Factors associated with rectal injury in spontaneous deliveries

Rectal injury during childbirth is a complication with potentially debilitating long-term consequences. Several factors have been suggested as influencing the risk of rectal injury. Among these are parity, infant birth weight, and various procedures performed by the birth attendant, including episiotomy. Whether episiotomies protect against or provoke laceration of the rectal sphincter and rectal mucosa is particularly controversial. Logistic analysis was used in an observational study of 2706 spontaneous cephalic deliveries to determine the risk of rectal injury for each of six explanatory factors, simultaneously controlling for the other factors. The adjusted risk for rectal injury was significantly increased for midline episiotomy (8.9 versus no episiotomy), nulliparity (3.3 versus parous), delivery by a physician (2.4 versus midwife), fetal macrosomia (2.4 versus normal weight), and delivery in a delivery room (2.0 versus labor bed). Compared with the risk for whites, significantly increased risk was found for Hispanic (1.9), Filipino (3.7), and Chinese (2.9) women. The practice of prophylactic midline episiotomy is questioned, and suggestions are offered for the design of experimental studies to resolve the questions raised.

Prophylaxis in caesarean section with cefmetazole and cefoxitin

A prospective, randomized, open comparison of three 1 g doses of cefmetazole with three 2 g doses of cefoxitin for non-elective Caesarean section was performed. Sixty-nine patients were evaluated. The two groups were comparable with respect to labour characteristics that might influence risk of postoperative infectious morbidity. Similarly, the nature of the bacterial contamination/infection of the amniotic fluid at the time of Caesarean section was comparable in the two groups. The only infectious morbidity noted was endomyometritis. The incidence was the same in both groups, 5/50 (10%) in the cefmetazole group and 2/19 (10.5%) in the cefoxitin group. Febrile morbidity, as reflected in the fever index, was not significantly different between the groups, 10.2 +/- 18.5 degree hours in the cefmetazole group and 7.5 +/- 11.7 degree hours in the cefoxitin group. Cefmetazole appeared to be equivalent to cefoxitin in reducing post-Caesarean section endomyometritis.

Use of ranitidine in children undergoing cardiopulmonary bypass

Sixty children aged 6 wk to 10 yr were studied. The children were undergoing cardiopulmonary bypass (CPB) for correction of congenital heart defects. The aim of the study was to provide prophylaxis for stress-induced gastric ulceration by elevating the gastric pH to at least 3.5. Two infusion regimes of ranitidine were compared: 0.1 and 0.2 mg/kg.h. The period of study was from induction of anesthesia until the end of the first 24 h after surgery. Both regimes were effective. The 0.2-mg/kg.h infusion produced a significantly higher plasma concentration of ranitidine throughout the study period without any additional clinical benefit. Both regimes produced, within 3 h of cessation of CPB, a significant elevation in mean gastric pH to at least 5.3. This paper concludes that 0.1-mg/kg.h infusion of ranitidine is a safe and efficacious regime for the critically ill pediatric patient.

Experimental uraemia with associated plasma amino acid abnormalities but without retarded food intake and weight gain

A rat model of moderate uraemia is described in which uraemic animals attain normal food intake and weight gain. Despite the low levels of the induced uraemia, which has been well defined, changes in plasma amino acid concentrations associated with experimental uraemia still occur. It appears from this study that a reduction in food intake is not a major factor in the aetiology of the plasma amino acid changes seen in uraemia and that the model may prove useful in future studies of experimental chronic renal failure.

Monoclonal antibodies to sperm surface antigens of the brown alga Fucus serratus exhibit region-, gamete-, species- and genus-preferential binding

A panel of twelve monoclonal antibodies (MAbs), designated FS1 to FS12, have been raised against surface antigens of Fucus serratus sperm. The antibodies were selected on the basis that they show region-, gamete-, species- or genus-preferential binding. Indirect immunofluorescence shows that the antigens bound by the MAbs are distributed non-randomly over the cell surface. Seven MAbs (FS1, FS3, FS4, FS6, FS8, FS9, FS10) bind antigens located primarily on the cell body, while the others (FS2, FS5, FS7, FS11, FS12) bind antigens located primarily on the anterior flagellum. Of the MAbs that label the anterior flagellum, FS2, FS5, FS7 and FS12 form a 'halo' at the perimeter of the flagellum. Electron microscopic-immunogold studies indicate that the 'halo' results from labelling of the mastigonemes, as opposed to the flagellar plasmamembrane. Gamete-preferential binding of antibodies was detected using an enzyme-linked immunosorbent assay with egg membrane vesicles. Eight of the MAbs bind sperm antigens not common to eggs, though FS2, FS4, FS5 and FS9 bind antigens present on both sperm and eggs. In studies of species- and genus-specificity FS2, FS3, FS5, FS6, FS7, FS8, FS10, FS11 and FS12 exhibit genus-preferential binding, labelling sperm of F. serratus and F. vesiculosus more intensely than that of Ascophyllum nodosum. Only FS10 showed marked species-preferential binding, labelling sperm of F. serratus much more intensely than that of F. vesiculosus.

