Single Injection Group Research Articles

The number of injections does not influence absorption of bupivacaine after cervical plexus block for carotid endarterectomy

Study ObjectiveTo investigate the efficacy and kinetics of bupivacaine when used for deep cervical plexus block (CPB), using either a single-injection or multiple-injections technique. DesignProspective, randomized, double-blind study. SettingOperating room of a university hospital. PatientsTwenty-four adult patients (16 men, 8 women) scheduled for carotid endarterectomy. InterventionsPatients were randomly assigned to receive CPB either by a single injection or after 3 injections. Patients in the multiple-injections group received a total dose of 15 mL of 0.5% bupivacaine (5 mL each deposited at C2, C3, and C4 over 2 minutes). Patients in the single-injection group received a single 15-mL injection of 0.5% bupivacaine. After the deep CPB, a superficial CPB was performed with 20 mL of 0.5% bupivacaine in all patients. MeasurementsAn anesthesiologist and a surgeon graded the success of the block. Arterial plasma concentrations of bupivacaine were measured using liquid chromatography–mass spectroscopy. Main ResultsNo significant differences were seen between the 2 groups with respect to the mean peak concentration of bupivacaine (single injection 2314 ± 1385 ng/mL vs multiple injections 2255 ± 1105 ng/mL) or time to reach the maximal concentration (time to maximum concentration [single injection 12.1 ± 7.2 minutes vs multiple injections 12.5 ± 3.9 minutes]). Furthermore, there were no significant differences in mean block scores between the single-injection and the multiple-injections groups, evaluated either by the anesthesiologists or the surgeon. ConclusionsThe results of this study showed that the absorption of bupivacaine is independent of the number of injections after CPB, and that anesthesia for carotid endarterectomy may be accomplished successfully using either technique.

Induced ovulation and embryonic development of ocellated puffer, Takifugu ocellatus

Summary Acute injections of different hormones to induce ovulation in mature ocellated puffer, Takifugu ocellatus, collected from natural waters during the spawning season, were carried out to develop a reliable protocol for mass production of seed in this species. All experimental fish were divided into seven groups treated with: a saline injection (control), single or two injections of luteinizing hormone-releasing hormone analog (LHRH-a; single injection: 50 μg kg−1, two injections: 10 and 40 μg kg−1), single or two injections of pituitary (single injection: 6 mg kg−1, two injections: 1 and 5 mg kg−1) and single or two injections of human chorionic gonadotropin (hCG; single injection: 2500 IU kg−1, two injections: 500 and 2000 IU kg−1), respectively. The percentage of fish that ovulated in six hormonal treatments reached 100%, either with a single injection or with two injections whereas the fish in control group failed to spawn. There were no significant differences among all hormonal treatments in egg production, fertilization rate, or hatch rate (P > 0.05) except time to ovulation between a single injection group and the two-injection group (P < 0.05). The fertilized eggs of ocellated puffer were spherical, demersal, and adhesive. They had a mean oocyte diameter of 1.487 ± 0.106 mm (range: 1.404–1.560). The egg membrane was transparent and yolk was buff in color, containing a cluster of small oil globules. Thirty-four successive stages of embryonic development were identified and characterized. Fertilized eggs incubated at 18–20°C generally commenced hatching at 144 h after fertilization. Newly hatched larvae were about 3.26–3.45 mm in length. The induced ovulation technique using acute injections of hormones is an important step in the development of the culture of the ocellated puffer.

Gene expression of bone-resorbing cytokines in rat osteolysis model

Osteolysis after single-injection polyethylene (PE) administration has been analyzed, but this experimental model did not reflect the clinical postoperative condition. Therefore, we investigated the bone-resorbing cytokines interleukin and tumor necrosis factor (IL-1a, IL-6, TNFa) produced by continuous PE administration using histomor- phologic findings and the reverse transcription polymerase chain reaction. TNFa mRNA was continuously detected in the PE continuous-infusion group, whereas it was not expressed in the PE single-injection group. IL-1a and IL-6 mRNA were detected in both groups. As for histomor- phological findings, in the PE continuous-infusion group proliferating fibrous tissue penetrated subchondral bone and the interface membrane around the K-wire inserted into the femur. Numerous osteoclasts were observed in the vicinity of resorbed bone. In the PE single-injection group, proliferation of fibrous tissue with bone resorption was not observed. TNFa may play a major role in fibrous tissue formation and osteoclastic bone resorption caused by PE debris. This osteolysis model is useful for investigating osteolysis associated with bone-resorbing cytokines under conditions similar to those seen with a human prosthesis.

