In vivo adenovirus-mediated gene transfer into normal and cystic rat kidneys

Gene transfer into the mammalian kidney has proved difficult because of the structural complexity of the organ and its low mitotic index. This article describes the use of intra-arterially injected adenovirus to study gene transfer into the rat kidney in vivo. By pre-chilling the kidney, and incubating the virus with the kidney in the cold for extended periods of time, we were able to successfully transfer a beta-galactosidase (beta-gal) reporter gene into the vasculature without ischemic injury to the kidney. Transfer occurred largely in the cortex when cold was used alone, whereas with the use of cold and vasodilators, transfer was accomplished into the outer medulla in both the inner and outer stripes. In the Han:SPRD rat model of autosomal dominant polycystic kidney disease (ADPKD), gene transfer occurred into the vasculature, some epithelial cysts and interstitial cells. This is the first description of substantial in vivo gene transfer into both normal and cystic kidneys. The methodology could find application in the creation of new models of renal disease, for in vivo therapeutic intervention or for genetic modification of an allograft at the time of harvest.

Ctenocephalides felis flea infestation in horses

The horses were in two stables: in the first stable they were kept together with sheep and in the second stable they were kept together with goats. All horses in both stables were diagnosed as being infested with the cat flea Ctenocephalides felis felis. Foals were severely infested, whereas adult horses were only moderately infested.

Temporal discounting in choice between delayed rewards: the role of age and income

This study examined the effects of age and income temporal discounting (i.e. the decrease in the subjective value of a reward as the delay to its receipt increases). The value of delayed hypothetical monetary rewards was discounted at similar rates by adults of different ages but similar income levels, but at different rates by adults of similar age but different income levels. Specifically, lower income older adults showed a greater degree of temporal discounting than did either upper income older adults or upper income younger adults, but there were no age differences in discounting between the upper income groups. Comparison of these findings with those of a previous study (Green, Fry, & Myerson, 1994) suggests that impulsivity in decision making declines rapidly in young adulthood, reaching stable levels in the 30s. Further, age and income appear to interact in determining the impulsivity of decision making by adults.

The seasonal occurrence of ticks (Acari: Ixodidae) on sheep and in the field in the Judean area of Israel

A 2 year survey of ixodid ticks in the Judean area of Israel between 1983 and 1985 showed that sheep were parasitized by the following species: Rhipicephalus sanguineus group (30.6%), Rhipicephalus bursa (25.3%), Haemaphysalis cretica (20.5%), Haemaphysalis otophila (20.1%) and Hyalomma anatolicum excavatum (3.1%). Three other species, Hyalomma marginatum rufipes, Boophilus annulatus and Amblyomma lepidum were also present but in very low numbers. A total of 50,816 specimens (78.1% adult ticks) were collected from the sheep. In the field, a total of 4780 ticks (8.7% adults) were collected and 64.3% consisted of R. bursa. Other species found were H. cretica (14.5%), H. a. excavatum (13.7%), H. otophila (3.4%), R. sanguineus group (1.9%) and 1.7% was Ixodes eldaricus. The number of ticks collected varied from year to year and seasonal activity was observed in all species except for H. a. excavatum. In all species, males outnumbered females, with the exception of H. cretica. The seasonal occurrence, tick ecology and disease relationship is discussed for each species.

Sarcoptic mange in wild ruminants in zoological gardens in Israel

Sarcoptic mange (Sarcoptes scabiei) occurred among wild ruminant species in five zoological gardens in Israel, from 1984 to 1994. Infestation of five ruminants by S. scabiei is reported for the first time: mountain gazelles (Gazella gazella), Nubian ibexes (Capra ibex nubiana), a barbary sheep (Ammotragus lervia), elands (Taurotragus oryx), and an Arabian oryx (Oryx leucoryx). All animals in the herds were administered ivermectin orally at a dose of 200 micrograms/kg body weight daily for 3 consecutive days. This was repeated three times at 2-wk intervals. The disease was eradicated in four small zoos, whereas in the biggest zoo, only control was achieved. Mortality among animals < 4 mo and > 8-yr-old animals composed 65% of mortality among all age classes.