Skeletal blood flow, iliac histomorphometry, and strontium kinetics in osteoporosis: a relationship between blood flow and corrected apposition rate

In 20 untreated patients with idiopathic or postmenopausal osteoporosis, kinetic studies of skeletal blood flow (using 18F) and bone turnover (using 85Sr) were combined with dynamic histomorphometry performed on transiliac biopsies taken within 6 weeks of each other. In 8 patients the combined studies were repeated after treatment. A further 5 patients were studied only while receiving treatment. As expected, skeletal blood flow measured by 18F correlated with an index of 85Sr uptake into the exchangeable pools of bone. Additionally and independently, skeletal blood flow correlated with an index of the work rate of the osteoblasts in each multicellular unit of bone (the corrected apposition rate of Parfitt). These correlations were statistically significant in both the untreated patients (P less than 0.05) and the whole group (P less than 0.001). Further indices related to bone turnover at the level of the skeleton as a whole were significantly associated with skeletal blood flow only in the combined group.

An outbreak of lymphosarcoma in merino sheep in the South Western Cape

Ten per cent of a flock of 481 Merino sheep died from suspected lymphosarcoma in the Caledon district, during a period of one year. In 9 sheep the diagnosis was confirmed by histopathological examination of the tumours. All the sheep and the cattle on the farm were tested for enzootic bovine leukosis using a Bovine Leukemia Glycoprotein Immunodiffusion kit. At the first test 20.5% of the sheep had antibodies to enzootic bovine leukosis. A control programme resulted in a drop in infection rate (3%) within 17 months.

Dermatosparaxis in White Dorper sheep

A diagnosis of dermatosparaxis in a lamb with clinical signs of extreme skin fragility was based on the gross changes as well as on light and scanning electron microscopical observations. Similar cases had occurred on the same farm during the previous year.

An unusual intrapartum fetal heart rate pattern. A case report

An unusual fetal heart rate pattern was detected intrapartum in a patient with an otherwise uncomplicated pregnancy. An approach to the evaluation of the unusual fetal heart rate pattern was developed.

Antigens of activated rat T lymphocytes including a molecule of 50,000 Mr detected only on CD4 positive T blasts

Mouse monoclonal antibodies (MAbs) have been prepared against rat T cell blasts. One MAb called MRC OX-40 recognized an antigen that differed from any previously described in that its expression was detected only on T blasts that also expressed the CD4 antigen. The OX-40 MAb did not detect an activation determinant of CD2 or CD4 molecules but recognized a distinct chain of mol. wt 50,000. The OX-40 MAb augmented T cell proliferation at late stages on in vitro responses. Other MAbs without obvious counterparts in other species were MRC OX-48 and MRC OX-49,50 which recognized cell surface molecules of mol. wts of about 95,000 and 90,000, respectively. The OX-48 antigen was not expressed on resting lymphocytes but was found on a subset of T and B blasts and also on other leucocytes. The OX-49,50 antigen was found on most haemopoietic cells but was expressed at greatly increased levels after lymphocyte activation and this was also the case for MRC OX-47 antigen which is of unknown Mr. The MRC OX-39 MAb was found to bind the rat IL-2 receptor; expression of this antigen was detected on thymic dendritic cells as well as on T blasts. The phenotype of rat T blasts compared to resting cells was also examined and changes in expression of L-CA, Thy-1, OX-2 and CD8 antigens were seen in addition to the changes found with the above MAbs.

