ID: mdl-20586474

ABSTRACT

We describe the synthesis and characterization of the homologous p-iodophenylsilsesquioxanes (SQs) [p-I-C(6)H(4)SiO(1.5)](n) (n = 8, 10, 12) via ICl-promoted iodination (-40 to -60 degrees C) with overall yields of 80-90% and > 95% para selectivity following recrystallization. Characterization by NMR, FTIR, TGA, and single-crystal X-ray diffraction are reported and compared to data previously published for I(8)OPS. Coincidentally, we report a new synthesis of the elusive pentagonal decaphenyl SQ (dPS) [C(6)H(4)SiO(1.5)](10) and its characterization by NMR and single-crystal X-ray studies. These unique macromolecules possess equivalent chemical functionality but varying symmetries (cubic, pentagonal, and D(2d) dodecahedral), offering the potential to develop homologous series of functionalized star and dendrimer compounds with quite different core geometries and thereby providing the potential to greatly vary structure-property relationships in derivative compounds and nanocomposites made therefrom. We find that all three compounds decompose on heating to approximately 400 degrees C/N(2) with loss of I(2) to form robust, microporous materials with BET surface areas of 500-700 m(2)/g, pore volumes of 0.25-0.31 cm(3)/g, average pore widths of 8 A, and oxidative stabilities > or = 500 degrees C and with solid-phase morphologies varying from crystalline to mostly amorphous, as indicated by powder XRD and SEM studies. These latter findings point to important symmetry effects relating directly to packing in the crystalline phase prior to thermolysis.

4.
J Am Chem Soc ; 132(11): 3708-22, 2010 Mar 24.
Article in English | MEDLINE | ID: mdl-20187633

ABSTRACT

A set of stilbene-substituted octasilicates [p-RStil(x)Ph(8-x)SiO(1.5)](8) (R = H, Me, MeO, Cl, NMe(2) and x = 5.3-8) and [o-MeStilSiO(1.5)](8) were prepared. Model compounds were also prepared including the corner and half cages: [p-MeStilSi(OEt)(3)], [p-Me(2)NStilSi(OSiMe(3))(3)], and [p-Me(2)NStilSi(O)(OSiMe)](4). These compounds were characterized by MALDI-TOF, TGA, FTIR, and (1)H NMR techniques. Their photophysical properties were characterized by UV-vis, two-photon absorption, and cathodoluminescence spectroscopy (on solid powders), including studies on the effects of solvent polarity and changes in concentration. These molecules are typically soluble, easily purified, and robust, showing T(d(5%)) > 400 degrees C in air. The full and partial cages all show UV-vis absorption spectra (in THF) identical to the spectrum of trans-stilbene, except for [o-MeStilSiO(1.5)](8), which exhibits an absorption spectrum blue-shifted from trans-stilbene. However, the partial cages show emissions that are red-shifted by approximately 20 nm, as found for stilbene-siloxane macrocycles, suggesting some interaction of the silicon center(s) with the stilbene pi* orbital in both the corner and half cages. In contrast, the emission spectra of the full cages show red-shifts of 60-100 nm. These large red-shifts are supported by density functional theoretical calculations and proposed to result from interactions of the stilbene pi* orbitals with a LUMO centered within the cage that has 4A(1) symmetry and involves contributions from all Si and oxygen atoms and the organic substituents. Given that this LUMO has 3-D symmetry, it appears that all of the stilbene units interact in the excited state, consistent with theoretical results, which show an increased red-shift with an increase in the functionalization of a single corner to functionalization of all eight corners with stilbene. In the case of the Me(2)N- derivatives, this interaction is primarily a charge-transfer interaction, as witnessed by the influence of solvent polarity on the emission behavior. More importantly, the two-photon absorption behavior is 2-3 times greater on a per p-Me(2)Nstilbene basis for the full cage than for the corner or half cages. Similar observations were made for p-NH(2)stilbenevinyl(8)OS cages, where the greater conjugation lengths led to even greater red-shifts (120 nm) and two-photon absorption cross sections. Cathodoluminescence studies done on [p-MeStilSiO(1.5)](8) or [p-MeStilOS](8) powders exhibit essentially the same emissions as seen in solution at high dilution. Given that only the emissions are greatly red-shifted in these molecules, whereas the ground-state UV-vis absorptions are not changed from trans-stilbene, except for the ortho derivative, which is blue-shifted 10 nm. It appears that the interactions are only in the excited state. Theoretical results show that the HOMO and LUMO states are always the pi and pi* states on the stilbene, which show very weak shifts with increasing degrees of functionalization, consistent with the small changes in the UV-vis spectra. The band gap between the lowest unoccupied 4a1 symmetry core state localized inside the silsesquioxane cage and the highest occupied state (pi state on stilbene), however, is markedly decreased as the number of stilbene functional groups is increased. This is consistent with the significant red-shifts in the emission spectra. The results suggest that the emission occurs from the 4a1 state localized on the cage. Moreover, for the compounds [p-RStil(6-7)Ph(2-1)OS](8), the emissions are blue-shifted compared to those of the fully substituted compounds, suggesting the molecular symmetry is reduced (from cubic), thereby reducing the potential for 3-D delocalization and raising the energy of the LUMO. The implications are that these octafunctional molecules exhibit some form of 3-D interaction in the excited state that might permit their use as molecular transistors as well as for energy collection and dispersion as molecular antennas, for example, and for nonlinear optical applications.

