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PubMed1990

Patient acceptance of prenatal alpha-fetoprotein screening: a preliminary study.

Forty-five obstetrical patients who received an educational session about maternal serum alpha-fetoprotein (MSAFP) screening were followed until the 20th to 26th week of gestation to determine what percentage would decide to have MSAFP testing. These patients were then given a knowledge test and questioned about the factors that led to their decision about the test. Fourteen of the 45 study patients (31%) elected to have MSAFP testing. The patient's decision to have MSAFP testing was found to be significantly associated with 1) reporting a longer length of time discussing the test with the physician, 2) reporting that the opinion of a significant other about the test was important, and 3) older age. There is a need for further study of patients' acceptance of MSAFP testing to see if the relatively low acceptance rate found in this study is also found in other practices.

Chi-Square Distribution↗
PubMed1991

The effects of vitamin K on the generation of des-gamma-carboxy prothrombin (PIVKA-II) in patients with hepatocellular carcinoma.

The clinical significance of des-gamma-carboxy prothrombin (PIVKA-II) in hepatocellular carcinoma (HCC) was investigated in 112 patients with and without vitamin K administration. The positivity rate of PIVKA-II was significantly decreased in patients receiving vitamin K (28.5%), compared with those without vitamin K administration (54.5%, p less than 0.05). The plasma levels of vitamin K derivatives [phylloquinone (VK1), menaquinone-4 (MK4), and menaquinone-7 (MK7)] measured were not decreased in patients with HCC, but were significantly increased in MK4 and VK1 + MK4 + MK7. The amount of PIVKA-II in plasma did not correlate with the plasma levels of vitamin K derivatives. However, PIVKA-II was decreased by the administration of vitamin K, and all of the six patients with more than 5.0 ng/ml of VK1 + MK4 + MK7 were within normal limits, whereas half of 32 patients with less than that had abnormal levels of PIVKA-II. Thus, it was suggested that PIVKA-II was not elevated due to vitamin K deficiency, but might result from the impaired metabolism or availability of vitamin K in the tumor. Therefore, PIVKA-II should be measured without vitamin K administration.

Biomarkers↗
PubMed1991

A comparative study of the effects of nitrendipine and enalapril in essential hypertension.

In this study, we compared the effects of nitrendipine (20-40 mg daily) and enalapril (20-40 mg daily) in 44 patients with mild to moderate essential hypertension. After a 4-week placebo period, the patients entered a double-blind, crossover study of 16 weeks, divided by a second 4-week placebo period. Sitting and standing blood pressures (standard mercurymeter) were measured every 2 weeks. Ten patients dropped out, so 34 patients were evaluable. Two patients dropped out because of surgery, one patient was withdrawn because of accelerating hypertension, and seven patients discontinued because of side effects (two on placebo, four on enalapril, and one on nitrendipine). Sitting blood pressures decreased from 172 +/- 3/107 +/- 1 to 159 +/- 3/94 +/- 1 mm Hg on nitrendipine (p less than 0.001) and to 157 +/- 4/96 +/- 2 mm Hg on enalapril (p less than 0.001). The heart rate did not change. Both compounds had no significant effect on serum lipids and on renal function. With regard to side effects, flushing occurred in 10 patients on nitrendipine and in 3 on enalapril (p less than 0.05); cough was noted in 3 patients on enalapril. When using a diastolic pressure less than 95 mm Hg as a response, 72% responded on nitrendipine and 64% on enalapril (n.s.). In conclusion, nitrendipine and enalapril, given as monotherapy, were equally effective antihypertensive agents in this group of patients with uncomplicated, moderate, essential hypertension. The use of either of the tested agents seems to be more limited by its specific side effects than the lack of antihypertensive efficacy.

Blood Pressure↗
PubMed1992

Unsuspected preexisting saphenous vein disease: an unrecognized cause of vein bypass failure.

