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Adolescents' Growing Sensitivity to Psychosocial Stressors: Evidence From Two Decades of Health Behaviour in School-aged Children (HBSC) Data in the Nordic Countries.

PURPOSE: We tested a perception-based explanation for rising psychosomatic complaints among adolescents in the Nordic countries. Specifically, we examined whether adolescents have become more sensitive to psychosocial stressors, reflected in stronger associations between stressors and psychosomatic complaints in 2022 than in 2002. METHODS: Data were drawn from the 2002 to 2022 waves of the Health Behaviour in School-aged Children survey among 15-year-olds in five Nordic countries (N = 7,263 in 2002 and 6,739 in 2022). Psychosomatic complaints were examined in relation to stressors in the following three domains: interpersonal relationships, school-related strain, and body- and activity-related factors. Moderated regression analyses tested whether associations between stressors and complaints differed between survey years. Sex and perceived family finances were included as covariates. RESULTS: Four of five psychosocial stressors showed stronger associations with psychosomatic complaints in 2022 than in 2002. Perceived poor family finances, although less prevalent in 2022, were more strongly related to complaints. Girls consistently reported higher levels of psychosomatic complaints, and the association between school pressure and complaints was stronger among girls. DISCUSSION: Although several psychosocial stressors declined in prevalence, their associations with psychosomatic complaints strengthened over time. These findings suggest that rising complaints may reflect changes in how psychosocial stressors are linked to adolescents' psychosomatic symptoms, rather than increases in exposure to those stressors. This shift highlights the importance of considering how adolescents interpret and respond to everyday stress when addressing population trends in mental health.

Humans

Albumin density gradient purification of canine hemopoietic blood stem cells (HBSC): long-term allogeneic engraftment without GVH-reaction.

Long-term repopulation of the blood-forming organs of dogs, conditioned by wholebody X-irradiation (1200 R midplane dose), was achieved by transfusion of cryopreserved allogeneic blood mononuclear cells (MNC) without causing graft-versus-host-reaction (GVH-R). Donor and recipient dogs were DL-A identical, MLC-negative, no siblings, non-related. The blood stem cells (CFUc) were procured by a 3- to 4-hour continuous-flow leukapheresis. To increase the CFUc concentration in the peripheral blood, dextran sulfate (DS) was administered intravenously beforehand. About 1 x 10(10) MNC, among them about 1 x 10(7) CFUc, were collected and further segregated using a discontinuous albumin density gradient. Less dense cells were to be found in the upper part of the gradient (fraction 2). These cells included most of the CFUc, enriched by a factor of between 275 and 1730 compared to their concentration in the peripheral blood beforehand. After cryopreservation, these cells, when transfused into lethally irradiated dogs, completely repopulated the marrow and lymph nodes, caused no GVH-R and allowed long-term survival. These dogs received no immunosuppressive therapy, either before or after transfusion. More dense MNC were to be found in fraction 3; their transfusion caused a severe GVH-R, followed quickly by death. Fraction 4 was rich in lymphocytes and poor in CFUc. The transfusion of these cells produced a selective plasma-cell hyperplasia of the lymph nodes but failed to repopulate permanently the marrow. The reappearance of the different cell lineages in the marrow and in the peripheral blood after conditioning and transfusion of these cells produced a selective plasma-cell hyperplasia of the lymph nodes but failed to repopulate permanently the marrow. The reappearance of the different cell lineages in the marrow and in the peripheral blood after conditioning and transfusion of the segregated MNC is described in detail.

Animals

Is There a Difference in Occurrence of Complications Between Adults With Hemoglobin SS and Hemoglobin SC Disease: An Extended Systematic Review.

Sickle cell disease (SCD) is characterized by both acute and chronic complications. The clinical manifestation of these complications differs between genotypes. Given the large amount of research already published, this systematic review aims to offer a complete overview of types of sickle cell complications between adults in the most common genotypes Hemoglobin SS (HbSS) and Hemoglobin SC (HbSC), putting options for further research into perspective. An extensive literature search was performed to study all available evidence on these complications. This review was performed according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) statement guidelines, and was performed on January 2, 2024. A total of 710 references were identified. After careful screening, 521 records were excluded based on title and abstract and other exclusion criteria. In total, 158 articles were excluded after full-text assessment. Our analysis of 31 studies highlights key differences in complications between HbSS and HbSC genotypes in sickle cell disease (SCD). Vaso-occlusive crises (VOCs) remain the most common acute complication in both genotypes. HbSS patients experience more frequent VOCs, while HbSC patients generally have a milder clinical course when it comes to acute complications. Chronic complications, particularly in the ocular and pulmonary systems, are more prevalent in HbSC patients. However, as acute complications are more common in HbSS and chronic complications more common in HbSC, both genotypes face progressive organ damage due to recurrent ischemic injury and inflammation.

