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At least 1,279 records · Page 71Linked to original sources
PubMed1995

Relationships between food, wine, and beer-precipitated migrainous headaches.

Five hundred seventy-seven consecutive patients attending the Princess Margaret Migraine Clinic from 1989 to 1991 have been questioned about dietary precipitants of their headaches. Four hundred twenty-nine patients had migraine, of which 16.5% reported that headaches could be precipitated by cheese or chocolate, and nearly always both. Of the migraine patients, 18.4% reported sensitivity to all alcoholic drinks, while another 11.8% were sensitive to red wine but not to white wine; 28% of the migrainous patients reported that beer would precipitate headaches. There was a definite statistical association between sensitivity to cheese/chocolate and to red wine (P < 0.001) and also to beer (P < 0.001), but none between diet sensitivity and sensitivity to alcoholic drinks in general. None of 40 patients with tension headache (diagnosed by International Headache Society criteria) reported sensitivity to foods, and only one was sensitive to alcoholic drinks. The prevalence of sensitivity among 46 patients with some migrainous features was intermediate between the migraine and tension headache categories. It is concluded that cheese/chocolate and red wine sensitivity, in particular, have closely related mechanisms, in some way related more to migraine than to more chronic tension-type headache, while quite separate mechanisms play a major role in sensitivity to alcoholic drinks in general.

Beer↗
PubMed2005

Water deprivation: a new migraine precipitant.

Fifty migraineurs were asked if insufficient fluid intake could provoke their migraine attacks. Twenty replied "yes," 7 were doubtfully positive, and 23 said "no." In addition 14 of 45 migraineurs at a meeting of the British Migraine association (UK) also recognized fluid deprivation as one of their migraine triggers. Thus a total of 34 of 95 migraineurs knew that dehydration could provoke their attacks, a precipitant not recognized by the medical profession. This indicates that we can add fluid deprivation to our list of migraine precipitants. It would be interesting to know the extent to which it applies in other climates. Further research is needed into the mechanism of this precipitant.

Adolescent↗
PubMed2003

Modulation of oral morphine antinociceptive tolerance and naloxone-precipitated withdrawal signs by oral Delta 9-tetrahydrocannabinol.

Previous studies have demonstrated a functional interaction between cannabinoid and opioid systems in the development and expression of morphine tolerance and dependence. In these experiments, we examined the effect of a low oral dose of Delta 9-tetrahydrocannabinol (Delta 9-THC) on the development of oral morphine tolerance and the expression of naloxone-precipitated morphine withdrawal signs of jumping and diarrhea in ICR mice. Chronic treatment with high-dose oral morphine produced a 3.12-fold antinociceptive tolerance. Tolerance to morphine was prevented in groups receiving a daily cotreatment with a nonanalgetic dose (20 mg/kg p.o.) of Delta 9-THC, except when challenged with a very high dose of morphine. The chronic coadministration of low-dose Delta 9-THC also reduced naloxone-precipitated (1 mg/kg s.c.) platform jumping by 50% but did not reduce diarrhea. In separate experiments, mice treated chronically with high-dose morphine p.o. were not cross-tolerant to Delta 9-THC; in fact, these morphine-tolerant mice were more sensitive to the acute antinociceptive effects of Delta 9-THC. Delta 9-THC (20 mg/kg p.o.) also reduced naloxone-precipitated jumping but not diarrhea when administered acutely to morphine-tolerant mice. These results represent the first evidence that oral morphine tolerance and dependence can be circumvented by coadministration of a nonanalgetic dose of Delta 9-THC p.o. In summary, cotreatment with a combination of morphine and Delta 9-THC may prove clinically beneficial in that long-term morphine efficacy is maintained.

Administration, Oral↗
PubMed1962

Carbonic anhydrase and the precipitation of apatite.

