Search PubMed⌕ Search

Biomedical subjects

B Lindblom

Publications and source records attributed to B Lindblom.

At least 55 records · Page 3Linked to original sources
PubMed1997

Sex steroid receptors and human parturition.

OBJECTIVE: To investigate the correlation between sex steroid hormones and their receptors during normal and dysfunctional labor. METHODS: Myometrial and decidual biopsies along with maternal and cord blood samples were taken from women with or without labor activity. Estrogen and progesterone receptor contents in myometrium and decidua were determined by enzyme immunoassay, and hormone concentrations were analyzed by radioimmunoassay. RESULTS: In the lower segment of the uterus, the progesterone receptor concentrations of myometrium were significantly lower in oxytocin-resistant dystocia compared with those of normal labor and before labor (P < .04, P < .005, respectively). No significant difference was found in the estrogen receptors contents in the groups studied. The progesterone receptors of myometrium from the upper segment showed higher concentrations in active labor compared with those before labor and oxytocin-resistant labor (P <.01, P < .05, respectively). Estrogen receptors from the upper segment showed no significant difference in these regards. There was no difference in peripheral and myometrial sex hormone levels in the groups studied. CONCLUSION: These data suggest that, in the human, 1) oxytocin-resistant labor is associated with low levels of progesterone receptors, 2) estrogen receptors content in myometrium might have no or little relation to labor, and 3) functional labor seems not to be related to a decreased progesterone activity in the myometrium.

Adult↗
PubMed1997

Quality assurance in endoscopic surgery.

A number of operative procedures in gynecology are now being performed with the help of endoscopy, a development that was not based upon appropriate clinical trials. Quality assurance is today's challenge in gynecological endoscopic surgery. Although as a rule data from quality registers cannot be used for comparative purposes, they may guarantee a basic standard of documentation of surgical results. Quality assurance is a continuous process and a means to improve quality in general. Quality indicators are specific criteria that denote quality change and play a key role in quality programs. It is important to realize that quality in this sense may be viewed not only from the medical aspect but from a variety of perspectives including education, training and medical care.

Female↗
PubMed1996

Endothelin-1 and big endothelin-1 levels in normal term pregnancy and in preeclampsia.

To study the concentrations of endothelin-1 (ET-1) and its precursor, big ET-1, in samples of amniotic fluid, fetal urine, umbilical arterial and venous blood, retroplacental blood and maternal uterine and brachial venous blood obtained from normal and preeclamptic women. Samples were collected from 31 healthy pregnant women (16 in labor and 15 undergoing elective cesarean section) and 35 preeclamptic women (9 in labor and 26 undergoing cesarean section). Big ET-1 and ET-1 were measured by radioimmunoassay and the ET-1 to big ET-1 ratios were calculated. In preeclamptic women there was a significant elevation of ET-1 in the maternal brachial and uterine veins and of big-ET-1 in the brachial vein. The ET-1 concentrations and the ET-1/big ET ratios were significantly higher on the fetal side (i.e., in the umbilical vein and amniotic fluid) than in maternal blood, but in these sampling locations there was no difference between the normal pregnancy and preeclampsia group. A significant negative correlation (r = -0.67, P < 0.01) was found between plasma ET-1 in the umbilical vein and birth weight in the preeclamptic group. ET-1 was significantly higher in amniotic fluid than in the first neonatal urine of corresponding pregnancies (15.0 +/- 2.0 vs. 3.0 +/- 2.9 pmol/l, P < 0.05). The ET-1 and big ET-1 concentrations are significantly higher in fetal plasma and amniotic fluid than in maternal plasma, indicating increased endothelin converting enzyme activity and increased ET-1 production in utero. The elevated ET-1 concentration in maternal blood in preeclamptic compared with normal pregnant women and the negative correlation between ET-1 in the umbilical vein and birth weight suggest that ET-1 plays a pathophysiological role in preeclampsia and other conditions with intrauterine growth restriction.

