Boosting social support in caregivers of children with HIV/AIDS

Providing care for a child that is infected with human immunodeficiency virus (HIV) is challenging for the child's caregiver and affects the entire family system. Research has demonstrated that social support has the potential to buffer caregiver stress and facilitate caregiver coping. A two-group experimental study was implemented to test the effect of a social support boosting intervention on caregiver stress, coping and social support among caregivers of children with HIV/acquired immune deficiency syndrome (AIDS). The subjects in the study were caregivers of children with HIV/AIDS. The sample strata included seropositive caregivers (biological parents) and seronegative caregivers (foster parents and extended family members). The measures for the study included the Derogatis Stress Profile, The Family Crisis Oriented Personal Evaluation Scale, and the Tilden Interpersonal Relationship Inventory. These data were then analyzed descriptively and then with a repeated measure MANOVA. Initially, there were no statistically significant differences found between the control and intervention groups. However, when subject HIV status was included in the analysis, the combined dependent variables of stress, coping, and social support were significantly related to the interactions of group by HIV status over time. F values were then computed and no statistically significant differences were found for stress or coping. There were, however, significant differences in measures of social support between groups when adjusting for HIV status of caregivers. In this study, social support levels over time for seronegative caregivers were significantly different from those of seronegative caregivers in the control group. Three case studies are presented that illustrate differences between seronegative and seropositive caregivers. The case studies describe the problems identified by caregivers and the effectiveness of problem solving using the social support boosting intervention. Finally, the mobilization of social support is discussed. Contrasts between the problems of caregivers are made relative to their HIV status. The potential for the effectiveness of the social support boosting intervention is discussed within the context of the caregiver's HIV status.

Clinical spectrum of infantile free sialic acid storage disease

Infantile free sialic acid storage disease (ISSD) is a rare autosomal recessive metabolic disorder caused by a lysosomal membrane transport defect, resulting in accumulation of free sialic acid within lysosomes. Only a few cases have been described. We report on three new cases of ISSD with different modes of presentation: an infant with nephrotic syndrome, a case of fetal and neonatal ascites with heart failure, and a case of fetal ascites with esophageal atresia type III. From these patients and a review of the literature (27 cases total) we draw the following conclusions. 1) "Coarse facies," fair complexion, hepatosplenomegaly, and severe psychomotor retardation are constant findings in this disorder. 2) Nephrotic syndrome occurred in most cases (four in seven) in which renal evaluation was performed. Therefore, ISSD is an important cause of nephrosis in infants with a storage disorder phenotype. 3) Fetal/neonatal ascites or hydrops was the mode of presentation in 13 (60%) of 21 cases. Thus, ISSD enters in the differential diagnosis of hydrops fetalis with a storage disease phenotype. 4) Cardiomegaly was evident in nine cases. 5) Corneae were always clear, and albinoid fundi were reported in five cases. 6) Dysostosis multiplex was not prominent. 7) Bone marrow aspiration could be negative. 8) Death ensued in early infancy with a mean age of 13.1 months. All reported deaths were caused by respiratory infections.

The kidney in children with tyrosinemia: sonographic, CT and biochemical findings

BACKGROUND

Tyrosinemia relates to a deficiency of fumarylacetoacetate hydrolase and presents early in life with central nervous system and liver abnormalities. Renal function is often impaired. Little is known about the architecture and function of the kidneys.

OBJECTIVE

Imaging changes on US and CT are compared to the function of the kidneys in children with tyrosinemia, and followed after liver transplantation.

MATERIALS AND METHODS

Renal sonography, CT and renal function tests in 32 children were reviewed. Renal length, volume, echogenicity and nephrocalcinosis were evaluated. Renal function was assessed by glomerular filtration rate, and the presence of aminoaciduria, acidosis and calciuria. Seventeen children had open renal biopsy during time of liver transplantation. Histology was reviewed. Statistical analyses relating renal structure to function were performed, and repeated after transplantation.