Measurement of skeletal muscle glucose utilization by dynamic 18F-FDG PET without arterial blood sampling

Skeletal muscle glucose utilization (SMGU) can be measured by 18F-FDG PET to characterize insulin resistance. The aim of this study was to determine whether femoral muscle SMGU can be measured without arterial blood sampling by sequential PET imaging of the thoracic and femoral regions. Ten patients with possible insulin resistance underwent dynamic 18F-FDG PET of the femoral region during hyperinsulinaemic euglycaemic clamping (group A), and femoral muscle SMGU was calculated using PET data of various time periods and measured arterial input. SMGU was also calculated using venous plasma activity, instead of arterial activity, as input during the late phase. Another five patients underwent sequential PET of the thoracic and femoral regions after single tracer injection (group B). The input function was estimated from aorta activity on thoracic images during the early phase and from venous activity during the late phase, and SMGU with this estimated input was compared with that with measured arterial input. In group A, exclusion of early dynamic PET data from analysis had essentially no effect on the calculated SMGU, and partial substitution of venous activity for arterial activity only marginally changed the estimates. The difference between SMGUs with measured and estimated inputs was minimal in group B. Femoral muscle SMGU can be calculated without femoral imaging early after tracer injection, and the input function can be assessed using data of thoracic imaging and venous blood samples. These results support the validity of measuring femoral muscle SMGU without arterial sampling, simultaneously with measurement of myocardial glucose utilization.

Evaluation of cervical arteries with 3D-CTA using multi-detector row CT—one-session scanning of the head and neck using single or double injection of contrast medium

To detect cervical vascular lesions in 90 patients with intracranial cerebrovascular diseases, we performed three-dimensional CT angiography (3D-CTA) of the head and neck using multi-detector row CT (MD-CT) with a single- or double-bolus injection of contrast material. In the single-injection group ( n=70), the head and neck were scanned in one session after continuous injection at a rate of 3 ml/s of contrast medium (total 100 ml). In the double-bolus injection group ( n=20), the head was scanned first after the delivery of contrast material (3 ml/s, total 70 ml) and the neck was scanned after a boost injection (2 ml/s, total 30 ml). The single-bolus injection method was simple and suitable for screening for vascular lesions at the carotid bifurcations. The double bolus injection method yielded excellent 3D-CTA of the vertebral- and carotid arteries without interference by cervical veins and was suitable for screening the whole length of the carotid arteries, including the origin of the vertebral arteries. The head and neck 3D-CTA using MD-CT provides valuable diagnostic information regarding vascular lesions of the intracranial and cervical arteries.

Comparison of the Parasacral Approach and the Posterior Approach, with Single- and Double-Injection Techniques, to Block the Sciatic Nerve

The purpose of this study was to compare parasacral and Winnie's single- or double-injection approaches for sciatic nerve block. One hundred fifty adults scheduled to undergo lower limb surgery were randomized to receive on the sciatic nerve 20 ml ropivacaine, 0.75%: single bolus for parasacral and Winnie's single injection. For Winnie's double injection, the peroneal and tibial nerves received separately 10 ml plus 10 ml. Blocks were performed with the use of nerve stimulator (intensity < 0.5 mA, 1 Hz). For the parasacral method, a line was drawn between the posterior superior iliac spine and the ischial tuberosity; needle entry was at 6 cm inferior to the posterior superior iliac spine. The groups were similar. Time to perform the block was 2 (1-5) min for the parasacral method, with no difference from Winnie's single injection (3 [1-10] min), but was shorter with double injection (5.5 [2-15] min) (P = 0.0001). Onset of sensory block was similar in the parasacral (25 [7.5-50] min) and Winnie single-injection groups (25 [5-50] min) but significantly longer in the double-injection group (15 [5-50] min). Success rates for complete block were similar in the parasacral (66%) and Winnie's double-injection groups (68%) after 30 min but higher in the Winnie's single-injection group for tibial sensory and motor block (48%) (P < 0.017). Time to perform a parasacral block was short, and the parasacral approach had a high success rate and a short onset time. Therefore, this block might be a useful alternative to Winnie's modification for sciatic nerve block.