The assessment of bone formation and bone resorption in osteoporosis: a comparison between tetracycline-based iliac histomorphometry and whole body 85Sr kinetics

Bone formation and resorption have been measured in patients with idiopathic osteoporosis by histomorphometry of 7.5-mm trephine biopsies and in the whole body by 85Sr radiotracer methodology and calcium balances. The studies were synchronized and most were preceded by double in vivo tetracycline labeling. Correlations between histological and kinetic bone formation indices were better when better when based on the extent of double tetracycline labels than on measurements of osteoid by visible light microscopy. Correction of the kinetic data for long-term exchange, using 5 months' serial whole body counting of retained 85Sr, improved the fit of the kinetic to the histological data. A statistical analysis of the measurement uncertainties showed that the residual scatter in the best correlations (between exchange-corrected bone formation rates and double-labeled osteoid surface indices) could be attributed to measurement imprecision alone. The exchange-corrected resorption rate correlated fairly well with iliac trabecular resorption surfaces, and using a volume referent rather than a surface referent for the histological index improved the statistical fit when patients with therapeutically accelerated bone turnover were included. A much better correlation was obtained by including osteoid volume acting as an independent predictor of bone resorption in a bivariate regression with a resorption surface index. The residual errors could then be accounted for by known measurement uncertainties. Whereas osteoid taking a double label closely predicted the kinetic rate of bone formation, further analysis suggested that osteoid that took no label or a single label was more closely related to bone resorption, presumably as a secondary result of the coupling of bone formation to bone resorption. The idea that continued bone loss in some patients is associated with defective osteoblastic bone formation is supported by the low rates found in some patients by both techniques. Heuristically these studies validate both in vivo tetracycline labeling for dynamic histomorphometry and corrections for long-term exchange in kinetic studies of bone formation, providing a quantitative framework for the design and analysis of future studies of bone remodeling in the osteoporoses.

Periodic courses of human 1-34 parathyroid peptide alternating with calcitriol paradoxically reduce bone remodelling in spinal osteoporosis

In an attempt to achieve an anabolic response in both axial and peripheral bone, we treated twelve patients with osteoporosis using human 1-34 parathyroid peptide given discontinuously. The peptide was given as seven daily subcutaneous injections followed by 21 days' treatment with 0.25 mg calcitriol orally. This regime was repeated cyclically for at least sixteen cycles, of which the first four were at a lower dose of hPTH 1-34 than used subsequently. The results of treatment were monitored by kinetic, densitometric, histomorphometric and biochemical studies performed before and during treatment. Two patients developed hPTH 1-34 binding in their plasma during treatment: this was presumed to be due to the development of antibodies. The remainder, instead of increasing their indices of bone turnover as judged by iliac bone histomorphometry, were found to have consistent reductions in trabecular resorption surfaces. The other indices of bone formation and resorption measured showed no change or comparable reductions. The small increases seen in total body calcium were consistent with 'in-filling' of deleted basic multicellular units (BMUs). Because there is no evidence that calcitriol alone causes comparable reductions in activation of bone remodelling in osteoporosis, interruption of treatment with hPTH 1-34 after 7 days may have led to a failure of the activation mechanism to proceed to the resorption stage, with a consequent overall reduction in remodelling activity. This type of treatment regime, with its calcitonin-like effect, might be effective in reducing net bone loss due to imbalance between bone formation and resorption at the BMU level, particularly in patients with increased numbers of BMUs ('high turnover' osteoporosis).(ABSTRACT TRUNCATED AT 250 WORDS)

Estimation of whole body bone resorption rate: a comparison of urinary total hydroxyproline excretion with two radioisotopic tracer methods in osteoporosis

In 37 female patients with primary osteoporosis, urinary hydroxyproline excretion, determined in 18 24-h consecutive complete urine collections was compared with two radioisotopic measurements of bone resorption rate measured simultaneously using 85Sr. A somewhat better fit was obtained when the kinetically determined bone resorption rate was corrected for long-term exchange processes within bone. Regression analysis showed that the intercept of the regression of hydroxyproline excretion on resorption rate, corrected or uncorrected for exchange, was significantly higher than zero at about 100 mumol/day. This is consistent with a substantial fraction of urinary hydroxyproline arising from non-bony sources. Fifteen paired studies were analysed and the results suggested that intra-individual variability in these relationships (when studies were separated by a year or more) were similar to inter-individual variability. We calculated the precision with which an estimate of bone resorption could be determined based on the calculated regressions. As a means of non-invasive quantitation of whole body bone resorption rate, the excretion rate of hydroxyproline, measured over 5 days, for example, appeared competitive with isotopic methods making no correction for exchange and relatively little worse than our exchange corrected method.