RESULTS

The kidneys were enlarged (47 %), hyperechogenic (47 %) and showed nephrocalcinosis (16 %). There was delayed excretion of contrast medium at CT in 64 %. Aminoaciduria was present in 82 % of children, hypercalciuria in 67 %, tubular acidosis in 59 %, and low GFR in 48 %. Delayed excretion of contrast was associated with low GFR (P < 0.05). Renal biopsies showed dilated tubules (81 %), interstitial fibrosis (56 %), glomerulosclerosis (56 %) and tubular atrophy (56 %). During a mean observation period of 3 years following liver transplantation, GFR improved in 50 %, tubular acidosis in 50 % and hypercalciuria in 70 %. No change was noted in renal size or sonographic architecture.

CONCLUSION

Renal architecture and function are abnormal in the majority of children with tyrosinemia. Liver transplantation improves renal function in about 50 % of patients, but abnormal renal size and architecture persist.

Accuracy of the [13C]-urea breath test in diagnosing Helicobacter pylori gastritis in pediatric patients

BACKGROUND

The causal association between Helicobacter pylori (H. pylori) colonization of the gastric mucosa and gastritis is now well established. Histologic examination of endoscopic biopsy specimens has long been regarded as the gold standard for diagnosis. However, the changes can be focal in nature and presence of the organism may be missed in nonsampled areas. The urea breath test, which uses a stable isotope, offers distinct advantages, in that it is noninvasive and measures the activity of the micro-organism. It thus represents a potentially invaluable tool in the initial diagnosis of the infection and in verifying its eradication.

METHODS

The study design was that of a prospective, blinded comparison of the [13C]-urea breath test with histologic assessment of antral biopsy specimens using the Warthin-Starry stain, to diagnose H. pylori infection in a group of 79 consecutive pediatric patients.

RESULTS

Patients classified as negative by histology (n=67) had breath 13C enrichment of 0.97+/-0.07 delta per thousand (mean+/-SEM), with a range of -0.20 and 2.83 delta per thousand. In contrast, those with a positive histologic results (n=12) had an enrichment of 25.41+/-5.01 delta per thousand (range, 3.43-58.80; p < 0.001). At the chosen cutoff point of 3 delta per thousand, the sensitivity and specificity as well as the positive and negative predictive values of the breath test were uniformly 100%.

CONCLUSION

The [13C]-urea breath test is a highly reliable, noninvasive method for the diagnosis of H. pylori gastritis in children and adolescents.

Biological effects of a neurotoxic pesticide at low concentrations on sea urchin early development. A terathogenic assay

Dose-dependent terathogenic effects of an organophosphate insecticide were found during early sea urchin development. This biological assay is low cost, easy to measure, and allows to detect the effects of the exposure of organisms to the active principle at concentrations lower than the acceptable daily intake (ADI) for man. Effects were found independently from the stage of exposure, and were major as earlier exposure occurred. The stronger effects were exerted on the elongation of the skeletal rods, that was easily measured by following the migration of primary mesenchyme cells, labelled by WGA (wheat germ agglutinin).

[Clinical use of leuprolide acetate depot in a group of gynecologic patients in the preoperative period]

BACKGROUND

The authors examined 33 patients with symptomatic uterine leiomyomas due to undergo total hysterectomy in order to evaluate the effects of treatment with GnRH analogues on leiomyoma and estrogen and progesterone receptors.

METHODS

The patients were divided into two groups: one group was treated with leuprolide acetate (Group A) and the other did not receive treatment (Group B).

RESULTS

A significant reduction in the volume of leiomyomas and estrogen and progesterone receptors was noted in patients in Group A.

CONCLUSIONS

Treatment with GnRH analogues therefore represents a valid aid for patients with uterine leiomyomas and sideropenic anemia awaiting surgery.