Reactogenicity of DTPa–HBV/Hib vaccine administered as a single injection vs DTPa–HBV and Hib vaccines administered simultaneously at separate sites, to infants at 2, 4 and 6 months of age

An open, randomised, multicentre trial was performed to assess the reactogenicity and safety profile of the administration of a candidate Haemophilus influenzae type b (Hib) conjugate vaccine with a quadrivalent diphtheria–tetanus–acellular pertussis–hepatitis B (DTPa–HBV) vaccine as a single injection (Group 1) versus the simultaneous administration of the latter vaccine (DTPa–HBV) and an available Hib conjugate vaccine (Group 2) in opposite thighs, as a primary vaccination course to healthy infants at 2, 4 and 6 months of age. Eight hundred and eighty five infants (9.3±1.4 weeks old) were randomly allocated to Group 1 ( n=665) and Group 2 ( n=221). Oral polio vaccine was given concomitantly to all subjects. Blood samples (pre-vaccination and 1 month after the third dose) were obtained from a subset of infants (Group 1, 73; Group 2, 22) for serological determinations. Local and general symptoms were recorded by parents on diary cards. 2614 diary cards (Group 1, 1966; Group 2, 648) were collected. There were no statistically significant differences in the incidence of local and general symptoms between groups. Pain such that the infant cried when limb was moved was reported in 0.6 and 0.2% in groups 1 and 2, respectively. Redness and swelling (>20 mm in diameter) were recorded between 2.1 and 3% in both groups. Fussiness preventing normal activities was the most frequently reported general symptom in both groups (1.6 and 1.9% in groups 1 and 2, respectively). Fever (rectal temperature >39.5°C) was reported in 0.4% (Group 1) and 0.3% (Group 2). All subjects included in the immunogenicity analysis had seroprotective or seropositive titres to the diphtheria, tetanus, hepatitis B and pertussis components of the vaccines. About 99 and 100% of infants had anti-PRP titres ≥0.15 mcg/ml in groups 1 and 2, respectively. This study indicates that DTPa–HBV vaccine given in a single injection with a candidate Hib conjugate vaccine has a similar reactogenicity profile to that of two commercially available vaccines (DTPa–HBV, Hib) given in two simultaneous injections to infants 2, 4 and 6 months of age .

Aberrant expression of cyclin D1 in pulmonary proliferative lesions induced by high doses of urethane in transgenic mice carrying the human prototype c-H-ras gene.

In our previous study, when rasH2 mice and non-transgenic (non-Tg) littermates were injected intraperitoneally with 1,000 mg/kg of urethane once or three times at two-day intervals, the incidence of lung proliferative lesions in rasH2 mice given triple doses of urethane was significantly increased, compared to that in rasH2 mice given a single dose of urethane, and the mutation frequency of the transgene in lung tumors in rasH2 mice given triple doses was lower than that in rasH2 mice given a single dose of urethane. In the present study, differential immunohistochemical expressions of Cyclin D1 and PCNA, that lead to abnormal cell proliferation and tumor development due to uncontrolled G1-S transition in the cell cycle, as well as p53 tumor suppressor gene in pulmonary proliferative lesions obtained from our previous study were investigated. Over-expression of Cyclin D1 in hyperplasias in rasH2 mice given triple doses was significantly increased, compared to that in the single-injection group, but no significant differences in Cyclin D1 between the single and triple injection groups were observed in hyperplasias in non-Tg mice or lung tumors in either rasH2 or non-Tg mice. There were no differences in the PCNA labeling index of hyperplasias in rasH2 or non-Tg mice between the triple-injection and single-injection groups, while the PCNA labeling index tended to be increased in the tumor, compared with that in hyperplasias. There was neither mutation of p53 nor an increase in immunoreactivity of wild type p53 in these proliferative lesions. These results suggest that cyclin D1 over-expression in alveolar/bronchiolar hyperplasias in rasH2 mice in the triple-injection group is not only indicative of a high cell proliferation rate but also of an important role in the process of malignant transformation.