COSAS 2.0--a Macintosh-based stereological analysis system

Quantitation of morphological data is a component of both basic and clinical research. Often it is necessary to extract three-dimensional information from two-dimensional images. Stereological analysis, the most reliable means of achieving this, is also increasingly used as a diagnostic tool in pathology. COSAS, a COmputerized Stereological Analysis System, is software which allows rapid recording of morphological data from two-dimensional images and performance of analyses necessary for both quantitation and three-dimensional interpretation. COSAS is reliable and easy to use. It was previously available in a VAX-based version (Cornacchia and Black, 1988). An improved version, COSAS 2.0, is now available for use on the Macintosh. COSAS 2.0 is considerably more "user friendly" and flexible than the VAX version of the program. COSAS 2.0 eliminates the necessity for the user to be linked with a large computer. COSAS 2.0 has the ability to interface with other commercially available software for scanned images (e.g., Adobe Photoshop, NIH-Image) and data manipulation (e.g., EXCEL, Delta Graphics). These features make it useful to both research and clinical laboratories. Although designed for the biologist, the system may be used to study cross sections of any solid. It could be of interest to material scientists, petrographers, and ceramicists, all of whom need to obtain quantitative information about three-dimensional spatial organization from two-dimensional sections or projections.

A study of an enzootic focus of sheep babesiosis (Babesia ovis, Babes, 1892)

Morbidity and mortality due to Babesia ovis in sheep flocks grazing in an enzootic area of Israel occur yearly, about 2 weeks after detection of adult Rhipicephalus bursa ticks on the animals. Disease incidence peaks in May, but lasts throughout the active period of the adult ticks in the spring-summer months of April-July. No clinical cases of babesiosis have been registered during the active period of the preimaginal stages of R. bursa, from October to February. Incidence of parasitaemia during the spring-summer months was variable, ranging between 2 and 25%. However, in the winter months the incidence of parasitaemia in hoggets increased considerably, reaching 4-60% of the animals. A positive serological response to B. ovis was found in 84.5% of the hoggets and 88.9% of the ewes. In ewes, the prevalence of the serological response showed no marked seasonal variations. Colostral sera of 67.5% and 75% of the ewes and hoggets, respectively, were serologically positive for B. ovis. No antibodies were detected in the sera of lambs less than 3-4 months of age. The epizootiology of sheep babesiosis appears to differ from that of bovine babesiosis.

FK506 nephrotoxicity: morphologic and physiologic characterization of a rat model

BACKGROUND

FK506 is a useful agent in the prevention of allograft rejection but has recently been shown to be nephrotoxic.

EXPERIMENTAL DESIGN

Sprague-Dawley rats (n = 40) were divided into four groups: control (C); low-salt (LS); FK506, 3 mg/kg daily by gavage (FK); and FK506-low-salt (FK-LS). After 6 weeks, the animals underwent physiologic studies and were sacrificed with perfusion fixation of the kidneys. Semiquantitative analysis of morphologic injury was performed as well as grading of juxtaglomerular apparatus (JGA) granularity (1-micron plastic sections). Computer-assisted morphometry was used to measure medullary thick ascending limb (mTAL) size within the inner stripe.

RESULTS

Serum creatinine and plasma renin activity were significantly elevated only in the FK-LS group, but both FK groups had significantly increased fractional excretion of Mg. Tubular atrophy and fibrosis involving medullary rays and inner stripe (areas of low oxygen availability) was minimally present in FK, but prominent in FK-LS (P < 0.001). Injury correlated with decreased function (P < 0.001). Variance of mTAL size, an expression of co-existent tubular atrophy and hypertrophy was significantly greater in FK-LS and correlated with decreased renal function and urine osmolality (P < 0.001). JGA granularity was increased by FK506 (P < 0.006) with the highest values in FK-LS (P < 0.001), and strongly correlated with injury (P < 0.001). JGA granularity did not correlate with circulating renin activity levels, suggesting local activation of a renin-angiotensin system.