A case of non A, non B, non C hepatitis that relapsed into fulminant hepatic failure

We describe a 12 year-old patient that relapsed into fulminant non A, non B, non C (NANBNC) hepatitis 10 weeks post-clinical recovery. A complete clinical and pathological evaluation, including an ultra-structural examination of a liver biopsy was consistent with the diagnosis of NANBNC hepatitis. The patient relapsed into hepatic failure and required transplantation. NANBNC hepatitis may have a relapsing form that can lead to hepatic failure requiring transplantation. Consultants in hepatology should have a high degree of clinical awareness and maintain prolonged patient follow-up.

Multiple primary malignancies in renal cell carcinoma

PURPOSE

We determine the incidence and nature of multiple primary malignancies in patients with renal cell carcinoma, and whether these patients have an increased risk of a second primary malignancy.

MATERIALS AND METHODS

Between July 1989 and January 1997, 551 patients underwent an operation for renal cell carcinoma. The incidence of other primary malignancies was determined and classified as antecedent, synchronous or subsequent. The observed number of subsequent malignancies after diagnosis of renal cell carcinoma was compared to the expected number based on age, race and sex specific 1990 to 1994 incidence rates from the United States Surveillance, Epidemiology and End Results data using the Poisson test.

RESULTS

The number of primary malignancies, including cutaneous malignancies, was at least 1 in 148 patients (26.9%), at least 2 in 34 (6.2%), at least 3 in 6 (1.1%) and 4 in 1 (0.2%). Other malignancies were antecedent in 85 cases (45.0%), synchronous in 74 (39.4%) and subsequent in 30 (16.0%). The most common other primary malignancies were breast, prostate, colorectal and bladder cancer, and non-Hodgkin's lymphoma. Only men with renal cell carcinoma had an increased risk of bladder cancer (standardized incidence ratio 4.3, p = 0.0067).

CONCLUSIONS

Breast, prostate, colorectal and bladder cancer as well as non-Hodgkin's lymphoma were the most common other primary malignancies. Men with renal cell carcinoma have an increased risk of subsequent bladder cancer.

Endocardial fibroelastosis in L-transposition of the great arteries with Ebstein's anomaly: revisited

Ebstein's anomaly is a congenital deformity of the tricuspid valve consisting mainly of leaflet malinsertion. Clinical presentation varies from asymptomatic patients to those with congestive heart failure secondary to significant valvular regurgitation and low right ventricular output. We report here the case of an infant with a diagnosis of corrected transposition of the great arteries and Ebstein's deformity of the left-sided tricuspid valve who developed pulmonary hypertension and endocardial fibroelastosis, two unusual associations with this lesion. We also discuss the pathophysiology of this association and related literature.

Bilateral non-familial renal cell carcinoma

BACKGROUND

Bilateral renal cell carcinoma (RCC) exists in hereditary forms (von Hippel-Lindau disease, hereditary papillary renal cell carcinoma, and hereditary clear cell renal carcinoma) associated with various chromosomal abnormalities, and non-hereditary, apparently sporadic forms. The focus of this study is the clinical description of the latter entity.

METHODS

Synchronous and asynchronous bilateral RCC were identified from a prospective database of 698 consecutive patients undergoing operation for RCC between July 1989 and December 1997 at Memorial Sloan-Kettering Cancer Center. Non-familial RCC was defined as that occurring in those patients without a family or hereditary history of RCC. Patients' records were evaluated for presentation, surgical approach used, and pathology. Actuarial survival from the date of initial operative treatment until the date of last follow-up or death was determined using the Kaplan-Meier method. Comparisons between groups were made using the Mann-Whitney test.

