Chemoreflex contribution to adrenocortical function during acute hypoxemia in the llama fetus at 0.6 to 0.7 of gestation

This study tested the hypothesis that the fetal llama, a species adapted to the chronic hypoxia of life at high altitude, demonstrates a potent carotid chemoreflex influence on adrenocortical responses during acute hypoxemia. Plasma ACTH and cortisol concentrations, and mesencephalic and adrenal blood flows were measured during a 1-h period of acute hypoxemia in six intact and four carotid sinus-denervated llama fetuses at 0.6-0.7 of gestation. Fetal PaO2 was reduced from approximately 23 to about 14 mm Hg in both intact and carotid-denervated groups during acute hypoxemia. During hypoxemia, fetal plasma ACTH, adrenal blood flow, and, therefore, delivery of ACTH to the adrenals increased to similar extents in both intact and carotid-denervated fetal llamas. Despite this, the increase in plasma cortisol in hypoxemia in intact fetuses was absent in carotid-denervated fetuses. In addition, the increase in delivery of cortisol to the mesencephalon calculated in intact fetuses during hypoxemia did not occur in the carotid-denervated group. These data suggest that the integrity of the carotid chemoreceptors is indispensable to cortisol release during acute hypoxemia in the llama fetus, even at 0.6-0.7 of gestation.     

Thermodynamic regulation of cytochrome oxidase

This study tested the hypothesis that in the llama fetus changes in cerebral blood flow are closely associated with changes in cerebral oxidative metabolism such as occur during transitions between electrocortical states. For the first time reported in any species, instantaneous changes in common carotid blood flow, employed as a continuous index of cerebrovascular perfusion, were related to instantaneous changes in electrocortical activity. Three late gestation fetal llamas were surgically prepared under general anesthesia with vascular catheters, a tracheal and amniotic catheter, and with electrodes implanted to monitor the fetal electrocorticogram (ECoG). In addition, Transonic flow probes were placed around a common carotid artery and a femoral artery. At least 4 days after surgery fetal arterial blood, amniotic and tracheal pressures, carotid and femoral blood flows and the fetal ECoG were recorded continuously. Our results suggest a close association between increases in common carotid blood flow and low voltage ECoG in the llama fetus. Close coupling between instantaneous changes in carotid blood flow and electrocortical states together with the lack of an increase in brain blood flow without increased cerebral oxygen extraction during hypoxemia in the llama fetus supports a fall in cerebral oxidative metabolism in this species during hypoxemic episodes.     

Gastrointestinal ulceration and pulmonary aspergillosis in a llama treated for parelaphostrongylosis

A 9-year-old llama examined because of hind limb paresis was found to have parelaphostrongylosis. Despite treatment with ivermectin, fenbendazole, cimetidine, and ceftiofur, the llama developed gastrointestinal ulceration and pulmonary aspergillosis and was euthanatized. Parelaphostrongylus tenuis is a parasite of white-tailed deer, but ruminants can serve as aberrant or dead-end hosts after accidentally ingesting snails or slugs carrying third-stage larvae of the parasite. Gastrointestinal ulceration and pulmonary aspergillosis can develop secondarily in llamas with chronic disease. Treatment of gastrointestinal ulceration in llamas is difficult, because efficacy of commonly used antiulcer drugs in llamas has not been established.     

Comparison of llama VH sequences from conventional and heavy chain antibodies

Forty different PCR clones encoding a llama variable heavy chain domain were analysed. The majority of these clones are derived from heavy-chain antibody cDNA in which the entire CH1 exon is absent. It appears from the amino acid within the VHH framework 1 and 3 that all the llama clones belong to the VH III family. However, the individual llama VHH sequences differ more substantially from each other than expected for members of the same family. Several remarkable amino acid substitutions in the framework 2 hinder the proper association of the VL. However, they lay the foundation for the secretion from the endoplasmic reticulum and good solubility behaviour of llama H2 antibodies. The repertoire of the llama VHHs may be extensive due to the presence of a long CDR3-loop, often constrained by a disulfide bridge and the occurrence of H1 and H2 loop conformations not yet encountered in mice or human VHs. The variability plot of the amino acids in the VHH shows that the first hypervariable region coincides with the structural H1 loop in contrast to the situation found in mice and man where the CDR1 and H1 are slightly offset. We propose that the amino acids of the llama H1 loop participate actively in the antigen binding. All these observations are characteristic for the llama VHHs of the homodimeric heavy-chain H2 antibodies, but are not maintained in the llama clones from conventional heterotetrameric H2L2 immunoglobulins.     