Adult↗
PubMed1996

Endothelin receptor type A and B gene expression in human nonpregnant, term pregnant, and preeclamptic uterus.

OBJECTIVE: The aim of this study was to quantify the gene expression of ETA and ETB receptors within the different uterine segments of nonpregnant, normal pregnant, and preeclamptic women. STUDY DESIGN: Biopsy samples from the cervix, isthmus, and corpus uteri were obtained from eight nonpregnant, nine term pregnant, and seven preeclamptic women. The concentration of ETA and ETB receptor messenger ribonucleic acid were determined by a solution hybridization technique with complementary ribonucleic acid probes. Results are presented in counts per minute per microgram of total nucleic acid as mean +/- SEM. RESULTS: The expression of messenger ribonucleic acid encoding the ETA receptor was generally higher in the upper than in the lower uterine segment in nonpregnant, normal pregnant, and preeclamptic myometrium, whereas the opposite pattern was seen with regard to ETB. During normal pregnancy the concentrations of ETA receptor messenger ribonucleic acid in the corpus and ETB receptor messenger ribonucleic acid in the isthmus were significantly elevated compared with those in nonpregnant women. This enhanced gene expression was, however, not observed in the preeclamptic group. CONCLUSION: Our finding of segmentally differentiated endothelin receptor gene expression is compatible with a role for endothelin-1 in stimulating uterine contractions through ETA receptors during spontaneous labor and suggests a relaxing effect of the ETB receptor on the myometrium.

Adult↗
PubMed1996

A cohort study of the ocular safety of anti-ulcer drugs.

1. Recently, some cases have been reported where intravenous use of omeprazole was followed by loss of vision. We followed up a cohort of close to 140,000 persons during periods of treatment and non-treatment with five anti-ulcer drugs. 2. The relative risk of vascular disorders of the eye during use of omeprazole compared with non-use was 1.8 (95% CI 0.5-6.0). Use of other anti-ulcer drugs was associated with a similar risk of vascular disorders. The relative risk associated with current use of any anti-ulcer drug was 1.9 (95% CI 1.1-3.4). We did not find a single case of optic inflammatory disorder during treatment with any of the five anti-ulcer drugs. 3. These results do not suggest a major increased risk for vascular or inflammatory disorders of the eye associated with use of omeprazole or other anti-ulcer drugs.

Adult↗
PubMed1996

Causes of vitreous hemorrhage.

It is often a challenge for the ophthalmologist to find the underlying cause of a vitreous hemorrhage. Unless clinical signs clearly point in another direction, the first suspicion should always be a posterior vitreous detachment causing a retinal tear. The other two major causes, diabetic retinopathy and retinal vein occlusion, remain common complications in spite of recent years' improvement in retinal treatment. Macroaneurysm is one of the most often overlooked causes of vitreous hemorrhage. An ocular tumor sometimes presents with a vitreous hemorrhage. In all cases of dense vitreous hemorrhages, the use of diagnostic ultrasonography is mandatory.

Animals↗
PubMed1996

Role of articulation in speech perception: clues from production.

The relative roles played by signal properties and nonsignal information in speech perception are first examined. The evidence strongly suggests that phonetic percepts are never knowledge-innocent records of the raw signal. That conclusion is drawn not only about "higher" levels of language processing, but is seen to apply also to the perception of elementary phonetic stimuli. A review of a broad range of facts about production highlights the fact that speech production is adaptively organized. That circumstance suggests that the signal does not encode articulatory or acoustic/auditory invariants, but plays the role of supplementing the multimodal information already in place in the listener's speech processing system. It is accordingly proposed that phonetic signals are not invariants wrapped in "noise," but are products of listener-dependent adaptations that transform speech patterns in principled and, therefore, interpretable ways. Do listeners form speech percepts by way of intermediate articulatory representations? There seem to be strong both theoretical and methodological reasons to doubt that they do.

Humans↗
PubMed1996

Effects of endothelin-1 and the ETA receptor antagonist BQ-123 on resistance arteries from normal pregnant and preeclamptic women.

