Stress, menopausal status and nocturnal blood pressure dipping patterns among hypertensive women

BACKGROUND:

A less than 10% decline in blood pressure during the night is known as a nondipping blood pressure (BP) pattern. Nondipping BP has been shown to be associated with target organ damage and poorer cardiovascular outcomes. Additionally, some evidence suggests that hypertensive nondipping women are at greater risk for target organ damage than hypertensive nondipping men.

OBJECTIVE:

To determine whether stress, demographics, menopausal status or sleep quality are associated with nondipping BP among hypertensive women.

METHODS:

A cross-sectional study design was used to describe the relationship between stress and dipping status among a sample of hypertensive women and to describe the sample by age, ethnicity, marital status, menopausal status, current medications and sleep quality.

RESULTS:

The study sample consisted of 47 women (mean [± SD] age 57±13.9 years) with essential or office hypertension who underwent 24 h ambulatory BP monitoring, and completed stress and sleep quality measurements. Thirty-one women (66%) were classified as dippers and 16 (34%) were classified as nondippers. Nondippers were older (P=0.04), postmenopausal (P=0.003) and had lower stress scores (P=0.02) than their dipper counterparts. Postmenopausal status significantly predicted nondipping (OR 16; 95% CI 1.9 to 136.4).

CONCLUSION:

These findings were of interest given that some women had a nondipping BP pattern and significantly lower stress scores. It is possible that there are fundamentally different physiological mechanisms that explain this nondipping phenomenon. In the future, the identification of specific hemodynamic mechanisms associated with nondipping could potentially influence the choice of antihypertensive treatment regimens for nondipper hypertensive patients.     

Brain swelling and ischaemia in Kenyans with cerebral malaria

Computed tomography was performed on 14 unconscious Kenyan children recovering from cerebral malaria (seven of whom had another scan 12-120 days later) to elucidate the cause of intracranial hypertension and neurological sequelae. Brain swelling, defined as a loss of cerebrospinal fluid spaces, was documented in six children, while a further two had conspicuously small ventricles only. There was severe intracranial hypertension in the two children with definite brain swelling in whom intracranial pressure was monitored. There was no evidence of acute hydrocephalus or vasogenic oedema. Four children with brain swelling also had widespread low density areas suggestive of ischaemic damage. The patterns of damage were not uniform but were consistent with a critical reduction in cerebral perfusion pressure (which was documented in the two in whom this was monitored), hypoglycaemia, or status epilepticus. All four had serious neurological sequelae. These data suggest that brain injury in cerebral malaria may be due in part to secondary systemic and intracranial factors as well as to the direct effect of intravascular sequestration.     

Science, medicine and phenylketonuria

Science addresses ignorance; medicine uses facts. The scientific approach to phenylketonuria (PKU) led to the discovery of its causes, both ultimate (allelic heterogeneity at the PAH locus) and proximate (dietary phenylalanine), the proximal phenotype (phenylalanine hydroxylase deficiency), the associated metabolic phenotype and the major distal phenotype (impaired cognitive development and neuropsychological function) for which the pathogenesis is still being investigated. By applying knowledge through newborn screening, early diagnosis and treatment, the brain disease of PKU has been greatly ameliorated. The population approach, which converted incidence into cases, revealed genetic heterogeneity in hyperphenylalaninemia involving four other loci, controlling cofactor (BH₄) synthesis and recycling, and non-random geographic distribution of mutant PAH alleles of which more than 170 were known in April 1994. Various mechanisms including founder effect, genetic drift, hypermutability and selection (perhaps) explain the polymorphic aggregate frequency (∼ 0.01) and spectrum of PKU mutations in human populations.     

Peripheral blood stem cells used to augment autologous bone marrow transplantation

Peripheral blood stem cells (PBSC) were used to augment autologous bone marrow transplantation (ABMT), aiming to hasten engraftment after high dose treatment in a group of heavily pretreated patients. PBSC were obtained by leukapheresis during the rebound after standard chemotherapy. In 11 patients aged 7-17 years, high dose chemotherapy consisted of busulphan 16 mg/kg orally with melphalan 160 mg/m2 intravenously for seven patients, and melphalan 200 mg/m2 intravenously alone for four. The median number of granulocyte-macrophage colony forming units in the reinfused PBSC was 3.42 x 10(4)/kg (3.03-18.01) and bone marrow 12.4 x 10(4)/kg (4.16-28.6). Neutrophil recovery to > or = 0.5 x 10(9)/l and platelet transfusion independence occurred at a median of 14 days (11-18) and 22 days (9-84) respectively. In five patients the early engraftment was transient with neutrophils again dropping below 0.5 x 10(9)/l then slowly recovering. There was one toxic death due to sepsis. PBSC harvesting in these children was undertaken without interrupting routine chemotherapy and without the use of bone marrow growth factors. In some patients PBSC failed to influence engraftment and the use of combined chemotherapy and growth factor priming for PBSC collection may give improved results.     

