Automatic measurement of blood pressure: evaluation of the Copal UA-231 automatic sphygmomanometer

The suitability of an automatic sphygmomanometer for epidemiological work was evaluated in two studies. In the first, blood pressure measurements were made alternately on the automatic machine and on a Hawksley random zero instrument on 14 volunteers on each of four consecutive days by a single medical observer. No significant difference was found between the mean diastolic pressure obtained by each instrument but the mean systolic pressure was 5 mm higher on average on the automatic machine. In the second study, the effect of cuff position for the automatic instrument was examined. Differences between recommended and errant cuff positions of up to 4.5 mmHg were recorded but these did not reach statistical significance. These studies indicate that if used carefully this automatic instrument is suitable for survey and experimental use.

Expulsions in immediate postpartum insertions of Lippes Loop D and Copper T IUDs and their counterpart Delta devices--an epidemiological analysis

In this paper, an epidemiological analysis was performed, using an international data set, exclusively on the expulsion problem associated with postpartum IUD insertions. The inserter's experience in postplacental insertions is probably an important determining factor for IUD expulsions. Immediate insertions (within 10 minutes after placental delivery) are possibly associated with lower expulsion rates than later insertions (eg. two to 72 hours after placental delivery) during the woman's postpartum hospitalization. No significant differences were detected between the standard Lippes Loop D and Copper T IUDs and their counterpart Delta devices specifically designed for postpartum use, between the two types of Delta device or between the hand and inserter methods. A case-control analysis also did not detect any significant association between IUD expulsions and mild complications occurring or management performed during the third stage of labor and delivery. The practical implications of these findings, the methodologic problems of this analysis and future research strategies are also discussed.

Phorbol esters inhibit gluconeogenesis in canine renal proximal tubular segments

Gluconeogenesis is a major metabolic function of the renal proximal tubular cell. To characterize the regulation of this process in proximal tubule, glucose production from gluconeogenic precursors was measured in proximal tubular segments prepared from dog kidney. Production of glucose was a linear function of time for up to 120 min of incubation at 37 degrees C under a variety of conditions. Lowering the pH of incubation media from 7.5 to 7.0 increased glucose synthesis. Production of glucose was inhibited by 3-mercaptopicolinate. Incubation of proximal tubular segments with insulin diminished synthesis of glucose. Incubation of segments with tumor-promoting phorbol esters, 12-O-tetradecanoylphorbol-13-acetate or phorbol 12,13-dibutyrate, resulted in decreased production of glucose. This effect was not observed following incubation with the inactive phorbol ester 4 alpha-phorbol. Changes in glucose synthesis could not be attributed to alterations in cell viability or in rates of glucose oxidation induced by experimental maneuvers. Our findings confirm the usefulness of proximal tubular segments for characterization of metabolic processes in this portion of the nephron. The experimental results are consistent with a role for protein kinase C in the control of gluconeogenesis in proximal tubule.

Residual insulin secretion in insulin dependent diabetes mellitus

The residual insulin secretory capacity of 244 children with insulin dependent diabetes mellitus was determined by measurement of their 24 hour urinary C peptide excretion. An inverse linear relation was found between the residual B cell secretion and the duration of diabetes. The age at onset of diabetes did not affect the residual B cell function significantly.

Grip and pinch strength: normative data for adults

The primary purpose of this study was to establish clinical norms for adults aged 20 to 75+ years on four tests of hand strength. A dynamometer was used to measure grip strength and a pinch gauge to measure tip, key, and palmar pinch. A sample of 310 male and 328 female adults, ages 20 to 94, from the seven-county Milwaukee area were tested using standardized positioning and instructions. Right hand and left hand data were stratified into 12 age groups for both sexes. This stratification provides a means of comparing the score of individual patients to that of normal subjects of the same age and sex. The highest grip strength scores occurred in the 25 to 39 age groups. For tip, key, and palmar pinch the average scores were relatively stable from 20 to 59 years, with a gradual decline from 60 to 79 years. A high correlation was seen between grip strength and age, but a low to moderate correlation between pinch strength and age. The newer pinch gauge used in this study appears to read higher than that used in a previous normative study. Comparison of the average hand strength of right-handed and left-handed subjects showed only minimal differences.