Our prior anecdotal experience with unsuspected preexisting saphenous vein disease prompted us to study its incidence, its relation to graft failure, and to identify techniques for its detection. Thick-walled, postphlebitic sclerotic occluded, postphlebitic sclerotic recanalized, calcified, and varicose vein lesions were detected in 63 (12%) of 513 infrainguinal vein bypasses. In 13 (2% to 5%) cases, severe saphenous vein disease precluded use of the vein. In the remaining 50 cases, the entire vein or a portion thereof, with minimal or unsuspected disease, was used for bypass. Early graft failures occurred in 10 (20%) of the 50 cases. The cumulative primary patency rate at 30 months for bypasses performed with diseased veins was 32%. This was significantly less than the 73% cumulative primary patency rate for bypasses with veins without detectable disease (p less than or equal to 0.001). Retrospective evaluation of preoperative duplex ultrasonography (n = 21) originally used to evaluate saphenous vein length and diameter correctly identified thick-walled, occluded, calcified, and varicose veins in 62% of cases. Intraoperative methods of vein evaluation included inspection, palpation, irrigation, catheter or valvulotome insertion to identify obstruction, and intraoperative arteriography. Histologic examination of diseased veins demonstrated a spectrum of disease with thickening of the intima and media, vein wall calcification, and luminal recanalization. We conclude that (1) unsuspected preexisting saphenous vein disease occurs in approximately 12% of cases and results in both early and late graft failures; (2) detection, in some cases, is possible with duplex ultrasonography and intraoperative techniques; and (3) diseased veins that are recanalized, calcified, or thick-walled should not be used if an alternative vein is available.

Chi-Square Distribution↗
PubMed1992

Plasma viremia in human immunodeficiency virus infection: relationship to stage of disease and antiviral treatment.

Quantitative culture of human immunodeficiency virus (HIV) was performed on 121 plasma samples from 76 HIV-infected individuals to determine the sensitivity of the assay at different stages of disease and to measure the effect of antiviral therapy on plasma viremia. Plasma virus was detected in 49 of 76 (64%) of patients, primarily those with AIDS and AIDS-related complex (36 of 38) versus asymptomatic subjects (13 of 38) (p less than 0.001, chi 2). Similarly, plasma cultures were more often positive in patients with less than 250 CD4+ T cells per microliter (38 of 40) than in those with greater than 250 CD4+ T cells per microliter (11 of 36) (p less than 0.001, chi 2). Plasma virus cultures were also more likely to be positive in patients with detectable serum p24 antigen (24 of 26) than in those without detectable p24 antigen (25 of 50) (p = 0.0023, chi 2). An effect of zidovudine (ZDV) treatment on plasma viremia was seen in a comparison of treated and untreated patients with less than 250 CD4+ T cells per microliter. Geometric mean titers of plasma viremia from 16 patients treated with ZDV for more than 3 months were significantly lower than titers from 24 untreated patients (10(1.3) versus 10(2.1), p less than 0.05, Student's t test. A comparison of pre- and posttherapy titers in 33 patients receiving antiviral treatment showed that plasma virus was not detectable at either time in 17 patients; there was a fall in plasma virus titer in 12; and titers were unchanged or increased in 4. In patients with advanced disease, plasma viremia is a potential marker of antiviral drug activity.

AIDS-Related Complex↗
PubMed1992

In-use comparison of latex gloves in two high-risk units: surgical intensive care and acquired immunodeficiency syndrome.

This study was designed to compare use patterns and leakage of gloves from two high-risk units: a surgical intensive care unit (SICU) and an acquired immunodeficiency syndrome (AIDS) unit. During a 3-month interval, the use of gloves during clinical procedures by nursing personnel was observed and recorded. A total of 2900 latex examination gloves were collected and tested in the laboratory by the watertight leakage test: 59% (1714) were from the SICU and 41% (1186) from the AIDS unit. Twenty-four percent (700) of all gloves leaked: 29% (500/1714) leaked when worn by staff in the SICU as compared with 17% (200/1186) leakage rate in the AIDS unit (chi-square = 57.32, p less than 0.05). This difference could be attributed in part to higher levels of stress to the gloves and longer wearing time in the SICU.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Comparison of cardiac morbidity between aortic and infrainguinal operations. Study of Perioperative Ischemia (SPI) Research Group.

We prospectively compared the differences in perioperative cardiac ischemic events in 140 patients undergoing major abdominal (n = 53) versus infrainguinal (n = 87) vascular operations. Preoperative dipyridamole thallium cardiac scintigraphy was performed in a subset of 38 of these patients, with treating physicians blinded to the test results. Myocardial ischemia was measured during operation with use of continuous 12-lead electrocardiography (ECG) and transesophageal echocardiography. Continuous two-lead ambulatory ECG (Holter monitoring) was performed before, during, and after operation for 4 days. Outcome events were cardiac death, nonfatal myocardial infarction, unstable angina, ventricular tachycardia, and congestive heart failure. Results of the study indicated that most demographic variables, such as age, hypertension, cigarette smoking, serum cholesterol, were comparable between patients having aortic or infrainguinal arterial operations. However, in the infrainguinal group more patients had diabetes, second vascular operations, angina pectoris, heart failure, dysrhythmias, and used digitalis. Abnormalities in preoperative Holter monitoring, ECGs, and thallium scan abnormalities were equivalent between groups. During operation, whereas Holter and ECG abnormalities were comparable, more patients undergoing aortic procedures suffered ischemia as determined by transesophageal echocardiography (26% vs 10%, p = 0.019). After operation there were 21 (24%) outcome events in patients having infrainguinal bypasses compared with 15 (28%) patients having aortic procedures (p = NS). Ischemia by Holter monitoring (n = 133) occurred after operation in 46 (57%) patients having infrainguinal operations compared with 16 (31%) patients having aortic reconstructions (p = 0.005). Because preoperative cardiac disease and adverse cardiac outcomes occurred with similar or even greater frequency in both groups of patients, we conclude that the risk for postoperative cardiac ischemic events in lower extremity vascular operations is at least as great as for aortic operations.