Humans

Sickle cell syndromes. I. Hemoglobin SC-alpha-thalassemia.

Hematologic and globin synthesis studies were performed in a black American family in which the genes for alpha-thalassemia and hemoglobins (Hb) S and C were segregating. The following distribution of these abnormalities was found: father, sickle cell trait + alpha-thalassemia; mother, HbC trait + alpha-thalassemia, propositus, HbSC + alpha-thalassemia; older sibling, alpha-thalassemia trait; and younger sibling, hemoglobin H disease. The child with HbSC-alpha-thalassemia demonstrated more severe anemia and a more hemolytic picture than is typical of HbSC disease. Her erythrocytes exhibited decreased osmotic fragility in comparison with HbSC erythrocytes, but had an indistinguishable oxygen equilibrium curve and 2, 3-diphosphoglycerate (2, 3-DPG) level. Erythrocyte sickling in the patient, however, was significantly reduced, with less than 35% sickle forms observed at nearly complete oxygen desaturation. The sibling with hemoglobin H disease exhibited 26% Bart's (gamma4) hemoglobin at birth, a level comparable with that seen in infants with HbH disease in Far Eastern populations. At age 5 months typical findings of mild hemoglobin H disease appeared, with HbH making up 6.5% of the total hemoglobin.

Anemia, Sickle Cell

Regional and temporal variation in oscillatory blood flow in sickle cell disease.

We examined 55 patients with sickle cell anemia (HbSS) and 16 with hemoglobin SC disease (HbSC) to ascertain the presence of periodic microcirculatory flow (PMF) using laser-Doppler velocimetry. Forty-nine percent of patients with HbSS and 12.5% of HbSC patients had PMF on at least one occasion and in at least one site. The presence of PMF could be correlated with an increase in packed cell volume (PCV) and hemoglobin in individuals with HbSS and an increased white blood cell and platelet count in patients with HbSC. PMF may result from complex interactions among perfusion pressure, capillary tone, and the numbers and intrinsic properties of formed blood elements.

Anemia, Sickle Cell

Differential expression of two sodium channel subtypes in human brain.

Two partial human brain sodium channel cDNA sequences (designated HBSC I and II) have been cloned and mapped to chromosome 2q23-2q24 by chromosome microdissection-PCR (CMPCR). The distribution of HBSC I and II mRNA in human brain was studied by means of a novel approach based on the ligase detection reaction. These studies demonstrate that HBSC I and II mRNA is heterogeneously distributed in brain, and that the relative ratio of the two forms can vary as much as 7-fold between different regions.

Amino Acid Sequence

Sickling-induced binding of autologous IgG to erythrocytes heterozygous for sickle hemoglobin.

This study reports that sickling-induced increased autoantibody binding can be demonstrated in varying degrees for deoxygenated S/beta-thalassemic (2-fold) and hemoglobin-SC (1.2-fold) erythrocytes as compared with oxygenated paired samples. In contrast, HbAS erythrocytes deoxygenated in autologous plasma exhibited less than 2% morphologic sickling and no increased IgG binding as compared with control samples. Sickling in the presence or absence of plasma increased the IgG binding capacity of S/beta-thalassemic erythrocytes, comparable to previous findings for HbSS erythrocytes, while increased IgG binding to HbSC erythrocytes was detected only after deoxygenation in plasma. It is concluded that specific IgG binding to deoxygenated S/beta-thalassemic RBCs results from subtle permanent sickling-induced alterations of the membrane surface, while IgG binding to HbSC erythrocytes sickled in plasma results from transitory membrane changes. These findings suggest that sickling in vivo will produce cumulative autoantibody binding to S/beta-thalassemic erythrocytes, a process which could lead to immune-mediated erythrocyte destruction. In contrast, comparatively small fractions of the autoantibody bound to HbSC erythrocytes in vivo would result from sickling-induced membrane alterations. These studies indicate that sickling-associated autoantibody binding in vivo will not occur for sickle cell trait (HbAS) erythrocytes protected by plasma.