Management of term breech presentation

The management of 716 cases of singleton breech presentation occurring at 37 or more weeks of gestational age is reviewed. Beginning in 1980 a trial of external version was offered if the breech was identified before active labor. Only 433 (61%) breeches were identified before active labor. Of these, 171 (44%) underwent an attempt at external version and 83 (48%) were successful. The 623 cases remaining as breech presentation were stratified into three groups: cesarean section without labor (379), trial of labor with cesarean section (69), and trial of labor with vaginal delivery (175). The criteria for allowing a trial of labor are detailed. Careful review of maternal and fetal variables indicates that a trial of labor in selected patients will result in vaginal delivery in 72% and that this can be achieved without an increase in fetal or maternal mortality or morbidity. Furthermore, successful external version followed by a trial of labor in selected cases is highly cost-effective.

Abruptio placentae following nipple stimulation

A case of severe abruptio placentae evolved during the course of prepartum electronic fetal heart rate (FHR) monitoring which was associated with nipple stimulation. The fetal monitor tracing and clinical course are discussed. The unpredictability of abruptio placentae is underscored by the normal appearance of the FHR tracing immediately preceding the event. The association of nipple stimulation with abruptio placentae in this case raises concerns about the potential dangers of this surveillance technique.

Ovine hepatogenous photosensitivity caused by the plant Nidorella foetida (Thunb.) DC. (Asteraceae)

Following a field outbreak of hepatogenous photosensitivity in sheep, an identical condition was reproduced experimentally by dosing 2 sheep with green, homogenized, Nidorella foetida material, collected from the camp where the outbreak occurred. This is a rare, unpalatable, aromatic shrub found in swampy places in the south-western Cape Province. The main lesion was a hepatosis, characterized by peripheral coagulative necrosis and midzonal degeneration in the 2 acute cases and mild bile duct proliferation and hepatic regeneration in the more chronic field case. Botanical, toxicological, clinical and pathological data are given.

Cesarean section prophylaxis: comparison of two doses with three doses of mezlocillin

A prospective randomized double-blind comparison of two doses, with three doses of mezlocillin for nonelective cesarean section prophylaxis was performed. One hundred seven (107) patients were evaluated. Mezlocillin (4 g) was given post-cord clamping and then at 4-h intervals for a total of two doses or three doses. The incidence of febrile morbidity was lower in the three-dose group (2 of 46, 4%) than the two-dose group (14 of 61, 23%) (P less than 0.02). However, the incidence of infectious morbidity was not different between the three-dose group (3 of 46, 7%) and the two-dose group (10 of 61, 16%), and the incidence of endomyometritis was similar in the two groups (6.5% vs 9.8%). Among failures of prophylaxis there were no differences compared to successes in the number of potential commensals or potential pathogens cultured from amniotic fluid. However, the proportion of failures among patients with both commensals and potential pathogens isolated (10/58) was significantly greater than among patients with none or only commensals isolated (1/37) (P less than 0.03). We found mezlocillin to be an effective agent for perioperative cesarean section prophylaxis with two doses as effective as three doses. The presence of clinically important organisms in the amniotic fluid at the time of operation typified patients with postoperative infectious complications despite perioperative prophylaxis.

Specificity studies on enteropeptidase substrates related to the N-terminus of trypsinogen

The specificity of the synthetic substrate Gly-[L-Asp]4-L-Lys 2-naphthylamide originally developed for the assay of enteropeptidase (EC 3.4.21.9), was investigated with partially purified aminopeptidase. Our results indicate that, not only enteropeptidase, but also the concerted action of the aminopeptidases of the rat small intestine, can rapidly release 2-naphthylamine from the substrate. A previously undescribed, highly active, dipeptidylaminopeptidase, which hydrolyses a Gly-Asp dipeptide from the N-terminus of the substrate, was detected in rat small intestine. The resulting [L-Asp]3-L-Lys 2-naphthylamide fragment is then degraded by a combination of aminopeptidase A and N to yield free 2-naphthylamine. Thus the present substrate cannot be regarded as being specific for enteropeptidase, and its use leads to an over-estimation of enteropeptidase activity in homogenates and extracts of intestinal tissue. In order to prevent this non-specific hydrolysis by aminopeptidases, stereoisomeric substrates with the sequence L-Ala-D-Asp-[L-Asp]3-L-Lys methyl ester, D-Ala-[L-Asp]4-L-Lys methyl ester and L-Ala-[Asp]4-L-Lys methyl ester were synthesized and tested as alternative substrates by their ability to inhibit the enteropeptidase-catalysed activation of trypsinogen.