OBJECTIVE: To compare the effect of endothelin on isolated resistance arteries from different vascular beds in normal and preeclamptic women before and after pretreatment with the ETA receptor antagonist BQ-123. MATERIALS AND METHODS: Resistance arteries from myometrial and omental biopsies obtained at cesarean section of normal pregnant and preeclamptic women were dissected and mounted in organ baths for recording of isometric tension. The contractile response to endothelin-1 in presence and absence of BQ-123 was recorded. RESULTS: Endothelin-1 induced similar concentration-dependent contractions in all arteries investigated. In women with preeclampsia the contractile response induced by endothelin-1 was significantly higher in omental as compared to myometrial vessels. Pretreatment with BQ-123 significantly shifted the concentration-response curve to the right but only reduced the maximum contractile response in omental vessels. CONCLUSION: Endothelin-1 is a potent constrictor of resistance arteries from different vascular beds in normal pregnancy and preeclampsia. The contractile effect is at least in part mediated by ETA receptors, since it was significantly reduced after pretreatment with BQ-123. In preeclamptic but not in normal pregnant women the response to endothelin-1 was reduced in myometrial as compared to omental arteries, possibly secondary to receptor down regulation.

Adult↗
PubMed1995

A cost-effectiveness study of a randomised trial of laparoscopy versus laparotomy for ectopic pregnancy.

We compared the cost-effectiveness of therapeutic laparoscopy and open laparotomy for treatment of laparoscopically diagnosed ectopic pregnancy. Clinical outcomes of ectopic pregnancy treatment were based on results of a randomised trial done between 1987 and 1989 at Sahlgrenska University Hospital (Göteborg, Sweden). We estimated costs for inpatient and follow-up care of ectopic pregnancy by the two methods. Observed resource use (eg, procedure duration) was multiplied by 1992 estimates of resource unit cost (eg, cost per minute of laparoscopy time), based on detailed internal cost accounting data from Huddinge University Hospital. By specified criteria, the initial procedure eliminated trophoblastic activity without major complications in 81% (95% CI: 68-90) of 52 laparoscopy patients, versus 95% (85-99) of 57 laparotomy patients. Residual trophoblast or complications were successfully treated in all remaining patients. Mean simulated costs (standard error) for the overall laparoscopy strategy were 28,058 (1780) Swedish kronor versus 32,699 (1080) kronor for laparotomy (p = 0.03). In the baseline simulation and most sensitivity analyses, laparoscopy produced final outcomes equivalent to those of laparotomy at lower costs. As laparoscopic outcomes improve, this newer approach should become increasingly preferable.

Cost-Benefit Analysis↗
PubMed1995

Lp(a) lipoprotein, IgG, IgA and IgM antibodies to Chlamydia pneumoniae and HLA class II genotype in early coronary artery disease.

The associations previously found between lipoprotein(a) (Lp(a)) levels and atherosclerotic disorders, diabetes, rheumatoid arthritis and renal diseases suggest that Lp(a) may be involved in autoimmune reactions. The relation found between Lp(a) levels and the HLA class II genotype in males with early coronary artery disease (CAD) further support that assumption. It was suggested that an autoimmune process, perhaps triggered by a concomitant intracellular infection may occur especially in patients with inherited high Lp(a) levels in combination with certain inherited HLA class II genotypes. In this study a Chlamydia pneumoniae IgG titer > or = 32 was significantly more common (P = 0.036) in CAD patients than in matched controls. This is in agreement with previous reports by other investigators. In addition, an IgG titer > or = 256 in combination with an Lp(a) level > or = 120 mg/l was found to occur significantly more often (P = 0.011) in male patients than in male controls. Certain HLA class II DR genotypes in combination with high Lp(a) levels and C. pneumoniae titers occurred more frequently in both male and female patients than in controls. Some combinations were very common in male patients, and the difference in comparison with male controls was highly significant.