CONCLUSIONS

FK506 compromises renal parenchymal zones which are known to have limited oxygen availability (medullary ray and inner stripe), a pattern that has been observed with other nephrotoxins. The injury is potentiated by salt depletion and may be mediated by the renin-angiotensin system. Furthermore, these findings illustrate the close correlation between the medullary injury that was observed and the impaired function that was documented.

Vascular permeability factor (vascular endothelial growth factor) is strongly expressed in the normal male genital tract and is present in substantial quantities in semen

PURPOSE

Vascular permeability factor (VPF) is a potent inducer of microvascular hyperpermeability and stimulates endothelial cell growth and angiogenesis. This study examines expression of VPF in the male genital tract.

MATERIALS AND METHODS

Vascular permeability factor in seminal plasma was quantified by immunoassay. Vascular permeability factor mRNA and protein expression in tissue were studied by situ hybridization and immunohistochemistry.

RESULTS

All seminal plasmas studied contained high levels of VPF. Prostatic and seminal vesicle epithelium labeled strongly for VPF mRNA and protein.

CONCLUSIONS

The strong expression of VPF in prostate and seminal vesicle and the high concentration of VPF in semen suggest an important role for this cytokine in male fertility.

Infections complicating tunneled intraspinal catheter systems used to treat chronic pain

Tunneled intraspinal catheters and catheter-pump systems are increasingly common treatments for severe chronic pain, but these long-term catheters have caused meningitis, epidural abscesses, and other serious infections. At a cancer referral center, 81 catheters were placed in 72 patients over a 7-year period. There were seven catheter-associated infections: two were meningeal (one was accompanied by an epidural abscess and one by a pocket infection and bacteremia), four were associated with a pocket, and one was associated with a tunnel. The infection rate was 0.77 per 1,000 catheter-days. Pathogenic organisms that were isolated were primarily normal skin flora. By multivariate Cox analysis, the only factor significantly associated with catheter infection was prolonged catheter placement surgery, i.e., a procedure lasting at least 100 minutes (RR, 8.8; 95% CI, 1.6-50). Three patients were cured by removal of the catheter and treatment with antibiotics, and symptoms were satisfactorily suppressed in four patients with antibiotics alone. Considering the severity of illness in catheter recipients, the infection rate was relatively low. Removal of the catheter does not appear mandatory when the goal is suppression of infection-related symptoms, especially when the infection has not spread to the CNS, the infecting organism has an intrinsically low virulence, and the infected patient is terminally ill.

Nine members of the myomodulin family of peptide cotransmitters at the B16-ARC neuromuscular junction of Aplysia