HPLC法测定冬凌草萜含片中冬凌草甲素的含量

目的：对冬凌草萜含片中的冬凌草甲素进行含量测定。方法：采用ＨＰＬＣ法,以Ｃ１８－ＯＤＳ为色谱柱,甲醇－水（５５：４５）为流动相,检测波长为２４２ｍｍ。结果：回收率为９８．２３％,ＲＳＤ为２．１２％。结论：该方法简便、可靠,适合冬凌草及其制剂的质量控制。     

Genotypes of glutathione transferase M1 and P1 and their significance for lung DNA adduct levels and cancer risk

The A-G polymorphism at codon 104 in the glutathione S-transferase P1 (GSTP1) gene was examined in 138 male lung cancer patients and 297 healthy controls. The patients had significantly higher frequency of the GG genotype (15.9%) and a lower frequency of AA (38.4%) than the controls (9.1% and 51.5%, respectively). The level of hydrophobic DNA- adducts were determined in lung tissue from 70 current smokers. Patients with the GG genotype had a significantly higher adduct level than patients with AA (15.5 +/- 10.2 vs 7.9 +/- 5.1 per 10(8) nucleotides, P = 0.006). We also analyzed the deletion polymorphism in the GSTM1 gene in 135 male patients and 342 controls. The patients were stratified according to histology, smoking dose, age, adduct level and mutational types found in the tumors (Ki-ras and p53 genes). The results consistently indicated that the GSTM1 null genotype was associated with a slightly increased lung cancer risk. When the combined GST M1 and P1 genotypes were examined, patients with the combination null and AG or GG had significantly higher adduct levels than all other genotype combinations (P = 0.011). The distribution of combined genotypes was also significantly different in cases and controls, mainly due to increased frequency of the combination GSTM1 null and GSTP1 AG or GG among patients.      

Preimplantation hormonal differences between the conception and non- conception menstrual cycles of 32 normal women

We compared daily urinary concentrations of oestrogen and progesterone metabolites in paired menstrual cycles (conception and non-conception) from 32 women. Volunteers with no known fertility problems were enrolled in the study at the time they began trying to become pregnant. They collected first-morning urine specimens and kept daily records of menstrual bleeding and sexual intercourse for 6 months or until they became clinically pregnant. Intercourse in non-conception cycles was close to the time of ovulation so that failure to conceive was caused by factors other than poorly timed intercourse. Compared with non- conception cycles, conception cycles had a steeper early luteal rise in progesterone and higher mid-luteal oestrogen and progesterone concentrations. These hormonal characteristics may be markers of better quality cycles, but because all these differences were in the luteal phase, we cannot rule out the possibility that the preimplantation embryo had stimulated early increases in steroid production. We propose an analysis strategy that could help support or refute the importance of preimplantation embryonic signalling, but our small sample size limits our own conclusions about this mechanism.      

Application of autologous peripheral blood stem cell transplantation in children with malignant tumor

Objective To investigate if low dose total body irradiation (TBI, 6.0-9.0 Gy) combined with intensified chemotherapy followed by autologous peripheral blood stem cell transplantation results in better survival in children with refractory leukemia or solid tumors. Methods Twenty-one children with malignant tumors were included in this study.There w ere 14 males and 7 females aged 3.5-12 years.Underlying disease included high -risk acute lymphoblastic leukemia (ALL, CR(1) in 3 children and CR(2) in 5 ch ildren), acute myeloblastic leukemia (AML, 9 children), non-Hodgkin’s lymphoma stage Ⅳ ( 2 children), and neuroblastoma stage Ⅳ (2 children).The peripheral hematopoi etic stem cells were collected six to eleven months after complete response, mob ilized with high dose chemotherapy alone or combined with GM-CSF or G-CSF.Th e conditioning regimen consisted of chemotherapy with two to three combinations of the following drugs: cyclophosphamide, arabinosylcytosine, McNU, etopside, an d Idarubicin on the basis ofTBI (6.0-9.0 Gy).A mean of (1.8±0.5) ×10(8)/kg autologous mononuclear cells were transplanted.The patients were followed up after transplantation. Results Severe bone marrow suppression occurred in all patients around day +7.Peripher al white blood cell count decreased to 0 in all patients at day +4.8±2.9, and platelet count decreased to less than 20×10(9)/L at day +9.0±2.6.Succ essful engraftment was achieved in 21 patients, but four died of infection at da y +17, +20, +31 and +67, respectively.Recovery of white blood cell (WBC) to 10×10(9)/L, absolute neutrophil count to 0.5×10(9)/L, platelet count to 20 ×10(9)/L occurred on 21±12, 26±13, and 27±10 days, respectively.During the follow up period, three patients relapsed at +5 months, +1.5 years, and +2 yea rs 10 months, respectively.One patient died of intracranial hemorrhage at +8 m onths.Thirteen patients had event-free survival for 2-12 years, with a mean o f 6.7±3.4 years.Conclusion Our preliminary data suggest that myeloablative therapy with low dose TBI (6.0 -9.0 Gy) combined with intensified chemotherapy followed by autologous periphe ral blood stem cell transplantation might be associated with favorable results i n children with refractory leukemia or solid tumors.