Suspected nutritional deficiency causing anaemia in llamas (Lama glama)

A case of poor condition and recumbency in a 14-month-old female llama and a case of poor condition and ataxia in a 23-month-old male llama are described. Both animals were anaemic and had low plasma copper levels. An increased intake of feed with a higher copper level and treatment with copper injections and an oral mineral solution resulted in a successful recovery. Two other young llamas also had low plasma copper levels. The problem was probably due to a nutritional, particularly copper, deficiency and the animals recovered as their copper levels increased.     

Surgical repair of patellar luxation in llamas: 7 cases (1980-1996)

OBJECTIVE: To evaluate anatomy of the stifle in llamas and determine outcome of llamas that underwent surgery for repair of patellar luxation. DESIGN: Anatomic and retrospective study. ANIMALS: 6 llamas with unilateral patellar luxation and 1 llama with bilateral luxations. PROCEDURE: 6 stifles from llama cadavers were dissected to determine anatomy. Medical records were reviewed to identify history, procedure, outcome, and complications of llamas that underwent surgery. RESULTS: 6 llamas had lateral patellar luxation (including the llama with bilateral luxations), and 1 had medial patellar luxation. Six llamas had a history of trauma before onset of clinical signs. Two llamas underwent tibial tuberosity transposition, but luxation recurred in both and 1 had problems with breakage of implants. The other 5 llamas underwent imbrication and release procedures; however, luxation recurred in 4 of the 5. Surgery was repeated in 2 llamas, with successful outcomes. CLINICAL IMPLICATIONS: Results suggest that imbrication and release procedures may be useful for correction of patellar luxation in llamas without other bony abnormalities. However, long (20 cm) imbrication and release incisions are needed for a successful outcome. Use of a sling after surgery, to allow a gradual return to weight bearing and exercise, may also be important.     

Molecular evolution of the family Camelidae: a mitochondrial DNA study

We report the first molecular evolutionary analysis of the family Camelidae by analysing the full DNA sequence of the mitochondrial cytochrome b gene. Estimates for the time of divergence of the Old World (Camelini) and New World (Lamini) tribes obtained from sequence data are in agreement with those derived from the fossil record. The DNA sequence data were also used to test current hypotheses concerning the ancestors of the domesticated llama and alpaca. The results show that hybridization has occurred in the ancestry of both domesticated camelids, obscuring the origin of the domestic species.     

Reducing headaches after a myelogram

Presented here is the first report of a pregnancy complicated by symptomatic polycystic liver disease. Associated abdominal pain necessitated transcutaneous hepatic cyst aspiration at 5, 13, 20, 24, 30, and 34 weeks' gestation. Labor was induced at 35 weeks' gestation after confirmation of fetal pulmonary maturity.     

Evaluation of serum gamma-glutamyltransferase activity as a predictor of passive transfer status in crias

OBJECTIVE: To determine the relationship between serum gamma-glutamyltransferase (GGT) activity and serum IgG concentration in neonatal crias. DESIGN: Prospective observational study. ANIMALS: 21 llama and 4 alpaca crias from 0 to 5 days old. PROCEDURE: Serum GGT activity was measured, using a commercially available kit. Serum IgG concentration was determined by use of radial immunodiffusion. With a serum IgG concentration of 1,000 mg/dl (considered adequate passive transfer), specificity and sensitivity of serum GGT activity in the detection of failure of passive transfer were determined. Regression models were developed to determine the relationship between serum GGT activity and serum IgG concentration. RESULTS: Sensitivity ranged from 0.56 to 0.89, and specificity ranged from 0.88 to 0.31, depending on the value of serum GGT activity chosen as a threshold. Proportion of crias correctly classified ranged from 0.76 to 0.52. Regression models failed to demonstrate a significant relationship between serum GGT activity and serum IgG concentration. CLINICAL IMPLICATIONS: Passive transfer status in crias cannot be accurately predicted on the basis of serum GGT activity.     