Beneficial effect of Cyclosporin A on acute hepatic injury induced by galactosamine and lipopolysaccharide in rats

Cyclosporin A (CsA), a potent immunosuppressive agent, is used clinically to prevent allograft rejection after organ transplantation. Although recent experimental studies show that CsA prevents severe hepatic injury associated with tumor necrosis factor-α (TNF-α), the efficacy of CsA has not been confirmed. In the present study, we evaluated whether CsA protects against the severe hepatic injury induced by simultaneous administration of d-galactosamine (GaIN, 200 mg/kg) and lipopolysaccharide (LPS, 10 μg/kg) into the portal vein. The method of CsA (10 mg/kg) was divided into four groups; i.e. preinjection (24 and 2 h before administration of GaIN and LPS), concomitant single-injection, multiple-interval injection (0, 3, 6, 9 and 15 h after administration of GaIN and LPS) and no treatment. In the group receiving multiple-interval injections of CsA, liver function parameters (total bilirubin, asparate aminotransferase and alanine aminotransferase levels in sera) were significantly improved and the development of massive hepatic necrosis was significantly prevented, but no improvement of liver function parameters or histological changes was shown either the pre- or concomitant single-injection groups. The serum levels of TNF-α and interferon-γ showed no differences between the no treatment and multiple-interval injection groups. However, the serum level of interleukin 8 and neutrophil infiltration into the liver tissue after 24 h GaIN and LPS administration were significantly lower than those of the control group. The apoptotic index of liver tissue using the TUNEL method was not significantly different. Our data suggest that CsA protects against acute hepatic injury, if it is administered at the appropriate time during the course of hepatic injury.

Carcinogen dose-dependent variation in the transgene mutation spectrum in urethane-induced lung tumors in transgenic mice carrying the human prototype c-Ha- ras gene

Urethane-induced lung tumors and their genetic changes were investigated in transgenic (Tg) mice carrying a human prototype c-Ha- ras gene (rasH2 mice). Male and female rasH2 mice and non-transgenic (non-Tg) littermates were injected intraperitoneally with 1000 mg/kg of urethane once or three times at 2-day intervals. Hyperplasias and adenomas of the lung were observed in all animals of each group from week 10, and carcinomas were observed in male and female rasH2 mice of the triple injection group from week 10 and female non-Tg mice of the single injection group at 15/20 weeks. The multiplicities of lung proliferative lesions including hyperplasias, adenomas and carcinomas, in treated rasH2 mice were significantly higher than those in treated non-Tg mice. CAG to CTG transversions were observed in the c-Ha- ras gene in these lung proliferative lesions of rasH2 mice of the single injection group at high incidence (male: 58.3%, female: 62.5%), but no mutations of the mouse c-Ki- ras gene were evident in either rasH2 or non-Tg mice. In the triple injection group, transgene mutations were detected at a relatively low incidence, and mouse c-Ki- ras gene mutations(CAA to CGA) were observed in both rasH2 and non-Tg mice. These results suggest that the variation of the lesions induced by different doses of urethane was not the cause of the variation of the mutation spectrum and mutations of both transgene and mouse c-K- ras gene are not principal genetic events in urethane-induced lung proliferative lesions in rasH2 mice.

Repeat bacterial challenge in a subcutaneous chamber model results in augmented tumour necrosis factor-alpha and interferon-gamma response, and suppression of interleukin-10.