1. Neuromodulation by multiple related peptides with different spectra of physiological effects appears an effective way to integrate complex physiological functions. A good opportunity to examine this issue occurs in the accessory radula closer (ARC) neuromuscular circuit of Aplysia, where, extensive previous work has shown, acetylcholine-induced contractions of the muscle are variously modulated by several families of peptide cotransmitters released under appropriate behavioral circumstances from the muscle's own two motor neurons. 2. In this work we focused on the myomodulins (MMs) released from motor neuron B16. Previous work has characterized MMA (PMSMLRLamide) and MMB (GSYRMMRLamide). We now similarly purified from ARC neuromuscular material and sequenced MMC (GWSMLRLamide), MMD (GLSMLRLamide), MME (GLQMLRLamide), and MMF (SLNMLRLamide). Three additional MMs, MMG (TLSMLRLamide), MMH (GLHMLRLamide), and MMI (SLSMLRLamide), are encoded by a known MM gene. B16 probably synthesizes, and coreleases, all nine MMs. Further MMs have been found in other mollusks. All evidence indicates that the MMs are a major, widely distributed family of molluscan neuropeptides important as neuromuscular modulators and probably also central transmitters or modulators. 3. MM effects on motor neuron B16-elicited ARC muscle contractions were best analyzed as the sum of three distinct actions: potentiation, depression of the amplitude of the contractions, and acceleration of their relaxation rate. We compared the effectiveness of all nine MMs in these respects. We correlated this with their effectiveness in enhancing the L-type Ca current and activating a specific K current in voltage-clamped dissociated ARC muscle fibers, effects we previously proposed to underlie, respectively, the potentiation and the depression of contractions. 4. All nine MMs were similarly effective in enhancing the Ca current and, as far as it was possible to determine, potentiating the amplitude as well as accelerating the relaxation rate of the contractions. 5. In contrast, the MMs' ability to activate the K current and depress the contractions varied greatly. MMB and MMC, in particular, were weak, whereas the other seven MMs were considerably more effective in both respects. 6. Altogether, we were able to explain the potentiating and depressing strengths of the MMs by the magnitude of their modulation of the Ca and K currents, providing further support for our hypothesis that the effects on contraction amplitude are mediated by the effects on the two currents. 7. The net effect on contraction amplitude was determined by the balance between the potentiation and depression. Although most MM concentrations had both potentiating and depressing actions, potentiated contractions predominated at low and depressed contractions (but with accelerated relaxation rate) at high concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)

Level of functioning, severity of illness, and smoking status among chronic psychiatric patients

It was hypothesized that chronic psychiatric patients who had quit smoking would be more functional and have lower Brief Psychiatric Rating Scale (BPRS) scores than those who continued to smoke. We interviewed 300 chronic psychiatric patients followed in the community. Fourteen percent were former smokers and nearly 11% had never smoked. Fifty-six percent of the sample were current smokers who had no intention of quitting, 13% were considering quitting, and 6% were seriously preparing to quit or had actually quit for a short period. When compared with current smokers, former smokers were more likely to live independently (p < .026) and less likely to have a drug or alcohol problem (p < .013). A random sample of current smokers were compared with former smokers on the BPRS. Former smokers had lower total BPRS scores (p < .03), and lower withdrawal/retardation subscale scores (p < .0058) than current smokers. We concluded that better functioning patients who smoked would be more likely to quit.

Induction of heat-shock proteins does not prevent renal tubular injury following ischemia

The possible protective effect of heat-shock proteins (HSPs) on ischemic injury to renal cells was assessed in two different experimental models: ischemia-reflow in intact rats and medullary hypoxic injury as seen in the isolated perfused rat kidney. Heat shock was induced by raising the core temperature of rats to 42 degrees C for 15 minutes. Following this, Northern blots showed enhanced gene expression of HSP70, HSP60 and ubiquitin at one hour and reaching a maximum by six hours after heat shock in all regions of the kidney, but most prominently in medulla and papilla. The HSP70 protein in the kidney, estimated by immunohistochemical means, was detectable 24 hours following heat shock and further increased at 48 hours following heat shock. In the first set of experiments, the animals underwent uninephrectomy followed by cross clamping of the remaining renal artery for 40 minutes prior to reflow. Serum creatinine and urea nitrogen rose to 3.15 +/- 0.98 and 126.4 +/- 62.5 mg/dl at 24 hours. No significant differences were observed at 24, 48 and 72 hours after reflow between these values in control rats and rats pretreated with heat shock 48 hours earlier. Severe morphological damage to proximal tubules of the renal cortex was observed to the same extent in both groups. In a second set of experiments, the right kidney was removed either 24 or 48 hours after heat shock and perfused in isolation for 90 minutes. Functional and morphological parameters were compared with those of isolated perfused kidneys obtained from animals that had not been subjected to heat shock.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid DNA fragmentation from hypoxia along the thick ascending limb of rat kidneys