Delayed-interval delivery in a quadruplet pregnancy after intrauterine death of a partial molar pregnancy and preterm delivery. A case report

BACKGROUND: Delayed-interval delivery is infrequent in twin gestation and more rare in triplet and quadruplet gestation. Coexistence of a triploid pregnancy with a normal fetus has not previously been reported to have resulted in survival of the normal fetus. CASE: A 26-year-old woman, gravida 2, para 0-0-1-0, was diagnosed with a quadruplet pregnancy. At 16 1/2 weeks' gestation she developed preeclampsia and severe hyperemesis. Ultrasound was consistent with partial molar pregnancy in quadruplet D. Quadruplet D died in utero, and the preeclampsia and hyperemesis resolved. At 19 5/7 weeks, spontaneous rupture of the membranes and preterm labor occurred, and quadruplet A, stillborn female weighing 260 g, was delivered. With the use of antibiotic therapy, tocolysis and bed rest, the remaining two fetuses were maintained in utero until 32 6/7 weeks' gestation, when quadruplet B, a 1,470-g female, and quadruplet C, a 1,700-g female, were delivered. CONCLUSION: This was the first reported case of surviving fetuses coexisting with a partial molar pregnancy. This case was also complicated by preterm delivery and successful delayed-interval birth in a quadruplet pregnancy.     

Heterologous radioimmunoassay for llama and alpaca luteinizing hormone with a monoclonal antibody, an equine standard and a human tracer

A radioimmunoassay for llama and alpaca LH was developed using a human I125LH tracer from a commercial kit, equine LH diluted in human LH free serum as standard, and a monoclonal antibody (518B7) specific for LH but with low species specificity. A 60-min delay in the addition of the tracer and overnight incubation gave a sensitivity of 0.8 microgram L-1. The intra-assay coefficient of variation was 37% at 1 microgram L-1, declined to 15% at 4 micrograms L-1 and was below 6% for concentrations up to 32 micrograms L-1. The inter-assay coefficients of variation for 3 control samples were 20% (2.8 micrograms L-1), 16% (7.1 micrograms L-1) and 9.8% (19 micrograms L-1). In an attempt to increase sensitivity, all tubes were preincubated for 4 h at room temperature before adding the tracer, and the sample volume was increased from 50 microL to 100 microL (in the standard curve the increased volume was compensated for by human LH free serum). With this protocol, the assay sensitivity was 0.5 microgram L-1. The assay was validated clinically and demonstrated increased concentrations of LH after mating in llamas and alpacas. Furthermore, the assay was used to monitor LH responses to a single dose of GnRH in llamas (adult males and females at different ages).     

Regulation of rat hepatic 3 alpha-hydroxysteroid dehydrogenase in vivo and in primary cultures of rat hepatocytes

Lamoids in North America harbor a wide variety of parasites. Treatment and control methods based on previous experience with parasites of cattle and sheep have been successful, but problems do exist. First, the pharmacokinetics for most anthelmintics have not been evaluated in llamas. Second, even though llamas, sheep, and cattle share many parasites, the two most common nematodes found in llamas (C. mentulatus and T. tenuis) are not part of the parasitic fauna of livestock. This presents difficulties in basing treatment and control methods on those recommended for cattle and sheep. Variability in host response to the same parasite also hinders the use of cattle and sheep as models for the llama. This is best demonstrated by F. magna and F. hepatica; the reaction induced by the first more closely resembles those seen in cattle than sheep, but the reaction induced by the second more closely resembles those seen in sheep than cattle. Finally, parasites known to be pathogenic in livestock (e.g., N. battus) have unknown effects in llamas. These examples illustrate that we must use caution when extrapolating existing knowledge regarding the parasites of sheep and cattle to llamas. Further research on the epidemiology of parasites peculiar to the llama is needed to enhance control efforts. Improved methods of diagnosis and treatment of parasites also are areas in which further efforts are needed.     