The present study compared the effect of a single or a repeat challenge with the Gram-negative pathogen Porphyromonas gingivalis on the local inflammatory response within subcutaneous chamber model in mice. Subcutaneous chambers were implanted 2 weeks prior to the final challenge. The repeat-challenge (REP) group received two intrachamber bacterial injections 14 days apart, while the single-injection group (SIN) received only a single bacterial challenge. Injection of saline was used as the control. The cellular contents of the chamber exudates were used for differential cell counts, and the supernatants were analysed for tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and interleukin (IL)-10 levels. Immunoglobulin G1 (IgG1) and IgG2a levels to P. gingivalis in the exudates were also determined. The results showed that the leucocyte counts increased significantly post-challenge, and the REP group showed the highest number of lymphocytes and neutrophils. Both P. gingivalis-challenged groups exhibited significant increase in TNF-alpha and IL-10 levels at day 1 post-challenge. TNF-alpha levels in the chamber exudate were threefold higher in the REP group compared with the SIN group on day 1 post-challenge (P < 0.05). In contrast, IL-10 levels were significantly lower in the REP group 1 day post-challenge compared with the SIN group. The REP group had significantly higher levels of IFN-gamma at baseline, and this difference remained significant 1 day post-challenge. Analysis of antibody levels to P. gingivalis showed that while the control and the SIN groups had no anti-P. gingivalis IgG in the chamber exudate during the 7-day study period, the REP group showed high anti-P. gingivalis IgG levels. In addition, the titres of IgG2a were fivefold higher than the IgG1 titres. The results showed that a repeat local challenge with P. gingivalis augmented the proinflammatory cytokines TNF-alpha and IFN-gamma, while inhibiting the accumulation of the anti-inflammatory cytokine IL-10. This shift towards a T helper 1 (Th1)-dominant response was reflected in the relatively high anti-P. gingivalis IgG2a titres in the local inflammatory environment 7 days post-challenge.

Effect of Corticosteroids on Brain Growth in Fetal Sheep

In Brief Objective To compare the effects of single and repeated courses of corticosteroids on brain growth in fetal sheep. Methods Pregnant sheep were given intramuscular betamethasone (0.5 mg/kg) at 104 days' gestation followed at 111, 118, and 124 days by equivalent volumes of sterile normal saline (n = 12) or betamethasone (n = 12). Controls received equivalent volumes of sterile normal saline at all four intervals (n = 12). Lambs were delivered at 125 (preterm) or 145 (term) days. After perfusion, we measured weights (grams) for whole brain, cerebrum, cerebellum, and brain stem, volumes (milliliters) for whole brain and cerebrum, and maximum cerebral anterior-posterior length, width, and depth (centimeters). Results In the single-injection group at preterm, there were no significant differences (P = .070) in whole-brain weight between the corticosteroid-treated animals (38.0 ± 1.81 g) and controls (42.5 ± 1.65 g). Cerebral length and depth were significantly reduced in the corticosteroid group (P < .05); other measures were not significantly different. At term, whole-brain weight was significantly lower (47.5 ± 1.70 g; P = .022) compared with controls (53.4 ± 1.73 g). All other measures were significantly reduced (P < .05) except cerebral and brain-stem weights and cerebral length. In the group that received repeated injections at preterm, whole-brain weight was significantly reduced (35.5 ± 1.65 g; P = .005) compared with controls (42.5 ± 1.65 g). All other measures were significantly reduced (P < .05) except cerebellar and brain-stem weights. At term, whole-brain weight was also significantly reduced (42.4 ± 1.52 g; P = .001) compared with controls (53.4 ± 1.73 g) as were all other measures (P < .05). Conclusion Administration of single and repeated courses of corticosteroids to pregnant sheep retarded fetal brain growth. Single or repeated courses of exogenous corticosteroids given to pregnant sheep delay fetal brain growth.