Colorimetric measurement of glycosylated protein in whole blood, red blood cells, plasma and dried blood

A colorimetric method for the measurement of whole-blood glycosylation (WBG), glycosylated haemoglobin in red blood cells (GHb), glycosylated plasma protein (GPP) and dried-blood glycosylation (DBG) is described which is rapid, inexpensive and precise. GHb correlated well with HbA1 measured by cation-exchange chromatography and was also correlated with WBG, DBG and GPP. DBG, which showed good correlation with GHb, could be measured on several drops of blood dried on filter paper treated with glucose oxidase. Filter papers are posted to the laboratory prior to clinic visits, and by having the DBG result available more rational diabetic management is possible. For DBG, the intra- and inter-assay coefficient of variation at three levels is less than 6%. Reference values in non-diabetic children have been calculated and are compared with values obtained in 'good' clinical diabetic control and in 'fair' control. The filter-paper assay DBG method has a high degree of patient acceptance.

UV-mutagenesis at a cloned target sequence: converted suppressor mutation is insensitive to mutation frequency decline regardless of the gene orientation

Premutational lesions produced by ultraviolet radiation in the Gln2 tRNA genes of E. coli B/r show differing sensitivities to a mutation avoidance phenomenon known as mutation frequency decline (MFD). A mutation event that changes the wild-type gene to an amber (UAG) suppressor is normally sensitive to MFD. Mutation of this amber suppressor to an ochre (UAA) suppressor is not sensitive to MFD. These two mutation events occur in the same anticodon region of the DNA. The dissimilarity of MFD sensitivity between these two mutations may result because the respective premutational photoproducts for the two are located in opposite strands of duplex DNA. To examine the effect of strand position of the premutational lesions on MFD, recombinant lambda phage were constructed that contained the amber suppressor as a mutation target in the two possible orientations. Comparison of MFD in bacterial lysogens containing either of the two types of recombinant prophage indicated that reversing the orientation of the target sequence relative to adjacent bacterial DNA had no effect on MFD. Since rotational inversion of the target sequence did not alter the sensitivity to MFD of mutation occurring at the cloned target gene, the antimutation process inherent to MFD can not be attributed to an asymmetrical interaction between the template strands and the DNA-replication complex.

Insulin stimulates Pi transport in brush border vesicles from proximal tubular segments

Induction of hyperinsulinemia in dogs results in enhanced reabsorption of Pi from glomerular filtrate in the renal proximal tubule. To determine whether this may be a direct action of insulin mediated by altered transport characteristics of the proximal tubular brush border membrane, we measured Na+-dependent 32Pi transport in brush border membrane vesicles prepared from isolated proximal tubular segments originating from dog kidney that had been incubated with or without insulin. Specific high affinity binding sites for insulin were detected in proximal tubular segments. Increased initial rates (15 s) of Na+-dependent 32Pi transport were measured in brush border vesicles prepared from segments that had been incubated with insulin. This effect of insulin was concentration dependent over the range of 10(-10) to 10(-6) M insulin. These studies demonstrate the feasibility of using brush border vesicles prepared from proximal tubular segments to study solute transport. Our findings suggest that insulin-induced increased Pi reabsorption in the proximal tubule is mediated by a direct action of insulin on the proximal tubular cell, which results in increased Na+-Pi cotransport across the brush border membrane.

Enhanced galactose metabolism in isolated perfused livers of folate-treated suckling rats

Folic acid (1 mg/day) was administered intraperitoneally to seven-day-old suckling rats for a period of seven days. Livers of folate-treated animals took up galactose rapidly during the first 35 minutes of perfusion, whereas uptake was delayed in the controls (sham-injected and untreated). More glucose was released by all groups when galactose was perfused than when other substrates were used. With each hexose tested, livers of the folate group consistently released less glucose but more lactate than the controls. The specific activity of galactose-1-phosphate uridyltransferase was elevated in livers of the folate group compared to the controls perfused with either galactose or glucose. A similar finding was made for ATP levels in perfused livers of this group. The differences in transferase and ATP levels in perfused livers of folate-treated over the control groups may explain the enhanced galactose uptake pattern.