5.
AJNR Am J Neuroradiol ; 31(6): 1003-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20110373

ABSTRACT

BACKGROUND AND PURPOSE: Recently introduced 320-detector row CT enables whole brain perfusion imaging compared to a limited scanning area in 64-detector row CT. Our aim was to evaluate patient radiation exposure in comprehensive stroke imaging by using multidetector row CT consisting of standard CT of the head, CTA of cerebral and cervical vessels, and CTP. MATERIAL AND METHODS: Organ doses were measured by using LiF-TLDs located at several organ sites in an Alderson-Rando phantom. Effective doses were derived from these measurements. Stroke protocols including noncontrast head CT, CTA of cerebral and cervical vessels, and CTP were performed on 320- and 64-detector row scanners. RESULTS: Measured effective doses for the different scanning protocols ranged between 1.61 and 4.56 mSv, resulting in an effective dose for complete stroke imaging of 7.52/7.54 mSv (m/f) for 64-detector row CT and 10.56/10.6 mSv (m/f) for 320-detector row CT. The highest organ doses within the area of the primary beam were measured in the skin (92 mGy) and cerebral hemispheres (69.91 mGy). Use of an eye-protection device resulted in a 54% decrease of the lens dose measured for the combo protocol for whole-brain perfusion with the 320-detector row CT scanner. CONCLUSIONS: Phantom measurements indicate that comprehensive stroke imaging with multidetector row CT may result in effective radiation doses from 7.52 mSv (64-detector row CT) to 10.6 mSv (320-detector row CT). The technique of 320-detector row CT offers additional information on the time course of vascular enhancement and whole-brain perfusion. Physicians should weigh the potential of the new technique against the higher radiation dose that is needed. Critical doses that would cause organ damage were not reached.


Subject(s)
Brain/diagnostic imaging , Phantoms, Imaging , Radiometry/methods , Stroke/diagnostic imaging , Tomography, X-Ray Computed/instrumentation , Tomography, X-Ray Computed/methods , Equipment Safety , Female , Humans , Lens, Crystalline/diagnostic imaging , Male , Models, Anatomic , Radiation Dosage , Reproducibility of Results , Skull Base/diagnostic imaging , Tomography, X-Ray Computed/standards
6.
Eur J Pediatr Surg ; 16(5): 329-33, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17160777

ABSTRACT

The study objective is to evaluate the results of our surgical technique for children with congenital adrenal hyperplasia and ambiguous genitalia at the University Hospital of Heidelberg, Department of Paediatric Surgery. The records of 19 patients with congenital adrenal hyperplasia treated between 1972 and 2004 were reviewed with respect to age at surgery, operative procedures and outcome. We describe the recession clitoroplasty technique currently used in our hospital and highlight the importance of short and long-term follow-up results with respect to appearance, position and size of the clitoris and quality of the vagina. One-stage recession clitoroplasty and vaginoplasty gives very satisfactory cosmetic and functional results, with few complications and a reduced need for secondary surgical interventions. The results of this study support the assumption that total correction can be achieved through a single-stage operation, performed in infancy.