On theoretical grounds it is unlikely that the catalytic action of the enzyme carbonic anhydrase would be required for the precipitation of apatite in vitro. The presence of carbonic anhydrase in either active or inactivate form did not initiate precipitation in a metastable calcifying solution. It is unlikely that carbonate (or bicarbonate) ions are essential for the precipitation of apatite in vitro or in vivo.

Apatites↗
PubMed1962

Synthetic acrylic gel: a new medium for the study of immune precipitates.

The physicochemical properties of photocatalyzed Cyanogum gel offer practical advantages in the analysis of specific immunological precipitation techniques: use of any buffer at any pH; most probable neutrality for stains or reagents; remarkable resolution of the immunological precipitates, visible microscopically; possibility of direct dark-background examination of the precipitates, so that their kinetics can be studied and they can be photographed before dyeing and staining. This gel seems particularly suitable for immunoanalysis of complex and unstable antigenic products, such as tissue homogenates.

Antigens↗
PubMed2001

Quantification of soil-to-plant transport of recombinant nucleopolyhedrovirus: effects of soil type and moisture, air currents, and precipitation.

Significantly more occlusion bodies (OB) of DuPont viral construct HzSNPV-LqhIT2, expressing a scorpion toxin, were transported by artificial rainfall to cotton plants from sandy soil (70:15:15 sand-silt-clay) than from silt (15:70:15) and significantly more from silt than from clay (15:15:70). The amounts transported by 5 versus 50 mm of precipitation were the same, and transport was zero when there was no precipitation. In treatments that included precipitation, the mean number of viable OB transported to entire, 25- to 35-cm-tall cotton plants ranged from 56 (clay soil, 5 mm of rain) to 226 (sandy soil, 50 mm of rain) OB/plant. In a second experiment, viral transport increased with increasing wind velocity (0, 16, and 31 km/h) and was greater in dry (-1.0 bar of matric potential) than in moist (-0.5 bar) soil. Wind transport was greater for virus in a clay soil than in silt or sand. Only 3.3 x 10(-7) (clay soil, 5 mm rain) to 1.3 x 10(-6) (sandy soil, 50 mm rain) of the OB in surrounding soil in experiment 1 or 1.1 x 10(-7) (-0.5 bar sandy soil, 16-km/h wind) to 1.3 x 10(-6) (-1.0 bar clay soil, 31-km/h wind) in experiment 2 were transported by rainfall or wind to cotton plants. This reduces the risk of environmental release of a recombinant nucleopolyhedrovirus (NPV), because only a very small proportion of recombinant virus in the soil reservoir is transported to vegetation, where it can be ingested by and replicate in new host insects.

Air Movements↗
PubMed1972

Mycoplasma: growth precipitation as a serodiagnostic method.

A serological test is described which is designated the growth precipitation test and is based on the release of diffusible compounds from mycoplasma strains. During growth of mycoplasmas on solid substrates, precipitation lines are formed with antibodies from homologous antisera independent of heat-labile serum factors. The application of the test as a serodiagnostic tool was investigated by performing a complete serological cross-test with 10 mycoplasma strains. The test was compared with the growth inhibition test, the complement fixation test, and the indirect hemagglutination test. It is demonstrated that the growth precipitation test has a good degree of specificity. The species and subspecies used here showed cross-reactions between serologically closely related strains, but these heterologous reactions occurred only after longer incubation than the homologous reactions.

Acholeplasma laidlawii↗
PubMed1974

Liquid scintillation radioassay in disposable microcentrifuge tubes: radioimmune precipitates and other applications.

A simple, economical radioassay system employing disposable polypropylene microcentrifuge tubes was developed. Plastic adapters permitted automatic operation in liquid scintillation spectrometers. Counting efficiencies of (3)H, (14)C, (32)P, and (125)I in liquid scintillation cocktails and of (32)P by Cerenkov radiation (at lower efficiency in absence of added scintillator) were comparable to those in standard vials. Multipurpose use of the microtubes made the system versatile and expedient, e.g., collection of precipitates and radioassay in the same container. Collection of radioimmune precipitates was aided by a carrier inorganic precipitate, Mg(2)P(2)O(7).