Comparison of Cultureset and primary rabbit kidney cell culture for the detection of herpes simplex virus

Herpes simplex virus isolation by conventional cell culture in primary rabbit kidney cells (RK) was compared with Cultureset (CS). At 24 h CS was more sensitive (31 versus 25 of 55 isolates detected) than RK, but at 48 h there was little difference (43 detected by CS, 46 by RK). CS stained at 48 h was significantly less sensitive (78.2%) than RK observed for 1 week. CS stained at 24 or 48 h was not an acceptable substitute for RK observed for 1 week.

IUD-associated hospitalization in less developed countries

Data on 11,977 insertions of an intrauterine device (IUD) from 25 collaborating centers in 16 less developed countries (LDCs) were investigated for IUD-associated hospitalizations. These centers maintained regular follow-up and reported at least one hospitalization among their IUD cases. The Lippes Loop, Copper T, Delta Loop, and Delta T were the most commonly used devices, and three-fourths of all devices were inserted in postpartum women. Fifty-five of the 128 reported subsequent hospitalizations were associated with IUD use. Main indications for IUD-associated hospitalizations were pelvic infection, bleeding/pain, and method failure. Statistically significant differences were not detected in the three-month gross cumulative rates for hospitalizations due to IUD complications by age (less than 30 vs 30+), parity (0-1 vs 2+), or device type (Lippes Loop and Copper T vs Delta devices vs others). Three types of IUD-associated hospitalization rates were calculated, each involving a margin of error: 1) a Pearl rate of 8.0 per 1,000 woman-years of IUD use; 2) a one-year life table rate of 6.3 per 1,000 insertions; and 3) crude rates ranging from 3.2 to 4.6 per 1,000 cases.

Factors regulating the specific activity of galactose-1-phosphate uridyltransferase during perfusion of suckling rat liver

The regulation of the specific activity of galactose-1-phosphate uridyltransferase (E.C.2.7.7.12) has been studied using the hexose-perfused suckling rat liver as a model. Perfusion in the recirculating mode with galactose concentrations up to 4mM resulted in enzyme activity which fluctuated significantly during a 90-min experimental period. A concentration of 10 mM galactose stabilized the enzyme activity at levels found in unperfused liver. The same stabilizing effect was seen with 10 mM glucose. The elevated transferase specific activity observed after 30 min recirculating perfusion was not seen when the nonrecirculation mode was employed suggesting a factor in the recirculating medium may mediate this effect.

Accumulation of galactonate in liver of suckling rats perfused with galactose

Livers of 14-day-old suckling rats were perfused for 30 min in the nonrecirculating (once-through) mode with media containing 0-60 mM galactose. Galactonate was detected in livers perfused with as little as 1 mM galactose and increased with higher perfusate galactose to 178 nmoles per gram of liver at 60 mM hexose. Tissue galactonate levels were as high as 60% of galactose-1-phosphate which also accumulated under the same conditions. Galactonate was also found to be present in the effluent perfusate. The perfused suckling rat liver appears to be a physiological model for assessing the role of galactose oxidation to galactonate as an alternate metabolic pathway of galactose metabolism.