Subject(s)
Adrenal Hyperplasia, Congenital/surgery , Clitoris/surgery , Gynecologic Surgical Procedures/methods , Vagina/surgery , Child, Preschool , Female , Gynecologic Surgical Procedures/adverse effects , Humans , Reoperation , Retrospective Studies
7.
Int J Radiat Oncol Biol Phys ; 49(5): 1451-60, 2001 Apr 01.
Article in English | MEDLINE | ID: mdl-11286853

ABSTRACT

PURPOSE: Conformal stereotactic radiosurgery and radiotherapy using a linear accelerator and a micromultileaf collimator (mMLC) offer the possibility of irradiating irregularly shaped target volumes. Dynamic arc radiosurgery and radiotherapy, i.e., stereotactic radiation therapy combining a moving gantry with a dynamic mMLC, enable the radiation even of lesions with concave structures. METHODS AND MATERIALS: The dynamic arc method requires additional tools for quality assurance (QA) and three-dimensional verification at a high spatial resolution. A QA program was developed. Dose distributions of planning target volumes with concavities were investigated in polymer gel phantoms. The radiation-induced change of the relaxation rate R(2) was measured by magnetic resonance imaging. The distributions were compared with image processing tools. RESULTS: Using the therapy-planning software BrainSCAN 4.0 (and 4.1 beta) in combination with the mMLC m3, deviations between the planned and measured 90% isodoses of about 2 mm were registered in the isocenter plane. Three-dimensional verification was feasible in the range of accuracy achieved in planning and dose measurement. CONCLUSIONS: Dynamic arc radiosurgery and radiotherapy offer excellent conformation even for complicated planning target volumes with concavities. The dose distribution calculated with the treatment-planning software used can be accomplished with the available equipment. Patients can be treated by dynamic arc radiosurgery and radiotherapy.


Subject(s)
Phantoms, Imaging , Radiosurgery/methods , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Conformal/methods , Calibration , Combined Modality Therapy , Humans , Magnetic Resonance Imaging , Particle Accelerators , Physical Phenomena , Physics , Quality Control , Radiosurgery/instrumentation , Radiosurgery/standards , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/instrumentation , Radiotherapy Planning, Computer-Assisted/standards , Radiotherapy, Conformal/instrumentation , Radiotherapy, Conformal/standards
10.
J Infect Dis ; 172(1): 296-301, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7797935

ABSTRACT

Thirteen patients (median age, 20 years) with life-threatening primary septic shock (10 meningococcal, 3 pneumococcal infections) were studied prospectively. All had a short history of sepsis (< or = 24 h) and no severe underlying disease. Two (15%) died. The logarithm of the initial plasma levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-6, IL-1 receptor antagonist (ra), and plasminogen activator inhibitor (PAI)-1 correlated significantly with APACHE II scores (r2 = .67, .57, .68, .81, and .68, respectively). The plasma levels of endotoxin, TNF-alpha, IL-1 beta, and PAI-1 decreased toward normal levels within the first 24 h of treatment, but IL-6 and IL-1ra levels remained high until clinical recovery. On admission, the molar excess of IL-1ra to IL-1 beta was > 2000-fold in 11 of the 13 patients. Acute plasmapheresis in 11 of the 13 patients significantly increased the plasma clearance of TNF-alpha (P = .02).


Subject(s)
Cytokines/blood , Shock, Septic/immunology , Shock, Septic/physiopathology , Adolescent , Adult , Biomarkers/blood , Female , Humans , Insulin Receptor Substrate Proteins , Interleukin-1/blood , Interleukin-6/blood , Male , Meningococcal Infections/blood , Meningococcal Infections/immunology , Meningococcal Infections/physiopathology , Middle Aged , Phosphoproteins/blood , Plasminogen Activator Inhibitor 1/blood , Pneumococcal Infections/blood , Pneumococcal Infections/immunology , Pneumococcal Infections/physiopathology , Predictive Value of Tests , Prognosis , Prospective Studies , Shock, Septic/blood , Time Factors , Tumor Necrosis Factor-alpha/analysis
11.
J Hosp Infect ; 30(1): 57-63, 1995 May.
Article in English | MEDLINE | ID: mdl-7665883