Animals↗
PubMed1982

Electrophoretic analysis of polypeptides immune precipitated from cytomegalovirus-infected cell extracts by human sera.

Serodiagnosis of cytomegalovirus (CMV) infection by complement fixation tests depends on showing a fourfold rise in antibody titer from acute- to convalescent-phase sera. Freeze-thaw and glycine-extracted, infected cell culture antigens used for these tests give markedly different titers in reactions with the same sera. In this study, we characterized the CMV-infected cell polypeptides contained in freeze-thaw and glycine-extracted antigens and identified the proteins precipitated by 23 pairs of human acute and convalescent sera. Our results were as follows. First, freeze-thaw and glycine-extracted antigens prepared from infected cells radiolabeled with [35S]methionine and subjected to electrophoresis in sodium dodecyl sulfate-polyacrylamide gels yielded similar patterns, and the bulk of the label was contained in late structural proteins and glycoproteins. Glycine-extracted preparations contained a greater proportion of soluble 66,000- and 50,000-molecular-weight proteins than did freeze-thaw antigens. Second, convalescent sera precipitated proteins migrating with apparent molecular weights of 150,000, 130,000, 110,000, 96,000, 74,000, 66,000, 50,000, 34,000, 32,000, and 25,000. Of these the 130,000-, 110,000-, 96,000-, 66,000-, 50,000-, and 25,000-molecular-weight proteins comigrated with glucosamine-labeled polypeptides. Both immunoglobulin G and M antibodies in human sera precipitated these proteins from CMV-infected cell preparations. Implications of the results for serodiagnosis of CMV infections are discussed.

Antibodies, Viral↗
PubMed1982

Precipitation of measles virus proteins by immunoglobulin G fractions containing groups of oligoclonal bands isolated from sera of patients with subacute sclerosing panencephalitis.

Groups of oligoclonal immunoglobulin G (IgG) bands were isolated from sera of patients with subacute sclerosing panencephalitis by employing preparative isoelectric focusing. Six IgG fractions containing two to three oligoclonal bands with different isoelectric points were used to precipitate the proteins from Vero cells infected with measles virus. The results showed that all of the measles virus proteins except the M protein were precipitated by all of the IgG fractions and that the precipitation of viral proteins by the fractions containing groups of oligoclonal IgG showed slightly different patterns in some sera, whereas other sera showed no significant differences. The present study indicates that oligoclonal IgGs in subacute sclerosing panencephalitis sera are not specific to individual measles virus proteins.

Antibody Specificity↗
PubMed1978

Precipitate produced by Serratia marcescens on MacConkey agar: useful diagnostic test.

The production of a precipitate by Serratia marcescens on Oxoid MacConkey agar has proven useful as a laboratory diagnostic test. This phenomenon is specific for Serratia within the Enterobacteriaceae, although precipitate production is also given by Acinetobacter anitratus and some Pseudomonas, Alcaligenes, and Aeromonas species. Precipitate production seems to be specific for certain batches of MacConkey agar, and is probably related to a specific property of some batches of bile salts.

Agar↗
PubMed1993

Hepatoerythropoietic porphyria precipitated by viral hepatitis.

Porphyria cutanea tarda (PCT), the condition resulting from a deficiency of hepatic uroporphyrinogen decarboxylase activity, is the commonest form of porphyria. Both acquired and familial form exist and are commonly associated in adults with liver disease and hepatic iron overload. The condition is extremely rare in children; most cases of childhood PCT are familial and some particularly severe cases have been shown to have a hepatoerythropoietic porphyria or homozygous uroporphyrinogen decarboxylase deficiency. A case is described of hepatoerythropoietic porphyria in which the disease was first precipitated at the age of two by a coincidental hepatitis A infection and improved as the hepatitis cleared. This paper reviews the evidence that viral hepatitis may precipitate overt PCT in children in a manner analogous to the precipitation of PCT in adults by alcohol associated liver disease.