Antibodies, Bacterial↗
PubMed1995

Flanking region sequences and internal repeat structure of the pYNH24 (D2S44) 2 kbp insert analyzed by polymerase chain reaction and partial digestion with RsaI.

The 2 kbp YNH24 pUC18 insert was partially sequenced, amplified with fluorescence-labeled primers, and characterized by incomplete digestion with the restriction enzyme RsaI. A characteristic RsaI profile with one restriction site in each repeat unit was obtained when the fragments were analyzed on a DNA sequencer. We developed this procedure with the specific aim of analyzing the internal repeat structure in recombinant alleles often observed in the YNH24 variable number of tandem repeat system (D2S44). Nonetheless, it should also be possible to apply the method when analyzing other tandem repeats, even when little information regarding their sequences is available. In addition, when the repeat array is amplified, either a 5' or a 3' fluorescence-labeled primer can be used to enable analysis from both directions of fairly long (> 3.6 kbp) alleles. The RsaI fragments obtained by partial digestion of the amplified pYNH24 insert corresponded well to the RsaI sites found in the sequenced regions. The 5' flanking region contained eight 30-34 bp sequences similar to the repeat unit and also several RsaI sites, whereas only a few RsaI sites and no repeat units were found in the 3' flanking region. Twenty-five consecutive RsaI sites were revealed, in the center of the pYNH24 insert, indicating a region with strictly repeated core sequences; this repetitive block comprised less than half of the total insert. Two approximately 2.24 kbp HinfI alleles from two different heterozygous individuals were found to have identical internal structure, which was very similar to that of the insert although it exhibited only 15 RsaI repeats.

Alleles↗
PubMed1995

A prospective study of dense spontaneous vitreous hemorrhage.

PURPOSE: We studied the incidence of vitreous hemorrhage in a well-defined population to determine the underlying causes of such hemorrhages. METHODS: We prospectively studied all eyes with dense spontaneous first-time vitreous hemorrhage during a 2 1/2-year period in the greater Göteborg area (542,000 inhabitants). Follow-up time was one year. RESULTS: Ninety-four patients (95 eyes) were included, corresponding to a yearly incidence of seven cases per 100,000 inhabitants. Because of demographic factors and the organization of Swedish ophthalmologic care, we believe that this is close to the true incidence. The cause of vitreous hemorrhage could be verified in all but four eyes but frequently not until late in the follow-up period. The most common underlying cause was vitreous detachment and traction to a retinal vessel (39 eyes). In 28 of these eyes a retinal tear was also present. Five of these eyes developed a retinal detachment. In 19 eyes, bleeding was caused by proliferative diabetic retinopathy. This figure was relatively smaller than in previous studies. Retinal vein occlusion was the cause of hemorrhage in 15 eyes. Retinal macroaneurysm (seven eyes) was an easily overlooked cause, often diagnosed late in the follow-up period. CONCLUSIONS: Because of the common diagnostic difficulties and the frequent need for laser treatment, vitrectomy, or both, it is recommended that eyes with vitreous hemorrhage be followed up in centers with ultrasonographic and surgical expertise.

Adult↗
PubMed1995

Effects of hyperosmolar glucose, prostaglandin-F2 alpha and 15-methyl-prostaglandin-F2 alpha on human placental cells in vitro.

The objective of this study was to assess the ability of certain drugs, used for local injection therapy of ectopic pregnancy, to suppress the activities of cultured human placental cells. Placental cells from legal first trimester abortions were prepared by collagenase treatment and density gradient centrifugation. The cells were exposed to hyperosmolar glucose (500 mg/ml), 15-methyl-prostaglandin-F2 alpha (15-m-PGF2 alpha; 10(-7) to 10(-3) mol/l) and prostaglandin-F2 alpha (PGF2 alpha; 10(-5) to 5 x 10(-3) mol/l) for 30 min on days 2-4 after seeding. The effects on the secretion of human chorionic gonadotrophin (HCG) and progesterone, as well as on the protein content per culture well, were measured. Hyperosmolar glucose was the most effective drug and caused a marked decrease of the protein content in the culture wells and a reduction of progesterone secretion. Of the two prostaglandins, only 15-m-PGF2 alpha affected the viability of the cells and reduced the protein content of the wells. The clinical effectiveness of the two groups of drugs seems to be similar but certain in-vitro effects are different. Thus in vivo they may act on different target tissues. Against this background, the combination of hyperosmolar glucose and prostaglandins might be an interesting approach for local injection therapy for tubal pregnancy.