ABSTRACT

An outbreak of hepatitis B virus (HBV) infection in a haemodialysis unit is described. Four patients in the unit contracted subclinical HBV infection within three months. DNA sequence analysis of the S gene of HBV isolates from chronic carriers and newly infected patients in the unit aided in tracing possible transmission pathways. Three newly infected patients had received partial or complete HBV vaccination previously. HBV was rapidly cleared from all three although the anti-HBs titre had not reached 10 IU L-1 in any of them at the time of infection.


Subject(s)
Cross Infection/epidemiology , Disease Outbreaks , Hepatitis B virus/genetics , Hepatitis B/epidemiology , Sequence Analysis, DNA , Cross Infection/prevention & control , Cross Infection/virology , DNA, Viral , Hemodialysis Units, Hospital , Hepatitis B/prevention & control , Hepatitis B/virology , Hepatitis B Vaccines , Hepatitis B virus/isolation & purification , Humans , Sweden/epidemiology , Vaccination
12.
Nephron ; 65(1): 40-5, 1993.
Article in English | MEDLINE | ID: mdl-7692314

ABSTRACT

The prevalence and incidence of hepatitis C virus (HCV) infections were studied in 236 dialysis patients and related to clinical data at two hospitals in Stockholm, Sweden. Patients were followed during 12 months and tested by 1st- and 2nd-generation anti-HCV assays. Time of seroconversion to HCV could be determined by retrospective analysis of stored serum samples. A total of 36 (15%) patients were anti-HCV positive. Time of seroconversion could be determined for 23 patients and was in the majority of cases associated with blood transfusions, but late seroconversion (more than 6 months after transfusion) as well as lack of transfusion in some cases implied that HCV might be transmitted through dialysis equipment. Persistence of elevated alanine amino-transferase levels for more than 6 months occurred in 17% of anti-HCV-positive patients. In conclusion, routes of transmission in dialysis units have to be further evaluated since routes other than transfusion may occur and diagnosis may be delayed in this group of patients probably due to a poor immunological response.


Subject(s)
Hepatitis Antibodies/blood , Hepatitis C/transmission , Renal Dialysis/adverse effects , Alanine Transaminase/blood , Hepacivirus/immunology , Hepatitis C/epidemiology , Hepatitis C/immunology , Hepatitis C Antibodies , Humans , Peritoneal Dialysis, Continuous Ambulatory/adverse effects , Prospective Studies , Retrospective Studies , Sweden/epidemiology , Time Factors , Transfusion Reaction
13.
Scand J Infect Dis ; 25(6): 757-61, 1993.
Article in English | MEDLINE | ID: mdl-8052817

ABSTRACT

14 patients (mean age 25.5 yrs) with life-threatening primary septic shock were eligible for treatment with acute plasmapheresis in a prospective study. They had a short history of sepsis and had no severe underlying disease. 10/14 patients had systemic meningococcal disease. All patients were severely ill with a mean APACHE II score of 25.0. 12/14 patients were treated with plasmapheresis exchanging 1 plasma volume within hours of admission. 11/14 patients survived without major sequelae and 3 (21%) died of irreversible septic shock. This mortality is lower than that predicted from the APACHE II scores (55.2%). A subgroup of plasmapheresis-treated patients with septic shock and extensive petechiae were compared to a historical control group. The mortality in the treatment group was 1/7 (14%) versus 8/21 (38%) in the control group. We conclude that acute plasmapheresis may be a therapeutic option in the early stages of severe primary non-surgical septic shock.