RESULTS

Thirty-three of 698 (4.7%) patients operated for RCC had bilateral disease. Four of the 33 (12.1%) patients had either VHL or documented hereditary RCC, and 29 of 33 (87.9%) had non-familial RCC. Of the 29 patients, histology was conventional (clear cell) in 17 patients, papillary in 5, oncocytoma in 3, and unclassified in 3. One patient had a conventional (clear cell) histology in the first nephrectomy specimen and chromophobe renal cell carcinoma in the second. Partial nephrectomy was used in 100% of patients. Median follow-up time was 52 months. Actuarial 5-year overall survival was 84.5%, and actuarial disease-specific survival was 93.3% at 5 years for the non-familial RCC patients.

CONCLUSIONS

Non-familial bilateral RCC patients represent a distinct subpopulation of renal cancer patients with a good overall prognosis. Partial nephrectomy is an integral part of the surgical management. Although most bilateral tumors present synchronously, asynchronous lesions may occur many years after original nephrectomy, thus committing the patient to long-term follow-up.

Inhibition of cancer cell growth and c-Myc transcriptional activity by a c-Myc helix 1-type peptide fused to an internalization sequence

c-Myc is a nuclear protein with important roles in cell transformation, cell proliferation, and gene transcription. It has been previously shown that a 14-amino acid (aa) modified peptide (H1-S6A,F8A) derived from the helix 1 (H1) carboxylic region of c-Myc can interfere in vitro with specific c-Myc DNA binding. Here, we have linked the above Myc-derived 14-aa peptide to a 16-aa sequence from the third helix of Antennapedia (Int). It has been repeatedly reported that this 16-aa Antennapedia peptide is able to cross mammalian cell membranes and to work as a vector for short peptides. Using fluorescent (dansylated or rhodaminated) peptides, we have shown that the fusion peptide with the Antennapedia fragment (Int-H1-S6A,F8A) but not the c-Myc derived fragment alone (H1-S6A,F8A) was capable of internalization inside MCF-7 human breast cancer cells. Int-H1-S6A,F8A and H1-S6A,F8A were the only two peptides capable of inhibiting coimmunoprecipitation of the c-Myc/Max heterodimer in vitro. We have treated (continuously for 10-11 days) MCF-7 cells with four different peptides: Int, H1-S6A,F8A, Int-H1-S6A,F8A, and Int-H1wt [a peptide differing from Int-H1-S6A,F8A by 2 aa (S6 and F8) in the H1 region]. In intact MCF-7 cells, Int-H1-S6A,F8A was the only active peptide capable of inducing the following biological effects: (a) inhibition of cloning efficiency on plates; (b) inhibition of cell growth and induction of apoptosis in subconfluent/confluent cells; and (c) inhibition of transcription of two c-Myc-regulated genes (ODC and p53). Int-H1-S6A,F8A was active in the 1-10 microM range. Int-H1-S6A,F8A may represent a lead molecule for peptidomimetic compounds that have a similar three-dimensional structure but are more resistant to peptidases and, therefore, suitable for in vivo treatment of experimentally induced tumors.

Priming with tat-deleted caprine arthritis encephalitis virus (CAEV) proviral DNA or live virus protects goats from challenge with pathogenic CAEV

We previously reported that infection of goats with caprine arthritis encephalitis virus (CAEV) tat- proviral DNA or virus results in persistent infection, since the animals seroconverted and direct virus isolation from cultures of blood-derived macrophages was positive. In this study we wanted to determine whether goats injected with CAEV tat- proviral DNA or virus were protected against challenge with the pathogenic homologous virus and to investigate whether CAEV tat- was still pathogenic. All animals injected with CAEV tat- became infected as indicated by seroconversion and virus isolation. Challenge at 8 or 9 months postinfection demonstrated protection in four of four animals injected with CAEV tat- but did not in three of three mock-inoculated challenged goats. Challenge virus was undetectable in the blood macrophages of protected animals during a period of 6 or 10 months postchallenge. In two of four protected animals, however, we were able to detect the challenge wild-type virus by reverse transcriptase PCR on RNA directly extracted from synovial membrane cells surrounding the inoculation site. This result suggests that protection was achieved without complete sterilizing immunity. Animals injected with CAEV tat- and mock challenged developed inflammatory lesions in the joints, although these lesions were not as severe as those in CAEV wild-type-injected goats. These results confirm the dispensable role of Tat in CAEV replication in vivo for the establishment of infection and pathogenesis and demonstrate in another lentivirus infection model the efficacy of live attenuated viruses to induce resistance to superinfection.