Child, Preschool↗
PubMed1995

Precipitating causes of acid reflux episodes in ambulant patients with gastro-oesophageal reflux disease.

Previous studies of the mechanisms that precipitate acid reflux episodes have used short term hospital based measurements. A 24 hour pH and motility recording system, incorporating a sphincter monitoring device, has been developed to study naturally occurring acid reflux episodes in control subjects and patient groups with different grades of oesophagitis. Lower oesophageal sphincter relaxations related to episodes of acid reflux were common in control subjects (67% of episodes) but became more difficult to detect as the grade of oesophagitis increased (grade 0/1 - 67%, grade 2/3 - 35%, grade 4 - 13%). A variety of events that produced recognisable transdiaphragmatic pressure patterns were associated with acid reflux episodes. In control subjects 74% of acid reflux episodes were precipitated by belching but this mechanism became less evident as the grade of oesophagitis increased (grade 0/1 - 43%, grade 2/3 - 40%, grade 4 - 29%). Activities that produced a pressure gradient across the diaphragm became increasingly important as events precipitating acid reflux as oesophagitis became more severe (controls--2%, grade 0/1 - 15%, grade 2/3 - 11%, grade 4 - 22%). This study has shown the pressure events surrounding acid reflux in fully ambulant patients with gastro-oesophageal reflux disease.

Adult↗
PubMed2005

Calcium phosphate precipitation in the sarcoplasmic reticulum reduces action potential-mediated Ca2+ release in mammalian skeletal muscle.

During vigorous exercise, Pi concentration levels within the cytoplasm of fast-twitch muscle fibers may reach > or =30 mM. Cytoplasmic Pi may enter the sarcoplasmic reticulum (SR) and bind to Ca2+ to form a precipitate (CaPi), thus reducing the amount of releasable Ca2+. Using mechanically skinned rat fast-twitch muscle fibers, which retain the normal action potential-mediated Ca2+ release mechanism, we investigated the consequences of Pi exposure on normal excitation-contraction coupling. The total amount of Ca2+ released from the SR by a combined caffeine/low-Mg2+ concentration stimulus was reduced by approximately 20%, and the initial rate of force development slowed after 2-min exposure to 30 mM Pi (with or without the presence creatine phosphate). Peak (50 Hz) tetanic force was also reduced (by approximately 25% and approximately 45% after 10 and 30 mM Pi exposure, respectively). Tetanic force responses produced after 30 mM Pi exposure were nearly identical to those observed in the same fiber after depletion of total SR Ca2+ by approximately 35%. Ca2+ content assays revealed that the total amount of Ca2+ in the SR was not detectably changed by exposure to 30 mM Pi, indicating that Ca2+ had not leaked from the SR but instead formed a precipitate with the Pi, reducing the amount of available Ca2+ for rapid release. These results suggest that CaPi precipitation that occurs within the SR could contribute to the failure of Ca2+ release observed in the later stages of metabolic muscle fatigue. They also demonstrate that the total amount of Ca2+ stored in the SR cannot drop substantially below the normal endogenous level without reducing tetanic force responses.

Action Potentials↗
PubMed1991

Fatherhood, impending or newly established, precipitating delusional disorders. Long-term course and outcome.

Psychopathological reactions to fatherhood are probably not so infrequent as they would seem from psychiatric literature. In a material of paranoid psychoses, impending or newly established fatherhood was considered the main precipitating factor in 4 patients (i.e. 2.4%), compared with 7% of the female psychoses precipitated by pregnancy, childbirth or nursing. Two of the men were bachelors, insecure and inhibited, feeling compromised or helpless in the new situation. Two men were married, passive, avoidant in their personality, strongly dependent on their wives. The course and outcome varied according to the diagnoses; 2 cases having a favorable and 2 an unfavorable course and outcome. Physicians, including psychiatrists, should bear in mind that fatherhood is a possible precipitating factor for paranoid psychoses in male patients.