Subject(s)
Plasmapheresis/methods , Shock, Septic/therapy , Adolescent , Adult , Aged , Child , Critical Care , Data Interpretation, Statistical , Female , Humans , Male , Middle Aged , Prospective Studies , Shock, Septic/mortality
15.
Scand J Urol Nephrol ; 26(2): 201-3, 1992.
Article in English | MEDLINE | ID: mdl-1626212

ABSTRACT

A 49-year-old woman had polycystic kidneys and liver cysts first diagnosed in 1968. She presented with hepatic and renal failure in 1980 and by 1988 was undergoing regular haemodialysis. In February 1989 she had bilateral nephrectomy (before renal transplantation) but developed septic shock and died. The reported mortality of bilateral nephrectomy before kidney transplantation is about 5%, and patients should be carefully selected and assessed before operation.


Subject(s)
Kidney Transplantation/pathology , Nephrectomy , Polycystic Kidney Diseases/surgery , Postoperative Complications/pathology , Abscess/pathology , Female , Humans , Kidney/pathology , Liver Diseases/pathology , Middle Aged , Peritonitis/pathology , Polycystic Kidney Diseases/pathology , Sepsis/pathology
16.
J Intern Med ; 231(1): 59-65, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1732400

ABSTRACT

A five-year follow-up, by means of a personal interview, was performed on patients below the age of 40 years with acute chest pain without obvious organic cause (n = 64). They had been consecutively admitted to the emergency unit over a period of 8 weeks, and had all been subjected to a thorough medical and psychosocial investigation with feedback soon after the initial consultation (investigation patient group, IP). For comparison, a non-investigation patient (NIP) group (n = 51) was recruited over a period of 8 separate weeks. Half of the patients in each group reported at the follow-up that they continued to suffer from chest pain. Compared to normal subjects, they reported more depression. This means that the initial research programme performed in the investigation group had no sustained therapeutic effect compared to routine care at the emergency unit. Tension, anxiety and number of consultations with a physician, as reported in the initial investigation, were negatively correlated with the outcome at follow-up. We conclude that acute chest pain without obvious organic cause in young adults is a condition with an excellent prognosis in strictly physical terms. However, a high proportion of the patients continue to suffer from chest pain for several years, and many of them continue to be consumers of medical resources. We therefore suggest that therapeutic programmes should be developed, particularly for those who report psychological symptoms and those with a history of many consultations with physicians.


Subject(s)
Chest Pain/psychology , Acute Disease , Adult , Aged , Anxiety/complications , Chest Pain/etiology , Depression/complications , Emergencies , Female , Follow-Up Studies , Humans , Interviews as Topic , Male , Middle Aged , Morbidity
17.
Rev Environ Health ; 9(4): 191-205, 1991.
Article in English | MEDLINE | ID: mdl-1842454

ABSTRACT

Elevated levels of aluminum in brain tissue have been found in demented patients with Alzheimer's disease, with ALS-PD complex of Guam and with dialysis encephalopathy. A possible etiological relationship between enhanced aluminum exposure and impaired mental function was suggested both for ALS-PD of Guam (a region where high contents of aluminum in water are found) and for dialysis encephalopathy which appears in dialyzed patients exposed to high doses of aluminum in medications and in dialysate fluid. The role of aluminum in Alzheimer's disease is not known as is the question of life-long aluminum accumulation in healthy human beings. In this review we have limited ourselves to the issue of oral aluminum ingestion and the possible neurotoxic consequences of such exposure. The following topics are summarized: 1. Physiological mechanisms involved in ingestion and intestinal absorption of aluminum and the influences of pH and available organic complexing agents on these processes. 2. Effects of an aluminum-enriched diet on behavior and on brain metabolism. 3. Dietary sources of aluminum and elevated loads of this substance due to prolonged intake of aluminum-containing medications. The main conclusion of this summary is that aluminum is absorbed and may accumulate in different organs in both adults and infants. Two groups seem to be at particular risk for aluminum related toxicity: people with chronic renal failure treated with aluminum-containing medications and pre-term infants fed on aluminum containing formulate. It seems probable that at least upon short term exposure the healthy human body can defend itself adequately from aluminum's toxic effects. However, not enough information is available on possible effects of life-long exposure to aluminum in the environment, diet and medications, which over decades may lead to accumulation of this substance with expressions of toxicity. Therefore, the question of aluminum's relevance to dementive diseases cannot yet be adequately answered.