Somatic sensory cortex of llama (Lama glama)

The somatic sensory cortex (SI and SII) was mapped in llamas using microelectrode mapping methods developed earlier in a study of SI of the slow loris. Projections to SI from the llama's prehensile browsing lips were differentially enlarged when compared to those reported for sheep. In llama, SII was reversed in its mediolatreal pattern from that reported for SII in most other mammals. Fissural landmarks reliably demarcated different projections within SI, between SI and SII and between SI or SII and other surrounding nonsensory areas. The use of microelectrode mapping methods in different mammals to determine gyral and fissural homologies is discussed.     

What makes a life good?

OBJECTIVE: The objective of this study was to evaluate the longitudinal changes in energy expenditure and body composition in relationship to alterations in carbohydrate metabolism in women with normal and abnormal glucose metabolism. We hypothesized that women with decreased insulin sensitivity before conception would have less fat accretion and smaller increases in energy expenditure. STUDY DESIGN: Six women with normal glucose tolerance and 10 women with abnormal glucose tolerance were evaluated before conception, and in early (12 to 14 weeks) and late (34 to 36 weeks) gestation. Body composition was estimated by hydrodensitometry, resting energy expenditure, and glucose and fat metabolism by indirect calorimetry, endogenous glucose production by infusion of [6-6 2H2] glucose, and insulin sensitivity using a hyperinsulinemic-euglycemic clamp (40 mU/m2/min). RESULTS: There was a smaller increase in fat mass (1.3 kg [P = .04]) in early pregnancy in women with abnormal glucose tolerance before pregnancy. Indirect calorimetry measured gestational age-related increases in basal oxygen utilization, with or without correction for fat-free mass (VO2, P = .002), resting energy expenditure (expressed in kilocalories, P = .0001), and carbohydrate oxidation (P = .0003). The insulin-mediated elevation in VO2 increased in later gestation VO2 (P = .005), as did resting energy expenditure (P = .0001) and fat oxidation (P = 0.0001). However, there was a decrease in respiratory quotient (P = .0001), carbohydrate oxidation (P = .002), and nonoxidative carbohydrate metabolism (P = .0001) with advancing gestation during insulin infusion. In early pregnancy, changes in fat mass correlated inversely with changes in insulin sensitivity (r= -0.52, P = .04) and changes in basal VO2 correlated inversely with decreases in basal endogenous glucose production (r = -0.74, P = .01). CONCLUSION: In early gestation, the changes in maternal fat mass and basal oxygen consumption are inversely related to the changes in insulin sensitivity. This response in lean women with decreased insulin sensitivity before conception may have survival value by providing a larger amount of available substrate to meet fetoplacental needs during gestation.     

In utero exchange transfusion in homozygous alpha-thalassaemia: a case report

We report a case of homozygous alpha-thalassaemia with hydrops fetalis presenting at 22 weeks of gestation. In utero exchange transfusion was performed with maternal blood at 23 weeks. 25 weeks and 29 weeks of gestation. The fetus was delivered at 29 weeks of gestation without significant neonatal complication. Post-transfusion haemoglobin pattern after transfusion suggested that a total haematocrit of 0.52 may be the desired post-exchange transfusion haematocrit to aim for and the total haematocrit of haemoglobin A and haemoglobin Portland dropped approximately one percent per day.     