Aged↗
PubMed1991

Signs and symptoms of temporomandibular joint muscle pain dysfunction syndrome: a retrospective study of one hundred patients.

A retrospective serial study was carried out on one hundred randomly selected temporomandibular joint muscle pain dysfunction syndrome (TMJMPDS) patients who had attended a private prosthodontic practice over an eight year period. The study looked at common signs, symptoms and referral patterns in this group and compared them with those quoted in a large section of the literature on the subject.

Adolescent↗
PubMed1978

Log normal distribution of ovarian and placental steroid values in early human pregnancy.

Concentrations of estradiol, progesterone, 17OH-progesterone were measured by radioimmunoassay in individual serum samples obtained from a group of 304 women with normal gestations between the 4th and 17th week of pregnancy. Values obtained underwent statistical analysis in order to determine the arithmetic mean and the 95% normal range (+/- two standard deviations). It was noted hereby that the spread of values above the mean was greater than that below the mean, and that very often the mean minus two standard deviations was either close to zero or negative. Therefore, the data for each hormone were analyzed for normality of the distributions by the chi-square test. For each hormone the chi-square test was significantly different (p less than 0.001) from the normal distribution (Gaussian). Subsequently, linear transformation by rankit analysis revealed the log-normal distribution of our data. Furthermore, rankit analysis was used as a graphical method to delineate a useful clinical range, which includes the mean and meaningful 95% confidence limits for estradiol, progesterone, and 17OH-progesterone in early normal pregnancies.

Estradiol↗
PubMed1992

Pituitary adenomas: tumor cell growth by cluster formation. Pattern analysis based on immunohistochemistry.

The topographical distribution of adrenocorticotropic hormone, growth hormone and prolactin was studied in nine multihormonal pituitary adenomas and two normal adenohypophyses using quantitative immunohistochemical methods. For each pituitary hormone paraffin sections stained by antihormone antibodies were scanned with a light microscope equipped with a projection and scanning device. The number of immunoreactive cells of each square in the grid was counted and transformed into pseudocolors. In this way, the distribution of each hormone was documented. A chi-square test was applied to these distribution patterns to prove randomness. A nonrandom distribution of immunoreactive cells was observed in all pituitary adenomas and normal pituitary glands. Cluster formations of immunoreactive cells were found for each hormone. The clusters were surrounded by halo-like areas of decreasing number of immunoreactive cells from center to periphery. The cluster-halo type of immunoreactive cells was found not only in the adenomas but also in the normal pituitary gland. This may be explained by the similarity of biological processes during cell proliferation either in normal development or in adenoma formation. It can be concluded from our studies that pituitary adenomas in most cases develop by multicentric but not diffuse proliferation of cell clones of different endocrine activity.

Adenoma↗
PubMed1992

Anti-toxoplasma serotitres in uveitis and ocular toxoplasmosis.

This study was based on anti-toxoplasma serotitres obtained from 80 normal healthy adults and 103 consecutive patients with anterior, posterior and panuveitis over a 42 month period. Twelve out of 80 (15%) normal healthy sera were found to have low titres (1:64 to 1:256), while 3 (3.8%) had high titres (1:1024 or higher). The distribution of serotitres in patients with clinical toxoplasmosis was significantly different from the population sample (p less than 0.001, chi-squared test). Similarly, the distribution of serotitres in patients with posterior uveitis (of which 28 out of 54 were clinically ocular toxoplasmosis) having serotitres of 1:1024 or greater, was found to be significantly different from the normal population (p less than 0.001, Chi-squared test), but not statistically different from those with clinical ocular toxoplasmosis. Hence, anti-toxoplasma serotitre is useful as a diagnostic screening tool only in patients with posterior uveitis. It is also useful in confirming cases of suspected clinically positive ocular toxoplasmosis in our local population.