Subject(s)
Aluminum/adverse effects , Aluminum/pharmacokinetics , Alzheimer Disease/chemically induced , Intestinal Absorption , Aluminum/analysis , Aluminum/chemistry , Animals , Brain/drug effects , Brain/metabolism , Cats , Cooking and Eating Utensils , Diet/adverse effects , Humans , Infant , Infant Food/analysis , Mice , Pharmaceutical Preparations/chemistry , Rats , Tea/chemistry
18.
J Intern Med ; 230(3): 271-7, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1895050

ABSTRACT

Clinical symptoms were studied in 69 consecutive patients below the age of 40 years who were attending the emergency unit because of unexplained chest pain. In a structured interview a few weeks after the emergency visit, only one-third of the patients reported that they believed in the doctor's diagnosis; they believed in a psychological or cardiac origin of the pain more often than the doctors. The chest pain was most often described as oppressive and/or stabbing. In 95% of cases it was central or left-sided. Associated symptoms were commonly reported, breathlessness being most commonly reported by two-thirds of the patients, followed by dizziness, palpitation and numbness/tingling. Mental symptoms such as tiredness, anxiety and tension were frequently reported. On the basis of the background literature the aetiology is discussed. We conclude that immediate symptom analysis, including psychosomatic symptoms, particularly breathing problems, is of central importance.


Subject(s)
Chest Pain/etiology , Emergency Service, Hospital , Adult , Chest Pain/complications , Consumer Behavior , Diagnosis, Differential , Dizziness/complications , Female , Heart Rate , Humans , Male , Paresthesia/complications , Recurrence , Referral and Consultation , Respiration Disorders/complications , Sweden
19.
J Intern Med ; 228(3): 223-7, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2401872

ABSTRACT

A hyperventilation provocation test (HVPT) was performed on a group (n = 63) of consecutive patients, below the age of 40 years, attending an emergency care unit complaining of chest pain without obvious organic cause. The results were compared with those for a control group (n = 32). There was no tendency to hyperventilate in the patient group, either after discontinuing hyperventilation or during the ensuing relaxation period. PETCO2 measurements during this time thus showed no significant differences between the patient group and the control group. During the HVPT, 44% of patients reported three or more listed symptoms familiar to them from earlier occasions and regarded as typical of hyperventilation, compared to 23% of the controls (P less than 0.05). In a previously reported study, 38% of the patients were found to have similar symptoms during standardized mental stress, despite lack of hypocapnia. It is concluded that, on the basis of PETCO2 measurements, there were no signs of abnormal hyperventilation in the patient group. Moreover, the HVPT did not appear to be specific for diagnosis of hyperventilation syndrome, since mental stress itself was able to reproduce symptoms without concomitant hypocapnia, and since the provocation test was 'positive' in many control subjects.


Subject(s)
Chest Pain/etiology , Hyperventilation/physiopathology , Stress, Psychological/physiopathology , Adult , Blood Pressure/physiology , Female , Heart Rate/physiology , Humans , Male
20.
Mutagenesis ; 5(1): 25-30, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2184306

ABSTRACT

Ten derivatives of N-benzylphenanthrene 9,10-imine with different substituents on the phenyl ring were synthesized and subjected to mutagenicity tests in Salmonella typhimurium TA100. While electron donating groups were found to enhance the biological activity, electron attracting and bulky substituents lowered the mutagenic potency. A similar dependence on the electronic structure was observed in triethylamine/acetonitrile-promoted interaction of the title imines and 4-nitrothiophenol. This similarity suggests that both biochemical and chemical processes involve mechanisms in which protonation of the aziridine nitrogen is rate controlling, and the attack of the cellular or model nucleophile is a fast step. In contrast to these processes, the reaction of the imines with 4-nitrothiophenol in the presence of 1,5-diazabicyclo[4.3.0] non-5-ene proved to proceed by an SN2 mechanism and to be enhanced by electron attracting substituents.


Subject(s)
Imines/pharmacology , Mutation , Phenanthrenes/pharmacology , Chemical Phenomena , Chemistry , Electrons , Kinetics , Magnetic Resonance Spectroscopy , Molecular Structure , Mutagenicity Tests , Salmonella typhimurium/drug effects , Structure-Activity Relationship
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