Cytogenetic analysis of a parachordoma

We report the cytogenetic and histopathological findings in a 7-year-old female child with an intranasal tumor that is most consistent with a parachordoma. Karyotypic analysis of the tumor revealed clonal numerical and structural chromosome abnormalities. Seven cells displayed recurrent changes: der(2)t(2;4), del(3q), and the loss of chromosomes 9, 10, 20, and 22. Four cells showed a loss of chromosome 17. To the best of our knowledge, these are the first clonal chromosome abnormalities described in parachordoma.

Early prostate cancer detection and potential for surgical cure in men with poorly differentiated tumors

OBJECTIVES

Long-term cure after radical prostatectomy has been reported for men with organ-confined poorly differentiated prostate cancer. However, organ-confined rates have been disappointingly low, ranging from 8% to 18% in earlier series, which have consisted primarily of patients not screened for prostate-specific antigen (PSA). Recently, it has been our impression that a greater number of patients with poorly differentiated tumors have had organ-confined disease than earlier reports would have led us to predict.

METHODS

To test this hypothesis, we reviewed the results of surgical staging in men with poorly differentiated tumors (Gleason score 8 to 10) entered into our prospective data base between August 1992 and June 1996.

RESULTS

Of 109 men undergoing operation during the study period, 64 underwent exploration for planned radical prostatectomy with no previous therapy and comprise the study cohort. In 92%, the initial presentation was an elevated PSA level (median 10.8 ng/mL). We observed an organ-confined rate of 30% and found preoperative PSA levels of 10 ng/mL or less to be a significant predictor of organ-confined disease (45% versus 17%, P = 0.016, chi-square test). On preliminary follow-up (median 31 months), 84% of men with organ-confined tumors are free of PSA relapse, similar to that seen in 233 men with organ-confined moderately differentiated tumors undergoing operation during the study period (P = 0.12, log-rank test).

CONCLUSIONS

Early prostate cancer detection, as reflected by PSA levels of 10 ng/mL or less, is associated with a higher organ-confined rate in men with poorly differentiated tumors. On preliminary follow-up, PSA relapse rates were lower in men with pathologically confirmed, organ-confined, poorly differentiated disease.

Resection of metastatic renal cell carcinoma

PURPOSE

Resection of solitary metastases from renal cell carcinoma (RCC) is associated with a 5-year survival rate of 35% to 50%. Selection criteria are not well defined.

PATIENTS AND METHODS

We retrospectively analyzed our experience with 278 patients with recurrent RCC from 1980 to 1993.

RESULTS

One hundred forty-one of 278 patients underwent a curative metastectomy for their first recurrence (44% 5-year overall survival [OS] rate), 70 patients underwent noncurative surgery (14% 5-year OS rate), and 67 patients were treated nonsurgically (11% 5-year OS rate). Favorable features for survival were a disease-free interval (DFI) greater than 12 months versus 12 months or less (55% v 9% 5-year OS rate; P < .0001), solitary versus multiple sites of metastases (54% v 29% 5-year OS rate; P < .001), and age younger than 60 years (49% v 35% 5-year OS rate; P < .05). Among 94 patients with a solitary metastasis, lung (n = 50; 54% 5-year OS rate) was more favorable than brain (n = 11; 18% 5-year OS rate; P < .05). Survival rates after curative resection of second and third metastases were not different compared with initial metastectomy (46% and 44%, respectively, v 43% 5-year OS rates; P = nonsignificant). Favorable predictors of survival by multivariate analysis included a single site of first recurrence, curative resection of first metastasis, a long DFI, a solitary site of first metastasis, and a metachronous presentation with recurrence.