Cardiomyopathy and pre-excitation syndrome of a familial nature

Amniotic fluid insulin levels and the lecithin-sphingomyelin ratio were determined in 62 samples of 33 insulin-dependent diabetic patients from the 29th to the 44th week of gestation inclusive and in 42 samples of 38 gestational diabetic patients from the 35th to the 43rd week of gestation inclusive. (Gestational age was measured by ultrasonography.) The level of insulin in the amniotic fluid did not appear to affect the lecithin-sphingomyelin ratio.     

Nitric oxide synthase activity in the gravid rat uterus decreases a day before the onset of parturition

OBJECTIVE: Our purpose was to determine the timing, tissue location, and isoform of the uterine nitric oxide synthase activity decrease at term in gravid rat uteri. STUDY DESIGN: Nitric oxide synthase specific activity was assayed in rat uteri 11 through 22 days' gestation by the difference in radiolabeled arginine to citrulline conversion with and without the cofactor reduced nicotinamide adenine dinucleotide phosphate. Nitric oxide synthase isoform was assessed by calcium sensitivity and subcellular location. RESULTS: Rat uterine nitric oxide synthase activity decreased between days 15 and 21 of gestation but did not decrease further at term (day 22), before and after the onset of labor. Decidual nitric oxide synthase activity exceeded the myometrial activity at 15 days' gestation, but then the two were equal at 18 through 22 days' gestation. The nitric oxide synthase activity was calcium insensitive except for half the decidual cytosolic activity on day 15. CONCLUSION: The decrease in pregnant rat uterine nitric oxide synthase activity coincides with the preparation of the uterus for parturition rather than the final activation of labor.     

Identifying twin gestations at low risk for preterm birth with a transvaginal ultrasonographic cervical measurement at 24 to 26 weeks' gestation

OBJECTIVE: Because twins are a high-risk group for preterm birth, many clinicians routinely use prophylactic interventions such as home bed rest, hospital bed rest, oral tocolytics, or home uterine activity monitoring to prevent preterm delivery. We sought to identify twin gestations at low risk for spontaneous preterm birth with transvaginal ultrasonography of the cervix to avoid the unnecessary use of prophylactic interventions in these pregnancies. STUDY DESIGN: We measured cervical length at 24 to 26 weeks' gestation by transvaginal ultrasonography in women with twin gestations referred to our prematurity prevention clinic. Each delivery was classified as (1) spontaneous preterm birth < 34 weeks' gestation, (2) delivery at > or = 34 weeks' gestation with intervention, or (3) delivery at > or = 34 weeks' gestation without intervention. Intervention included strict bed rest at home or in the hospital, either parenteral or oral tocolysis, or both, or home uterine activity monitoring. Indicated preterm deliveries and patients with cerclage were excluded from this analysis. The ability of transvaginal cervical length to predict women who would deliver at > or = 34 weeks without intervention was evaluated. A cervical length of 35 mm was chosen by scatter diagram as the best cutoff to discriminate between the group delivered at term without intervention and the other two groups. RESULTS: Of 85 women with twin gestations who underwent ultrasonographic cervical length measurements at 24 to 26 weeks' gestation, 17 had spontaneous preterm birth at < 34 weeks, 23 were delivered at > or = 34 weeks but required intervention, and 45 were delivered at > or = 34 weeks without intervention. The mean cervical length for those delivered at > or = 34 weeks' gestation without intervention (36.4 +/- 5.8 mm) was significantly greater (p < 0.0001) than the mean for those delivered preterm (27.4 +/- 8.5) and those delivered at > or = 34 weeks' gestation who required intervention (27.7 +/- 10.5 mm). The sensitivity, specificity, and positive and negative predictive values of a cervical length > 35 mm for predicting delivery at > or = 34 weeks' gestation are 49%, 94%, 97%, and 31%, respectively. CONCLUSION: A transvaginal ultrasonographic measurement of the cervix of > 35 mm at 24 to 26 weeks in twin gestations can identify patients who are at low risk for delivery before 34 weeks' gestation.     