Effect of corticosteroids on brain growth in fetal sheep

Objective: To compare the effects of single and repeated courses of corticosteroids on brain growth in fetal sheep. Methods: Pregnant sheep were given intramuscular betamethasone (0.5 mg/kg) at 104 days’ gestation followed at 111, 118, and 124 days by equivalent volumes of sterile normal saline ( n = 12) or betamethasone ( n = 12). Controls received equivalent volumes of sterile normal saline at all four intervals ( n = 12). Lambs were delivered at 125 (preterm) or 145 (term) days. After perfusion, we measured weights (grams) for whole brain, cerebrum, cerebellum, and brain stem, volumes (milliliters) for whole brain and cerebrum, and maximum cerebral anterior-posterior length, width, and depth (centimeters). Results: In the single-injection group at preterm, there were no significant differences ( P = .070) in whole-brain weight between the corticosteroid-treated animals (38.0 ± 1.81 g) and controls (42.5 ± 1.65 g). Cerebral length and depth were significantly reduced in the corticosteroid group ( P < .05); other measures were not significantly different. At term, whole-brain weight was significantly lower (47.5 ± 1.70 g; P = .022) compared with controls (53.4 ± 1.73 g). All other measures were significantly reduced ( P < .05) except cerebral and brain-stem weights and cerebral length. In the group that received repeated injections at preterm, whole-brain weight was significantly reduced (35.5 ± 1.65 g; P = .005) compared with controls (42.5 ± 1.65 g). All other measures were significantly reduced ( P < .05) except cerebellar and brain-stem weights. At term, whole-brain weight was also significantly reduced (42.4 ± 1.52 g; P = .001) compared with controls (53.4 ± 1.73 g) as were all other measures ( P < .05). Conclusion: Administration of single and repeated courses of corticosteroids to pregnant sheep retarded fetal brain growth.

Assessment of Contrast-enhanced 3D Ultrafast Pulmonary MR Angiography Using Test Injection: Comparison betweenSingle Dose and Double Dose

Purpose : Contrast-enhanced 3-D ultrafast MR angiography is a widely accepted MR imaging technique for theevaluation of the carotid artery, aorta, renal artery, mesenteric artery and portal venous system. To esti-mateitsclinical usefulness, single -and double- dose contrast-enhanced 3-D ultrafast pulmonary MR angiography wasassessed after a timing examination was performed. Materials and Methods : Twenty volunteers underwentgadolinium-enhanced ultrafast pulmonary MR angiog-raphy( 3-D FISP, TR[msec]/TE[msec]=5.0/2.0, withflipangle). In ten volunteers(single-dose injection group) pulmonary MR angiography was performed after theadminstration of 0.1 mmol/kg(single dose injec-tion group), while the other ten(double-dose injection group) eachreceived, prior to angiography, 0.2 mmol/kg. In all cases, a timing examination was performed during axialturbo-FLASH imaging(TR/TE/TI=8.5/4.0/100, flip angle) after injection of the same dose as that used forsubsequent contrast-enhanced pulmonary MR angiography. In both groups, overall image quality, pulmonary arteryvisibility and contrast-to-noise ratio of the pulmonary artery were assessed on the basis of images obtained.Results : With regard to overall image quality, there was no significant statistical difference between the twogroups (P>0.05), and in both, depiction of the central and lobar pulmonary artery was excellent. As regardsdepiction of the segmental artery, the average grading of the single dose injection group was 2.83 ±0.32, that ofthe double dose injection group was 2.85 ±0.3, with no statistical significance(P>0.05). With respect tocon-trast-to-noise ratio of the central, lobar, and segmental arteries, the best results were obtained by thedouble dose injection group(P

Once versus twice daily injections of growth hormone in children with idiopathic short stature

The aim of this study was to compare the growth response of 22 short pre‐pubertal children without growth hormone deficiency, treated with a single daily growth hormone injection (group A), to the growth response of 27 similar children, treated with the same daily dose divided into 2 subcutaneous injections per day (group B), for 1 y, in a randomized study. GH treatment significantly promoted growth parameters, height standard deviation score and height velocity standard deviation score in both groups. Serum insulin‐like growth factor I was also increased. There were no significant differences in growth response, serum IGF‐I levels, or the advance in bone age between the two study groups after 1 y of GH therapy. We conclude that twice daily s.c. growth hormone injections provide no advantages over once daily injection of the same dose in promoting the linear growth of short children without growth hormone deficiency.