Galactose metabolism in suckling and adult isolated rat hepatocytes

The metabolism of galactose during the postnatal developmental period has been examined in isolated parenchymal cells of livers from fasted rats aged 7, 14, 21, 28, and 42 days, by measuring the disappearance of 1 and 4 mM 1-[14C]galactose from the incubation media as well as [14C]galactose conversion to [14C]glucose and [14C]lactate and oxidation to [14CO2]. Cells from 7- and 14-day-old suckling animals consistently utilized galactose more rapidly (4 times greater) than those of adult. Hepatocytes of suckling rats also converted greater amounts of galactose to glucose and oxidized galactose 2-3 times faster than the adult. The conversion to glucose by suckling cells occurred with minor recycling of labeled C-1 galactose to C-6 of glucose. A comparison with [1-14C]glucose as substrate showed that oxidative rates by the young cells were 3 times faster for galactose than for glucose. This was not due to the presence of a direct galactose oxidative pathway as assessed by the [14CO2] yield from C-1 and C-2 labeled galactose. Incubation of hepatocytes with galactose appeared to augment the production of glucose from endogenous precursors, 33 nmoles/mg cells in 30 min. The enhanced glucose output from endogenous sources in isolated suckling hepatocytes incubated with galactose contrasts with the sugar's suppression of glucose output observed in isolated perfused liver even though galactose metabolism in both preparations are similarly greater in the suckling than in the adult.

Failure to insert an intrauterine device

Numerous studies have reported IUD-related events in evaluating the rates of pregnancy, expulsion, and removal for bleeding and pain, but the inability to successfully insert an IUD has been overlooked. This study analyzed data on 51 unsuccessful insertions from 22 international centers collected on standard forms. The incidence of insertion failures was estimated to be between 2.3 and 8.3/1000 attempted insertions. No statistically significant risk factors in patient characteristics were delineated through a case-control analysis. The incidence of insertion failures among postpartum cases was highest for the Delta Loop (16.8/1000 insertions). Data suggest that failure to successfully insert an IUD may not be directly attributable to any specific host characteristic but rather is contingent on agent (IUD type) and provider (inserter) factors.

Genome intermixing and sister chromatid exchange in newly-formed HeLa-3T3 Hybrid cells

Mouse and human genomes occupy distinct regions within hybrid interphase nuclei following division of HeLa-3T3 heterokaryons. With subsequent cell division the proportion of interphase cells displaying separation of human and mouse genomes decreases. Examination of several hundred hybrid colonies revealed a linear relation between the log of the fraction of interphase cells with separated genomes and the log of clone size. This indicates that there is a constant probability that separated genomes will intermingle at each mitosis. Human and mouse chromosomes can also occupy distinct sectors in metaphase spreads derived from heterokaryons. Computer analysis of the distribution of chromosomes within 548 hybrid metaphases showed that mouse and human chromosomes are randomly intermixed within several divisions and before the onset of rapid chromosome loss. Sister chromatid exchange (SCE) rates were also measured in mass populations of newly-formed HeLa-3T3 hybrid cells. For most hybrid metaphases there was not significant change in SCE rates within the human chromosome set. In a small minority of hybrid metaphases, characterized by asynchronous condensation of chromosome sets, there was a 50-fold increase in SCE. However, chromosomes are progressively lost from all hybrid cells. Thus, the two processes examined in the present studies, the distribution of human chromosomes at metaphase and SCE, are not implicated in the preferential loss of human chromosomes from HeLa-3T3 cells.

A trial of daily vitamin supplementation as a means of reducing oral contraceptive side effects and discontinuation in Sri Lanka

A 4-cell randomized, blind clinical trial was conducted at three sites in Sri Lanka to evaluate the impact of daily vitamin supplements in preventing oral contraceptive side effects and in improving continuation. No significant effects were found.

A comparison of Norinyl and Brevicon in three sites in Sri Lanka

A set of 3 four-cell randomized, blind clinical trials was carried out in Sri Lanka to evaluate the impact of vitamin supplements and different oral contraceptive formulations. This paper concentrates on the comparisons of oral contraceptives. There seems to be no important difference between Norinyl, a standard-dose oral contraceptive, and Brevicon of a lower estrogen dosage--in either continuation or side effects. Continuation at one site was higher among Norinyl users, but several factors led us to the belief that this difference was due to differences in field worker performance rather than to the pharmacological properties of the drugs. Some differences in side effects were observable along predictable lines; breakthrough bleeding was more common among Brevicon users than Norinyl users, and most other side effects were more frequent among Norinyl users, although these latter differences were quite small, and there were several exceptions.