Anemia, Sickle Cell

Laboratory profile of sickle cell disease: a cross-sectional analysis. The Cooperative Study of Sickle Cell Disease.

We have collected steady-state laboratory data for over 2600 patients, age 2 years and over, with sickle cell anemia (HbSS), HbSC disease, and HbS-beta(+)-thalassemia. The packed cell volume (PCV) is lower in males than in females until 17 or 18 years of age in HbSS and ages 13 to 15 in HbSC, but then becomes consistently higher in males. After age 40, the PCV falls in HbSS. The steady-state leukocyte count in HbSS is higher than that in normals, blunting the utility of this measurement in the assessment of infection. In HbSC and HbS-beta(+)-thalassemia, the leukocyte counts are more often within the range of normal. Platelet counts in HbSS are often found to be above normal and show a downward trend with age. There is a progressive rise in creatinine with age. In HbSS, this rise begins at age 14 and may be accounted for by the increased muscle mass that occurs with puberty. The further deterioration of renal function in patients over 20 may be a result of the known adverse effects of sickle cell disease upon the kidney. Our data provide a basis to compare perturbations caused by intercurrent complications and new therapies, as well as to contrast with similar information from other populations of patients with sickle cell disease.

Adolescent

Comparative studies of live neonates in maternal sickle cell haemoglobinopathy in Ghana.

This study assessed the current status of live neonates born to sickle cell mothers when compared with those of normal (control) women. Birth weight, placental weight, fetoplacental ratio, and gestational age for live neonates in singleton births by twenty-nine haemoglobin SS (HbSS), fifty-two haemoglobin SC (HbSC), and fifty-one (normal) haemoglobin AA (HbAA) mothers were statistically compared. Neonates of HbSS mothers had a statistically lower than normal mean birth weight and gestational age, but only a shorter mean gestation significantly distinguished those of the HbSC and HbAA mothers. Inferentially, neonates delivered by HbSS women were both underweight and preterm, whereas those of HbSC women were preterm but not underweight, and apparently large for gestational age (LGA). No statistical differences were found between neonates in terms of placental weights or fetoplacental ratios.

Anemia, Sickle Cell

Chronic leg ulcers in sickle cell disease: experience in Ibadan, Nigeria.

The prevalence of chronic leg ulcers was investigated in 872 adults with sickle cell disease (SCD) (630 HbSS and 242 HbSC) at Ibadan, Nigeria. The incidence was 7.5% in HbSS and 1.7% in HbSC patients. The sex ratio in HbSS was 2:1 in favour of males, and three of the four HbSC were females. Ulcers were sited around the ankles in more than 70% of the patients. The duration of the ulcers varied from less than 1 year to more than 20 years. There was no bias for social class. Response to therapy, including autologous skin graft, was poor.

Adolescent

The hemoglobinopathies and pregnancy in Lagos.

Thirty-four patients with abnormal hemoglobin were studied through 42 pregnancies under one obstetrician. There were 30 patients with sickle cell anemia (HbSS), two with sickle cell hemoglobin C disease (HbSC) and two with homozygous hemoglobin C disease (HbCC). There were 39 live births (including one pair of twins), and four perinatal deaths. The patients with HbSC and HbCC had five uncomplicated pregnancies and deliveries. Of the 36 pregnancies in patients with HbSS one aborted at 12 weeks. Intra-uterine growth retardation (14.3%) and pregnancy-induced hypertension (14.3%) were the most serious pregnancy complications. No patient had more than one crisis. Only one out of the 10 patients transfused needed more than two units of blood throughout pregnancy. The mean gestation at delivery was 37.5 +/- 3.2 (S.D.) weeks. The mean birth weight was 2.7 +/- 0.6 (S.D.) kg. The perinatal mortality was 114.3 per thousand live births and there was one maternal death.

Adult

Detection of abnormal haemoglobin by capillary electrophoresis and structural identification.