Superstimulatory response and oocyte collection in calves

The need to inject FSH twice daily for superstimulation of ovarian follicular development in cattle necessitates frequent attention by farm-personnel and increases the possibility of failures due to mishandling and errors in administration of treatments. A series of three experiments were designed to evaluate the feasibility of superstimulation in beef cattle with a single intramuscular (IM) injection of Folltropin-V diluted in a hyaluronan-based slow-release formulation (SRF). In Experiment 1, cows were assigned to one of three treatment groups to compare two methods of injection as compared to the twice daily IM injection protocol. Superovulatory response of cows (n = 6) treated with twice daily IM injections over 4 days (Control) was greater than of cows treated with a single subcutaneous (SC) injection in SRF (n = 6), while superovulatory response of cows treated with a single IM injection in SRF (n = 6) was intermediate. Experiment 2 was designed to compare two concentrations of SRF (20 mg/mL hyaluronan, 100% compared to 10 mg/mL hyaluronan, 50%) in a single IM injection protocol. The mean number of corpora lutea (CL) were not significantly different (P ≥ 0.05), but the numbers of total ova/embryos (P < 0.05), fertilized ova (P < 0.01) and transferable embryos (P < 0.001) were greater in cows treated with FSH in 100% SRF (n = 20) than cows treated with FSH in 50% SRF (n = 20). Experiment 3 was designed to compare superovulatory response in Red Angus donor cows treated with a single IM injection of Folltropin-V diluted in 100% solution of SRF with those treated with the traditional twice-daily IM injection protocol over 4 days. Mean (±SEM) numbers of CL (13.7 ± 1.2 compared to 13.8 ± 1.2), total ova/embryos (12.3 ± 1.5 compared to 13.7 ± 2.1), fertilized ova (7.2 ± 1.1 compared to 8.4 ± 1.4) and transferable embryos (4.9 ± 0.8 compared to 6.4 ± 1.3) were not significantly different between Control (n = 29) and Single injection (n = 29) groups, respectively. In summary, superstimulation of beef donor cows with a single IM injection of Folltropin-V diluted in 100% solution of SRF resulted in a comparable superovulatory response to the traditional twice-daily IM administration of Folltropin-V diluted in saline over 4 days.

Human peripheral blood lymphocyte-reconstituted, severe combined immunodeficient mice as a model for porcine islet xenograft rejection in humans.

Previously we established human peripheral blood lymphocyte-reconstituted severe combined immunodeficiency (SCID) (hu-PBL-SCID) mice as a model for human islet allograft rejection. The function of xenografted hu-PBL was confirmed to reject human alloislets in hu-PBL-SCID mice. In this study, we modified this model as a porcine islet xenograft to study porcine islet rejection in humans. Chimeric mice were used as the recipients of porcine islets to reveal the mechanisms of xenograft rejection in humans. SCID mice were reconstituted with 30 x 10(6) of hu-PBL initially, and 10 x 10(6) of antihuman CD3-primed PBL was injected intraperitoneally 2 days later as a booster. An additional booster injection provided greater possibility (86.7%, n = 15) of chimera establishment as well as a higher human immunoglobulin concentration in SCID mice than the single injection group. In an in vitro assay, sera from hu-PBL-SCID mice were found to recognize porcine islets by FACS staining. In an in vivo study, immunofluorescent analysis of a frozen section showed that human immunoglobulins adhered to the xenografted porcine islet under the kidney capsule of hu-PBL-SCID mice. Although no mouse immunoglobulins were detected on sections, mouse complement (C3) was shown to adhere to the xenografted porcine islet. Thus, hu-PBL-SCID mice provide a useful model for investigating the real-life situation of porcine islet xenograft rejection in humans.