Carboprost↗
PubMed1995

HLA phenotypes and severe Rh(D) immunization.

Blood samples from 24 Rh(D) immunized women were analyzed for antibody titers and quantification of anti-D. The HLA-DR and -DQ polymorphisms were identified as RFLP. In 11 women with titers 16-256 the HLA-DQB1 allele *0201 was found in 18%, i e as in a reference population. In 13 women with titers > or = 512 the HLA-DQB1 allele *0201 was found in 85% indicating a correlation between severe Rh(D) immunization with high titers/quantification values and the DQB1 allele *0201. In this group the fetus was severely affected by the immunization and treatment during pregnancy was frequently needed. HLA phenotyping of women known to have anti-D antibodies early in pregnancy seems to be an effective way to assess the probability of severe hemolytic disease of the newborn.

Alleles↗
PubMed1995

Confocal fundus imaging with a scanning laser ophthalmoscope in eyes with cataract.

AIMS/BACKGROUND: The study aimed to determine the influence of increased intraocular light scatter on the contrast in scanning laser ophthalmoscope (SLO) images and to examine to what extent SLO images can visualise the fundus through media opacities due to cataract. METHODS: Intraocular light scatter was estimated from measurements of letter contrast sensitivity before and after cataract surgery in five eyes. SLO images were obtained before and after surgery using confocal apertures of 1, 2, 4, and 10 mm, at laser wavelengths of 633 and 780 nm. Visibility of the fundus was determined by measurements of retinal contrast. SLO images were compared with standard fundus photographs. RESULTS: SLO images obtained before surgery revealed details of the retina that were unresolvable in the fundus photographs because of light scattering. By using one of the three smallest apertures, image contrast was further improved. However, no simple relations between aperture size, estimated light scatter, and image contrast could be found. CONCLUSION: SLO imaging was found to be superior to fundus photography for viewing the retina in eyes with cataract. Owing to the inhomogeneous nature of cataracts, the optimal choice of confocal aperture and laser wavelength is not simple and must be individualised.

Aged↗
PubMed1995

Effects of atrial natriuretic peptide and cyclic guanosine monophosphate on isolated human myometrial arteries preconstricted by endothelin-1.

In the present in vitro study we investigated the possible vasorelaxing effect of atrial natriuretic peptide (ANP) and cyclic guanosine monophosphate (cGMP) on small intramyometrial arteries precontracted by endothelin-1 (ET-1). Myometrial biopsies from normotensive pregnant women were obtained during cesarean section and arteries of resistance vessel size were dissected and mounted in a tissue chamber for isometric registration of contractile tone. In arteries preconstricted with ET-1 (10(-8)M), ANP produced a concentration-dependent relaxation of 19 +/- 5% (mean +/- SEM) and 27 +/- 7% at concentrations of 10(-7) and 3 x 10(-7) M, respectively. cGMP induced a relaxation of 13 +/- 2, 18 +/- 3, 25 +/- 4 and 30 +/- 7% at concentrations of 10(-5), 10(-4), 3 x 10(-4) and 10(-3) M, respectively. Pretreatment with ANP did not attenuate the contraction produced by ET-1. We suggest that ANP may have a vasodilating effect on preconstricted human uteroplacental vessels. It also provides evidence for the role of other endogenous or exogenous vasodilators acting via cGMP-dependent mechanisms in the counteraction of ET-1-induced contraction of the myometrial resistance vessels during pregnancy.

Arteries↗