Abnormal twin pregnancy--early resorption of a single fetus in a twin pregnancy pregnancy]

INTRODUCTION: Twin pregnancy presents a condition of development of two fetuses in the uterus and can be monozygotic (single ovum) and dizygotic (two ova). In case of fertilization and segmentation of one ovum monozygotic twins are produced, while in case of fertilization of two ova, which can originate from one or two Graff follicles, dizygotic twins are developed. The ratio of twin and single pregnancies is 1:89 (according to Hellin's law) (1). The incidence of twin and other multiple pregnancies is influenced by: race of parents, age and parity of mother, use of clomid and gonadotrophin to stimulate ovulation, discontinued use of contraceptive pills and certain seasons (exposure to sunlight) (1). Due to occurrence of numerous complications twin pregnancy and parturition are considered to be highly risky. This is supported by clinical data on more frequent spontaneous abortions--especially in monozygotic pregnancies, hypertension in pregnancy, hemorrhage of various etiologies, anemias, early rupture of amniotic membranes, hydramnios, premature deliveries, etc. Nowadays diagnosis of both twin and other multiple pregnancies in the early stage is required, in order to establish normal or pathological development of such pregnancies. As early as 6 gestation week in twin pregnancies it is possible to sonographically visualize two gestation sacs in the uterus, while in 7-8 gestation weeks it is possible to see two embryos with evidence of fetal heart rate. In early pregnancy a differentially-diagnosed uterus may be clinically enlarged due to: hydratidaform mole, uterine mioma or ovarian cyst. In later gestation confirmation of twin pregnancy is possible by clinical and sonographic examination and biochemical analyses (elevated values of HPL and -fetoprotein) and less frequently, by x-ray. Repeated sonographic examinations can reveal the following anomalies of twin pregnancies: one normal pregnancy with one sac containing no embryo, one sac containing no embryo and one sac with a dead fetus, fetuses without vitality in both gestation sacs, two ultrasound echoes from which only one normal fetus and one dead mummified fetus (fetus papiraceus) result within the uterus. One gestation sac may be resorbed during pregnancy, while the undamaged fetus continues to develop normally in the uterus. In certain cases the loss of one fetus is not accompanied by any clinical symptoms, and in others this can be accompanied by light hemorrhage. An initial twin pregnancy after the loss of one twin may end by a birth of one healthy infant. CASE REPORT: A patient aged 35 years, came for gynecological examination due to missed menstruation. Ananmesis showed that she had a nascent uterine myoma which was removed by myomectomy six months earlier, had one parturition four years earlier, and no abortions. The last menstrual period was on February 12, 1991. Clinical examination showed a somewhat larger uterus than would be normal for amenorrhea of 9-gestation week. By sonographic examination two regular gestation sacs were found in the uterus with fetal echoes present as well as heart rate in both fetuses (Figure 1). Embryo measurements were as follows: Fetus 1-CRL-22.5 mm, NEG-8 + 4, heart rate present. Fetus 2-CRL-23.6 mm, NEG-9, heart rate present (Figure 2). The patient was cautiously informed that two fetuses are visible in the uterus and that this is a sign of twin pregnancy, but for certain diagnosis a control examination was scheduled two weeks later. The sonographic examination after 14 days later showed discord in fetal growth (Figure 3). Embryo measurement in 11-gestation week rendered the following parameters: Fetus 1-CRL-22.8 mm, NEG 8 + 6, no heart rate registered (Figure 4), while the second fetus continued to develop and had the following characteristics: Fetus 2-CRL-50.5 mm, NEG 11 + 4, heart rate and fetal movement registered (Figure 5). During entire pregnancy the patient suffered no pain or any kind of hemorrhage. She took no drugs. (ABST     

Pregnancy in a Jehovah's witness with cervical cancer and anemia

A 34-year-old Jehovah's Witness presented with vaginal bleeding and anemia at 23 weeks gestation. She was diagnosed with a FIGO Stage IB2 squamous cell carcinoma of the cervix. The patient refused transfusion of blood products and strongly desired to continue the pregnancy. She was hospitalized and at 33 weeks gestation underwent a Cesarean-radical hysterectomy with measures that minimized blood loss.