CONCLUSION

Selected patients with recurrent RCC who can undergo a curative resection of their disease have a good opportunity for long-term survival, particularly those with a single site of recurrence and/or a long DFI.

Inactivation of p53 in a human ovarian cancer cell line increases the sensitivity to paclitaxel by inducing G2/M arrest and apoptosis

Paclitaxel-induced cytotoxicity, cell cycle perturbation, and apoptosis were determined in a human ovarian cancer cell line expressing wt p53 (A2780) and in a subclone (A2780/E6) obtained upon transfection with the product of the E6 gene of the human papilloma virus HPV16. The inactivation of wt p53 in A2780/E6 was verified by measuring the inability of the clone to induce p53 and p21 expression after paclitaxel treatment. The p53-negative clone (A2780/E6) was approximately 50-fold more sensitive to paclitaxel than wt p53-expressing A2780 cells. This increased sensitivity was related to the ability of paclitaxel to induce a strong arrest of cells in the G2/M phase of the cell cycle in A2780/E6 but not in A2780 cells. This different cell cycle arrest was accompanied by increased frequency of paclitaxel-induced p53-independent apoptosis. Initial studies on proteases activation tend to exclude a direct role of ICE and CPP32 in the induction of apoptosis in these cells and show a paclitaxel-dependent increase in FLICE levels, whose biological relevance is however at present not defined.

Maedi-visna virus infection in sheep: a review

The maedi-visna virus (MVV) is classified as a lentivirus of the retroviridae family. The genome of MVV includes three genes: gag, which encodes for group-specific antigens; pol, which encodes for reverse transcriptase, integrase, RNAse H, protease and dUTPase and env, the gene encoding for the surface glycoprotein responsible for receptor binding and entry of the virus into its host cell. In addition, analogous to other lentiviruses, the genome contains genes for regulatory proteins, i.e. vif, rev and tat. The coding regions of the genome are flanked by long terminal repeats (LTR) which play a crucial role in the replication of the viral genome and provide binding sites for cellular transcription factors. The organs targeted by MVV are, in descending order of importance, the lungs, mammary glands, joints and the brain. In these organs, the virus replicates in mature macrophages and induces slowly progressing inflammatory lesions containing B and T lymphocytes. The clinical signs of MVV infection, i.e. dyspnea, loss of weight, mastitis and arthritis, are related to the location of these lesions. Infection with MVV induces the formation of antibodies which can be detected by agar gel immunodiffusion, ELISA and the serum neutralization assay. As neither antiviral treatment nor vaccination is available, diagnostic tests are the backbone of most of the schemes implemented to prevent the spread of MVV. However, since current serological assays are still lacking in sensitivity and specificity, molecular biological methods are being developed permitting the detection of virus in peripheral blood, milk and tissue samples. Future research will have to focus on both the development of new diagnostic tests and a better understanding of the pathogenesis of MVV infection.

Tissue culture methods for the screening and analysis of putative virus-resistant transgenic potato plants

ABSTRACT Following regeneration, putative virus-resistant transgenic plants are usually transferred from tissue culture to a greenhouse or growth chamber to screen for resistance to infection and disease development using mechanical, graft, or insect vector inoculation methods. To reduce initial screening costs and time, we developed mechanical and graft inoculation methods suitable for tissue culture use. The in vitro methods were validated by comparing them with similar greenhouse screens using putative potato virus Y strain o (PVY degrees ) replicase-mediated resistant regenerants of the potato cultivar Atlantic. Five transgenic lines were tested, with similar results obtained from in vitro and greenhouse experiments. Two of the transgenic lines, A1 and A3, showed the greatest resistance to PVY degrees infection, as indicated by low enzyme-linked immunosorbent assay values and infection rates. In vitro mechanical inoculation methods were also used to infect wild-type tomato and tobacco plants with cucumber mosaic virus and potato virus Y. Potato plants were also infected with the phloem-restricted potato leafroll virus, a low-titer virus, using in vitro graft inoculation methods. These results suggest the potential usefulness of these simple, effective, and economical techniques for screening large numbers of putative virus-resistant plants.