The effects of exogenous prostaglandins on orthodontic tooth movement in rats

The long-term effects of varying concentrations and frequencies of injectable, exogenous prostaglandin E 2 (PGE 2) on the rate of tooth movement and the amount of root resorption were evaluated. There were 132 male Sprague-Dawley rats 8 weeks old that initially weighed 225 to 250 gm. Five animals were in a pilot study, while seven were baseline controls and eight were appliance controls. The remaining 112 animals were divided into two experimental time periods of 2 and 4 weeks. Then, each experimental time period was divided into four subgroups of 14 animals based on concentration levels of PGE 2 injections, i.e., 0.1, 1.0, 5.0 and 10.0 μg. Half of these animals in the dosage subgroup received a single injection at appliance placement and the other half received weekly injections. A fixed orthodontic appliance consisting of closed-coil nickel-titanium springs were ligated between the maxillary incisors and maxillary first molars. The initial activating force was 60 gm. The results showed that injections of exogenous PGE 2 over an extended period of time in rats did enhance the amount of orthodontic tooth movement. However, there was no statistically significant difference in tooth movement between the single and multiple injection groups or among the four concentration levels of PGE 2 used in either the 2- or 4-week time periods. The amount of root resorption as seen from scanning electron micrographs did increase with the use of prostaglandin injections, specifically with increased numbers of injections and with increased concentrations of PGE 2. (A M J O RTHOD D ENTOFAC O RTHOP 1995;108:380-8.)

Single Versus Staged Epidural Injections of 0.75% Bupivacaine

Epidural anesthesia may be performed as a single injection or by staged doses. Thirty patients undergoing primary total hip replacement were randomly assigned to have epidural anesthesia using a single injection or a staged technique with 25 mL of 0.75% bupivacaine. Arterial plasma bupivacaine concentrations were significantly higher in the single injection group for the first 15 min but were not significantly different thereafter. Peak bupivacaine concentrations did not differ significantly between groups, but the time to achieve the peak concentration was delayed by staging injections (P = 0.001). Hemodynamic effects were similar between groups. Resolution of thoracic sensory block through T12 and duration of motor block measured by Bromage scale were both significantly longer in the staged injection group (P < 0.01). The method of epidural injection may affect resolution of neural block and the time to reach peak arterial plasma concentration of local anesthetic.

Concentrations of passively acquired IgG 1 antibodies in the intestinal lumen of the neonatal calf

Passively acquired specific antibodies in the intestinal lumen are thought to provide protective immunity against infections with rotaviruses and other enteropathogens. In this study, concentrations of functional antibody in the intestinal lumen derived from diet and circulation were measured using 2,4-dinitrophenol (DNP) specific antibody of the IgG 1 isotype, radiolabelled with 125I. The labelled IgG 1 antibody was administered to neonatal calves either orally in the daily milk diet for three consecutive days (Group 1), or by a single intravenous injection (Group 2). After equilibration, the concentrations of protein-bound 125I and the specific DNP binding activities of the labelled protein in the intestinal lumen were measured, and intestinal concentrations of functional IgG 1 were estimated. In Group 1 calves, protein bound 125I concentrations in the pooled small intestinal contents at 2 and 12 h after a milk meal were 50.8±20.5% and 7.9±3.4%, respectively, of the milk concentration. Protein bound 125I concentrations in the small intestinal contents were 0.7±0.4% (mean±SD) of serum concentrations of Group 2 calves, and were similar at 2 and 12 h after a milk meal. For a calf with average serum passive IgG 1 concentrations drinking milk with normal IgG 1 content, these results predict IgG 1 concentrations in the small intestinal contents of milk fed calves at 2 h after a milk meal to be 0.6 mg ml −1, half of which originates from the milk and half from the circulation. At 12 h after a milk meal, intestinal IgG 1 concentrations fall to approximately 0.3 mg ml −1, most of which originates from the circulation. Antibody in the intestinal lumen originating from serum retained more antigen (DNP) binding affinity than that ingested in the milk diet. Therefore, both dietary and circulating IgG 1 contribute significantly to passive IgG 1 antibody concentrations in the small intestinal lumen of neonatal calves, but milk derived IgG 1 antibody concentrations in the small intestinal lumen were not maintained between twice daily feedings.