Adolescent↗
PubMed2026

A profile of suspected female homicide cases at the Johannesburg and Diepkloof Forensic Pathology Service Medico-legal Mortuaries for 2020-2022.

This study profiles suspected female homicide victims in Johannesburg, South Africa, during the COVID-19 period marked by socio-environmental changes from lockdown restrictions. Guided by the Socio-Ecological Model, a retrospective case series of 369 victims was reviewed using medico-legal mortuary records from Johannesburg and Diepkloof Forensic Pathology Service facilities. Descriptive analyses were conducted, supplemented by a chi-square test to assess whether distributions of causes of death among women differed between COVID-19 and non-COVID-19 periods. No statistically significant association was found, χ2 (6, N = 339) = 6.68, p = 0.35. Key findings highlight that Black, unemployed, unmarried women aged 21-40 were at greatest risk. Cause of death was established in 97.0% (358/369) of cases, with firearm injuries predominating (43.9%), followed by sharp‑force (24.5%) and blunt‑force trauma (13.1%). Approximately 90% of victims were suspected to have been killed by males, with half of deaths attributed to intimate partner violence. Homicide frequency decreased during strict lockdowns but rose as restrictions eased, suggesting that movement and alcohol controls may reduce risk. Despite temporary disturbance caused by COVID‑19 restrictions, the underlying risk profile of female homicide victims remained unchanged. These findings inform multi-level prevention and intervention strategies in South Africa.

Humans↗
PubMed2026

PIK3CA Polymorphisms in Cervical Cancer: Differential Impact of rs6443624 and rs141178472.

BACKGROUND: Cervical cancer remains a major cause of mortality in low- and middle-income settings. We assessed whether two PIK3CA single-nucleotide polymorphisms (SNPs) rs6443624 (A/C) and rs141178472 (C/T) are associated with disease risk, clinicopathological features, and survival. MATERIALS AND METHODS: In a prospective case control study at a tertiary center, 154 participants were enrolled (77 cases, 77 controls). Genomic DNA was isolated from FFPE cervical tumors (QIAamp DNA FFPE Tissue Kit) and genotyped using TaqMan allelic discrimination. Clinicopathological variables (FIGO stage, histology, grade, treatment, tumor-infiltrating lymphocytes [TILs]) were abstracted from records. Genotype distributions were compared by Pearson chi-square. Associations with clinicopathological features used chi-square/Fisher's exact as appropriate; ANOVA compared age across genotypes. Overall survival (OS) was estimated by Kaplan-Meier and compared with the log-rank test; mean OS with SE and 95% CI is reported. RESULTS: Cases were predominantly locally advanced at presentation and squamous histology; most were moderately differentiated. rs6443624 differed significantly between cases and controls (&#x3c7;&#xb2;=21.1, p<0.001), with CC over-represented in cases and CA less frequent. rs141178472 showed no significant case control difference (&#x3c7;&#xb2;=2.9, p=0.086). For OS, rs6443624 showed a significant genotype effect (log-rank &#x3c7;&#xb2;=23.45, p=0.001): AA had the poorest survival, CA the longest, CC intermediate. rs141178472 was not associated with OS (&#x3c7;&#xb2;=1.06, p=0.588). Genotype clinicopathological correlations for stage group, grade, TILs, and treatment were non-significant or inconsistent, with some comparisons limited by small sample sizes. CONCLUSION: The PIK3CA rs6443624 variant appears to influence both susceptibility and prognosis in cervical cancer, highlighting its potential as a biomarker for molecular risk stratification. Validation in larger, multi-center cohorts incorporating HPV/p16 assessment and extended follow-up is warranted to confirm its clinical relevance.

Humans↗
PubMed1992

[A study on effects of parents age, birth order and mental retardation of unknown etiology].

On this report 461 matched cases of mental retardation of unknown aetiology were analysed on the relationship between the diseases and the parents age, birth orders with conditional Logistic regression. These cases were accurately diagnosed and selected from the Epidemiologic Survey of genetic diseases of Sichuan, China. The results found that mental retardation of unknown aetiology is related to the age of parents and birth order. The paternal age is the main factor while the maternal age in not a significant effect and birth order also in not a significant effect after readjusting the other factors. Compared to paternal age group of under 25. There are significant increase of relative risks of age group 30-34 and 45 above, about 1.8 and 2.7 fold increase in univariate analysis and 1.9 and 3.3 fold increase in controlling the maternal age and birth order, a chi-square test for trend of distribution of paternal age also indicates a significant dose response relationship between increasing risk with age. The significance of result and methods of analysis were discussed.