[Hypertension in twin pregnancy]

BACKGROUND

An increase of twin pregnancies has been observed during the last ten years and if not correctly treated, they may determine a situation at risk for mother and fetus.

METHODS

The research intends to analyze the results obtained by the observation of 200 twin births in the period between 1991 and 1996 at the Obstetric and Gynaecological Clinic of the University of Rome "La Sapienza". The analysis has been made over a sample, observing the number of women showing arterial hypertension in pregnancy, the possible repercussions on fetus, and the morphological analysis of the placenta.

RESULTS

Eleven women had blood pressure values of 130-90 mmHg (5.5%), albuminuria was not found, [five of them had only hypertension (2.3%) and six had hypertension associated with oedema]. The rate of premature delivery was 66.6%, while rate of term delivery was 66.7%. Delivery was spontaneous in 65% of cases, and caesarean section in 35%. Newborns were classified 80% as AGA (Appropriate for Gestational Age), and 20% as SGA (Small for Gestational Age).

CONCLUSIONS

In personal experience with twin pregnancy, good results have been obtained with an early correction of risk factors (obesity, lower legs swellings, proteinuria), an intensive therapy, rest, cervical cerclage (if incontinent cervix is present), routinely hospitalization during the acute phase of the disease and a careful monitoring. This permitted to treat in time risk subjects, and to avoid gestosis syndrome.

Border disease of sheep and goats

Border disease (BD) is a congenital virus disease of sheep and goats first reported in 1959 from the border region of England and Wales. BD virus (BDV) is a pestivirus in the genus Flaviviridae and is closely related to classical swine fever virus and bovine virus diarrhoea virus (BVDV). Nearly all isolates of BDV are non-cytopathogenic (ncp) in cell culture. There are no defined serotypes but pestiviruses isolated from sheep exhibit considerable antigenic diversity and three distinct antigenic groups have been identified. Distribution of the virus is worldwide. Prevalence rates vary in sheep from 5 to 50% between countries and from region-to-region within countries. The disease in goats is rare and characterized by abortion. Clinical signs in sheep include barren ewes, abortions, stillbirths and the birth of small weak lambs. Affected lambs can show tremor, abnormal body conformation and hairy fleeces (so-called 'hairy-shaker' or 'fuzzy' lambs). Vertical transmission plays an important role in the epidemiology of the disease. Infection of fetuses can result in the birth of persistently infected (PI) lambs. These PI lambs are viraemic, antibody negative and constantly excrete virus. The virus spreads from sheep to sheep with PI animals being the most potent source of infection. Apparently healthy PI sheep resulting from congenital infection can be identified by direct detection of viral antigen or viral RNA in leukocytes or by isolation of ncp virus from blood or serum in laboratory cell cultures. Isolation of virus is unreliable in lambs younger than 2 months old that have received colostral antibody. The isolation of virus from tissues of aborted or stillborn lambs is difficult but tissues from PI sheep contain easily detectable levels of virus. To detect the growth of virus in cell cultures it is essential to use an immune-labelling method. Acute infection is usually subclinical and viraemia is transient and difficult to detect. Sheep may also be infected following close contact with cattle excreting the closely related BVDV.