Haemoglobin obtained from a male adult Ghanian with retinopathy, which was probably caused by haemoglobinopathy was analysed by capillary electrophoresis (CE) for clinical diagnosis. Two major peaks, which were in the ratio of nearly one, were detected. The elution times of these peaks (HbXI and HbXII) were faster than that of normal haemoglobin (HbA). The existence of two different abnormal types of haemoglobin was clear in the patient blood. The following sequence analysis revealed that the first peak (HbXI) was HbC and the second (HbXII) was HbS on the electropherogram, and that the patient was a heterozygote of HbS and HbC (HbSC disease). One of the diagnostic processes in a haemoglobin disease was shown by the combined use of CE, HPLC and a protein sequencer.

Adult

Pregnancy in hemoglobin sickle cell patients at the University College Hospital, Ibadan.

A retrospective review of pregnancy outcome in hemoglobin (Hbsc) patients managed at the University College Hospital, Ibadan over a 5-year period (1984-1988) was carried out. The main antenatal complications included anemia (51.2%), bacterial infection (22.0%), bone pain crisis (7.3%) and preeclampsia (2.4%). Intrapartum complications included anemia (29.2%), bone pain crisis (12.2%) and pseudotoxemia (4.9%). The maternal and perinatal mortality rate were 48 and 195 per 1000, respectively. The duration of labor and operative delivery rate were not different from the general population.

Adult

Hemoglobin ontogenesis: test of the gene excision hypothesis.

The gene excision hypothesis of hemoglobin ontogenesis was tested in persons with HbSC disease, with the use of monospecific fluorescent antibodies for the identification of hemoglobins S, C, and F in individual erythrocytes. The results are incompatible with the prediction that only one gamma- or beta-globin gene may be active in any single chromosome and provide further evidence for incomplete repression of gamma-globin genes lying cis to active beta-globin genes.

Fetal Hemoglobin

Value of serum ferritin estimation in sickle cell anaemia.

In a group of 35 children with sickle cell anaemia serum ferritin concentration ranged from 70 to 2460 microgram/l (mean 367, median 180 microgram/l). This was significantly higher than the ferritin levels (range 8-101, mean 34, median 30 microgram/l) in a group of 63 normal control children of the same age group. 30 (86%) of the sickle cell children showed serum ferritin levels greater than 101 microgram/l, and 2 (6%) levels greater than 1000 microgram/l. 7 of the patients had not been transfused before this study. Their serum ferritin levels were all raised and showed a significant correlation with age but not with haemoglobin level. In the remainder of the patients the serum ferritin bore no significant correlation with age, haemoglobin level, or number of units of blood transfused. 2 children with HbSC disease had levels within the control range. Since patients with sickle cell anaemia have an increasing chance of long survival, we suggest that serial estimations of their iron status be made by means of serum ferritin assay in order to determine which patients are accumulating excessive iron.

Adolescent

Penicillin prophylaxis in children with sickle cell disease in Brent.

OBJECTIVE: To assess compliance with oral penicillin prophylaxis in children with sickle cell disease and identify possible reasons for poor compliance. DESIGN: Closed questionnaires given to parents of children with sickle cell disease and general practitioners in Brent. Urine samples from 23 children were tested for penicillin. SETTING: Paediatric haematology clinic, Central Middlesex Hospital, and general practices in Brent. SUBJECTS: 50 children (aged less than or equal to 16) attending clinic with sickle cell disease over six months (33 HbSS, 12 HbSC, five HbS beta thalassaemia). 30 general practitioners: 15 with the greatest number of patients with sickle cell disease on the Brent register; 15 selected randomly from family practitioner committee's list. MAIN OUTCOME MEASURES: Reported compliance with and awareness of importance of penicillin prophylaxis. Results of urine tests for penicillin. RESULTS: 31 parents claimed that their children received penicillin every day and 19 that they received it most days (greater than or equal to 5 days a week). Penicillin was detected in only 10 of 23 urine samples tested. Parents and doctors seemed not to appreciate the importance of treatment: only eight parents were aware of the risk of death if penicillin were discontinued, and 16 doctors were unaware that regular penicillin prophylaxis prevents pneumococcal septicaemia and death in these children. CONCLUSIONS: Education for families with children with sickle cell disease must be improved. Specialised information and training are needed for doctors working in areas with a high prevalence of the disorder.

Administration, Oral