Life Change Events,Ballistocardiography and Coronary Death

Abstract

Thirty-six men and women who experienced a documented myocardial infarction, half of whom ultimately died from their disease and half of whom survived over a six-year period, provided longitudinal recent life changes and ballistocardiographic data. The 18 patients who died from their coronary disease indicated a significant buildup in life changes which peaked approximately one year prior to death; their serial ballistocardiograms indicated a significant buildup in average force of contraction which was seen to peak approximately six months prior to death. The 18 post-infarction patients who survived the six-year follow-up showed neither a buildup in life change nor a buildup in the ballistocardiographic index of cardiac contraction force. These findings of a life change peak preceding ballistocardiographic evidence of an “overworked” heart are discussed in terms of their possible medical and psychophysiological significances.     

Identification and characterization of aquaporin-2 water channel mutations causing nephrogenic diabetes insipidus with partial vasopressin response

Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused most often by mutations in the vasopressin V2 receptor (AVPR2). We studied a family which included a female patient with NDI with symptoms dating from infancy. The patient responded to large doses of desmopressin (dDAVP) which decreased urine volume from 10 to 4 I/day. Neither the parents nor the three sisters were polyuric. The patient was found to be a compound heterozygote for two novel recessive point mutations in the aquaporin-2 (AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is the site for inhibition of water permeation by mercurial compounds and is located near to the NPA motif conserved in all aquaporins. Osmotic water permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2 was not increased over water control, while expression of L22V cRNA increased the Pf to approximately 60% of that for wild-type AQP2. Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO cells showed that the C181W mutant had an endoplasmic reticulum-like intracellular distribution, whereas L22V and wild-type AQP2 showed endosome and plasma membrane staining. Water permeability assays showed a high Pf in cells expressing wild-type and L22V AQP2. This study indicates that AQP2 mutations can confer partially responsive NDI.      

The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission

Factors involved in the stability of trinucleotide repeats during transmission were studied in 139 families in which a full mutation, premutation or intermediate allele at either FRAXA or FRAXE was segregating. The transmission of alleles at FRAXA, FRAXE and four microsatellite loci were recorded for all individuals. Instability within the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for FRAXE) was extremely rare; only one example was observed, an increased in size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were unstably transmitted. Instability was more frequent for FRAXA intermediate alleles that had a tract of pure CGG greater than 37 although instability only occurred in two of 13 such transmissions: the changes observed were limited to only one or two repeats. Premutation FRAXA alleles over 100 repeats expanded to a full mutation during female transmission in 100% of cases, in agreement with other published series. There was no clear correlation between haplotype and probability of expansion of FRAXA premutations. Instability at FRAXA or FRAXE was more often observed in conjunction with a second instability at an independent locus suggesting genomic instability as a possible mechanism by which at least some FRAXA and FRAXE mutations arise.      

Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx?

A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.      

Impact of echocardiography on the management of patients with mitral valve prolapse

OBJECTIVE: To determine whether echocardiography affects the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients suspected of having mitral valve prolapse (MVP). DESIGN: Retrospective review of echocardiograms and clinical records. SETTING: Military tertiary care hospital. PATIENTS: 127 patients with clinically suspected MVP (105) or incidentally discovered MVP (22). MAIN RESULTS: Beta blockers were used more often in patients with suspected MVP and positive echocardiograms (45%) than in patients with normal echocardiograms (13%, p less than 0.001). Bacterial endocarditis prophylaxis was recommended more often in patients with suspected MVP and positive echocardiograms (65%) than in patients with normal echocardiograms (11%, p less than 0.001). Presence or absence of a murmur did not influence the decision to recommend bacterial endocarditis prophylaxis. Patients in whom MVP was incidentally discovered were unlikely to receive either beta blockers or the recommendation for bacterial endocarditis prophylaxis. CONCLUSIONS: The results of echocardiography affect the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients with suspected MVP.     

Life-threatening complications associated with acute monocytic leukaemia after dental treatment

It is highly recommended to conduct a prophylactic check for any dental problems on patients who suffer from leukaemia before chemotherapy begins. Bacteraemia caused by oral microflora may be very dangerous for patients with haematological malignancies. However, it should be noted that the prophylactic process itself might bring about life-threatening complications if there is only a short interval between dental treatment and the beginning of chemotherapy, or if the dental treatment is too aggressive. We present a case where this prophylactic procedure produced life-threatening complications for a patient with acute myeloid leukaemia.     

Platelet activation status decreases after menopause

Objective.?The aim of the study was to investigate the impact of the climacterium (before and after menopause) on platelet activation.

Background.?Platelet activation has been associated to the risk of cardiovascular disease. There is much speculation about the relationship between platelet function and sex steroids, due to peculiarities of platelet action between the genders, including concerns about the influence of low estradiol status in menopausal women.

Methods.?By means of a cross-sectional study design, 37 female patients divided into two groups were compared. Group A consisted of ten women, mean age 43.9 years, in the premenopausal period, with normal estrogen levels; and Group B comprised 27 patients, mean age 53.0 years, who had all reached menopause. Platelet activation markers, namely P-selectin and glycoprotein IIb–IIIa complex (GPIIb–IIIa), were evaluated by flow cytometry with monoclonal antibodies. A binding index was calculated for both parameters (percentage of positive platelets?×?mean fluorescence of positive platelets). Also, thromboxane A₂ was quantified by means of its main plasma metabolite, thromboxane B₂, by enzyme immunoassay.

Results.?P-selectin and GPIIb–IIIa expression results revealed lower platelet activation status after menopause, as there was a decrease in both the percentage of P-selectin^?+? platelets and of GPIIb–IIIa mean fluorescence of positive platelets, lowering both binding indices. P-selectin binding index differed significantly between Group A (12.3?±?3, n?=?10) and Group B (6.2?±?2.9, n?=?27; mean?±?standard deviation (SD), p?<?0.001). GPIIb–IIIa binding index also differed significantly between both groups (Group A: 18.8?±?2.3, n?=?10 vs. Group B: 16.2?±?3.1, n?=?27; mean?±?SD, p?<?0.0018). Plasma concentration of thromboxane B₂ was 1.07?±?0.5?pg/well before menopause (Group A, n?=?10) and 1.9?±?4.1?pg/well after menopause (Group B, n?=?27), not significantly different (mean?±?SD, baseline?×?therapy, p?=?0.85).

Conclusions.?After the menopause, climacteric women – whose estradiol status is low – have a decreased activation platelet status compared with premenopausal women. Nevertheless, further studies on a larger sample are necessary for conclusive data regarding cardiovascular disease.