Adult↗
PubMed1993

Mood disorders: developmental and precipitating events.

A consecutive sample of 298 mainly non psychotic outpatients was classified according to DSM-III criteria. The differences in the reports from childhood and the precipitating events among the various subgroups of mood disorders (bipolar disorder, major depression, cyclothymic disorder, dysthymic disorder) and a residual group of patients with other mental disorders were examined. The patients in the non bipolar group reported more traumatic childhood experiences than the patients in the bipolar group. Precipitating events among patients in the group with major depression consisted more often of acute external stressors. Developmental factors and precipitating events in adulthood seem to be relevant in differentiating between the depressive disorders. The study supports the validity of the unipolar-bipolar distinction. The cyclothymic group seem to be a special variant of the major mood disorders.

Adolescent↗
PubMed2004

Gallbladder and urinary tract precipitations associated with ceftriaxone therapy in children: a prospective study.

The incidence and outcome of gallbladder and urinary tract complications in children receiving ceftriaxone therapy were evaluated prospectively. The subjects were given intravenous ceftriaxone, 100 mg/kg/day, in two divided doses infused over 20-30-minute periods, for 5-14 days. Serial abdominal ultrasonography revealed gallbladder and urinary tract precipitations in five of 35 children, three of whom had gallbladder pseudolithiasis, one gallbladder sludge and one gallbladder pseudolithiasis and urinary bladder sludge. The children who had gallbladder sludge and gallbladder pseudolithiasis with urinary bladder sludge had abdominal pain, nausea and vomiting. Three children remained symptom-free. The gallbladder precipitations were found after 4-9 days of ceftriaxone therapy, and resolved completely 7-19 days after the end of treatment. The urinary tract precipitation was found on the 5th day after cessation of ceftriaxone therapy and resolved 7 days later. Ceftriaxone-associated gallbladder pseudolithiasis, gallbladder sludge and urinary bladder sludge usually resolve spontaneously and physicians should be aware of these complications so as to avoid unnecessary therapeutic procedures.

Adolescent↗
PubMed2001

Laboratory and clinical experience in 55 patients with macroprolactinemia identified by a simple polyethylene glycol precipitation method.

PRL exists in different forms in human serum. The predominant form is little PRL (molecular mass 23 kDa) with smaller amounts of big PRL (molecular mass 50--60 kDa) and at times big big or macroprolactin (molecular mass 150--170 kDa). The frequency and clinical consequences of macroprolactinemia have not been clearly established, mainly because of difficulty in identifying these patients biochemically. This previously required the use of gel filtration chromatography, which could not be used routinely. Recently, a screening test using polyethylene glycol (PEG) has been used to identify macroprolactin in serum. Consequently, this study was designed to examine the use of PEG precipitation in the identification of patients with a predominance of macroprolactin and to establish the clinical characteristics of such a cohort. Over 12 months, 18,258 requests for serum PRL were received and of these 1225 patients had a serum PRL more than 700 mU/L. A total of 322 of these patients (26%) had a percentage recovery after PEG precipitation of less than 40%, thus indicating the presence of a predominance of macroprolactin. Fifty-five of these patients were referred for detailed clinical assessment. Symptoms typical of hyperprolactinemia were not common in this cohort. None had sustained amenorrhea and eight have had oligomenorrhea at age less than 40 yr. One had galactorrhea. All had pituitary imaging, and four had a microadenoma with none having a macroadenoma. PEG precipitation allows easy identification of macroprolactin in routine clinical practice. As the clinical consequences of this entity at this stage seem relatively benign, referral and intensive investigation of these patients may not be necessary. However, follow-up of a large cohort is required to ensure that the long-term outlook is likewise benign. This would have important implications for both patients and healthcare systems.

Adult↗