Adult↗
PubMed1992

[Nursing needs of the elderly in hospital from the nurses' viewpoint].

The human needs of elderly people in hospital were studied from the point of view of the nursing staff in order to describe how important nurses perceive the satisfaction of these needs to be, what kinds of needs they regard as significant or insignificant and what opportunities they have to influence their satisfaction. The data were collected using questionnaires, filled in by 130 nurses working in 14 geriatric wards in the hospital attached to a Health Centre. Human needs were evaluated on a scale based on the theory of human needs created by Yura and Walsh. The data were analysed by quantitative statistical methods: frequency and percentage distributions, cross tabulations and the Chi-Square test. The nurses regarded the satisfaction of human needs among the elderly as extremely or very important in most of the answers (70%) and as important in 27%. In only 3% did the nurses describe this aspect as being of little importance or insignificant. The satisfaction of many psychosociological and physiological needs was also regarded as extremely or very important. Nearly half of the nurses (49%) described the satisfaction of sexuality needs as important, a quarter (25%) as extremely or very important, and the remaining quarter (25%) regarded these needs as of little importance or insignificant.

Aged↗
PubMed1992

Factors influencing resident career choices in emergency medicine.

OBJECTIVE: To assess the attitudes of residents in emergency medicine regarding a career in academics. DESIGN: A 22-item questionnaire was administered to residents in conjunction with the yearly American Board of Emergency Medicine inservice examination. Demographic information and factors influencing career intent were elicited. Respondents were classified by intent on a career in emergency medicine. A three-way analysis of variance was used to address group differences for eight specific factors impacting on career decision. Chi-square analysis was used to address questions involving relationships among variables with dichotomous or categorical responses. RESULTS: The survey was distributed to 1,654 residents, and 1,238 (75%) completed the questionnaire. Motivating factors demonstrating significant differences between those residents planning an academic career and those not interested in academe were a desire to do research, desire to teach, desire to make a contribution to medicine, and exposure to role models, with less emphasis on the need for free time for other interests and less concern regarding practice location. More than 80% of those not going into academic emergency medicine believed they were adequately exposed to research in residency compared with 65% of those intent on a career in academe (P less than .01). Research in medical school, residency, and authorship of a research paper were significantly more prevalent for those residents desiring a career in academe (P less than .01). Twenty-six percent of residents responded that their role models for research were less than adequate. Seventeen percent of residents intend to take fellowship training. The most popular fields for fellowships were toxicology (25%), emergency medical services (21%), pediatrics (15%), and research (9%). CONCLUSION: The results of this survey address attitudes among residents toward a career in academic emergency medicine. Factors such as motivation, role models, and exposure to research may help academicians plan strategies to meet the future needs of academic emergency medicine.

Attitude of Health Personnel↗
PubMed1976

The distribution of fetal death in control mice and its implications on statistical tests for dominant lethal effects.

In dominant lethal testing fetal death is generally assumed to follow either a Poisson or binomial distribution. However, both of these models were found to be inappropriate when three large sets of mouse control data and other data sets from the literature were examined. The validity of statistical test procedures based on these inappropriate models was then studied in detail. It was found that chi-square tests (which assume an underlying binomial distribution) may seriously exaggerate the level of significance and hence should not be used. In contrast, the inappropriateness of the underlying Poisson or binomial model appeared to have little effect on the validity of pairwise comparisons by analysis of variance procedures. Unlike chi-square, these procedures regard the pregnant female rather than the individual implant as the experimental unit. However, a statistical analysis of dominant lethal data generally involves more than a series of pairwise comparisons, and it is unclear how an invalid underlying model may affect statistical test procedures in this more complex situation. Moreover, it is difficult to justify the use of statistical models that are demonstrably invalid when a reasonable alternative exists. Thus, until a satisfactory parametric model can be found and appropriate test procedures derived, we prefer to analyze dominant lethal data by non-parametric (distribution-free) methods. Proportion of dead implants per female appears to be a more meaningful measure of fetal death than number of dead implants per female for several seasons which include (1) analyses based on proportions take the total number of implants per female into account and (2) analyses based on proportions make more reasonable assumptions concerning pre-implantation losses and are more powerful when such losses occur. Despite our concern with the appropriateness of the underlying model, in practice we have found few instances in which non-parametric and analysis of variance procedures have led to markedly different conclusions.

Animals↗