Endothelial dysfunction in cerebral microcirculation during hypothermic cardiopulmonary bypass in newborn lambs

OBJECTIVES

Inflammatory stimuli or mechanical stresses associated with hypothermic cardiopulmonary bypass could potentially impair cerebrovascular function, resulting in inadequate cerebral perfusion. We hypothesize that hypothermic cardiopulmonary bypass is associated with endothelial or vascular smooth muscle dysfunction and associated cerebral hypoperfusion. Therefore we studied the cerebrovascular response to endothelium-dependent vasodilator, acetylcholine, endothelium-independent nitric oxide donor, sodium nitroprusside, and vasoactive amine, serotonin, in newborn lambs undergoing hypothermic cardiopulmonary bypass (nasopharygeal temperature = 18 degrees C).

METHODS

Studies were performed on 13 newborn lambs equipped with a closed cranial window, allowing for direct visualization of surface pial arterioles. Six animals were studied while undergoing hypothermic cardiopulmonary bypass, whereas seven served as nonbypass, warm (37 degrees C) controls. Pial arteriolar caliber (range = 111 to 316 microm diameter) was monitored using video microscopy.

RESULTS

Topical application of acetylcholine caused a dose-dependent increase in arteriolar diameter in the control group that was absent in animals undergoing hypothermic cardiopulmonary bypass. Hypothermic cardiopulmonary bypass did not alter the vasodilation in response to sodium nitroprusside. Furthermore, the contractile response to serotonin was fully expressed during hypothermic cardiopulmonary bypass.

CONCLUSIONS

The specific loss of acetylcholine-induced vasodilation suggests endothelial cell dysfunction rather than impaired ability of vascular smooth muscle to respond to nitric oxide. It is speculated that loss of endothelium-dependent regulatory factors in the cerebral microcirculation during hypothermic cardiopulmonary bypass may enhance vasoconstriction, and impaired cerebrovascular function may be a basis for associated neurologic injury during or after hypothermic cardiopulmonary bypass.

Results of laparoscopic pelvic lymphadenectomy in patients at high risk for nodal metastases from prostate cancer

BACKGROUND

Laparoscopic pelvic lymphadenectomy (LPLND) can be performed safely and with minimal morbidity in the staging of prostate cancer. Its utility in evaluating patients at high risk for metastatic disease before primarily nonsurgical treatment modalities was evaluated.

METHODS

Twenty-four consecutive patients who underwent LPLND between June 1993 and July 1996 were studied. These patients were considered poor surgical candidates based on several risk factors, as follows: elevation of serum PSA >20 in 19 patients (79%); elevation of serum acid phosphatase in 4 patients (17%); digital rectal examination findings indicative of extraprostatic extension or seminal vesical involvement in 14 patients (58%); and poorly differentiated tumors on prostate biopsy in 19 patients (79%). Nineteen patients (79%) had two or more of these risk factors. Median PSA for the entire series of patients was 35.2 ng/mL (range 7.9 to 133 ng/mL), and median Gleason score was 7 (range 5 to 9). Preoperative CT or MRI was negative for pelvic lymph node metastases in 17 of 23 patients (79%), and bone scan was negative in all 24 patients.

RESULTS

Unilateral (n = 2) or bilateral (n = 22) LPLND was performed in all patients. Six patients (25%) had lymph node metastases detected laparoscopically. Five of the six patients had palpable extraprostatic extension (T3a/b) or invasion of a seminal vesical (T3c), and in four of these patients the site of the metastatic lymph nodes was ipsilateral to the palpable prostate abnormality. None of the risk factors was independently predictive of lymph node metastases within this series of patients. An average of 10.8 +/- 6.5 lymph nodes was removed at a mean operative time of 174 +/- 10 minutes for patients undergoing bilateral LPLND. Estimated blood loss was minimal for 20 of 22 patients (92%) undergoing LPLND alone, and there were no complications requiring open exploration. Mean postoperative hospital stay was 1.2 +/- 0.5 days for patients undergoing LPLND alone.

CONCLUSIONS

LPLND can be used efficiently to identify patients with nodal metastases from select high-risk patients. This, in turn, can exclude such patients from noncurative local and regional therapy.