Extensive DNA fragmentation, a marker for programmed cell death, was selectively and rapidly induced by hypoxia in the thick ascending limbs of rat kidneys. In isolated perfused kidneys, DNA breaks were present in medullary tubules as early as after 10 minutes of local hypoxia and were prevented by reduction of metabolic work. In a model of radiocontrast-induced acute renal failure, DNA breaks were detected selectively along thick ascending limbs as early as 15 minutes following insult, preceding overt morphological damage. Hypoxia induces rapid DNA fragmentation along thick ascending limbs, where programmed cell death could play an important role in nephron injury and kidney failure.

Nondysplastic fetal renal hypoplasia associated with severe oligohydramnios: clinical, pathologic, and morphometric findings

Two fetuses with severe bilateral renal hypoplasia are described; both diagnoses were made following elective abortion for oligohydramnios and suspected renal dysplasia. A 20-week female fetus (46,XX) had pulmonary hypoplasia and very small kidneys (7% of expected weight) that were normally shaped and nondysplastic, with well-formed medullae and metanephric blastema and markedly diminished cortices with only rare glomeruli. A 23-week male fetus (46,XY) had small kidneys (13% of expected weight) that were nondysplastic, normally shaped, and histologically well organized with moderately decreased numbers of glomeruli. Isolated bilateral renal hypoplasia has not previously been well characterized in fetuses; the presence of oligohydramnios (both cases) and pulmonary hypoplasia (one case) suggests that this finding is associated with impaired fetal renal function and may adversely influence neonatal survival.

Non-nephrotic children with membranoproliferative glomerulonephritis: are steroids indicated?

Alternate-day steroids are currently recommended to treat children with membranoproliferative glomerulonephritis (MPGN). This recommendation is based largely on uncontrolled studies demonstrating improved renal survival with steroid therapy. We reviewed the outcome of 39 children who presented with MPGN between 1968 and 1990; 27 children were treated with steroids and 12 children received no drug therapy. Life-table analysis comparing renal survival of treated versus untreated children demonstrated no difference by log rank analysis. Treated and untreated groups were compared on the basis of nine features at presentation: age, sex, type of MPGN, presence and type of hematuria, hypocomplementemia renal insufficiency, hypertension, and nephrosis. Treated children were likely to be female (P < 0.01) and nephrotic (P < 0.02). Actuarial survival analyses were performed comparing the nine features with renal survival through 10 years of follow-up. Normotensive (P < 0.025) and non-nephrotic (P < 0.05) children had improved renal survival. The 11 non-nephrotic children demonstrated 100% long-term renal survival, including 7 who received no steroid therapy. At last follow-up, all non-nephrotic children had normal renal function, serum albumin levels > 3 g/dl, and were normotensive. These data suggest that non-nephrotic children with MPGN may forego steroid treatment without compromising long-term renal function. The current common practice of treating all children with MPGN with steroids should be re-examined.

Biosensors: where do we go from here?

In the 1980s, researchers predicted that biosensors would dominate hospital POC, POL, and home testing. While that hasn't quite come to pass, here's what biosensors have accomplished and a look at their future.

Tumefactions as an extravascular manifestation of Wegener's granulomatosis

Wegener's granulomatosis appeared as localized or infiltrative tumefactions in six patients. The tissue swellings affected the retroperitoneum, mediastinum (two), breast, retroorbital tissue (two), and gingiva. There was extensive fibroblastic proliferation in each case with a predominantly granulocytic inflammatory component, microabscess formation, and collagen necrobiosis. In one of the mediastinal lesions and in the gingiva, there was a granulomatous component as well. In the breast were scattered multinucleated histiocytes. Necrotizing vasculitis was absent or limited in all cases. All patients responded dramatically to cyclophosphamide and/or prednisone after the diagnosis was established. These observations indicate a role for tissue destruction in Wegener's granulomatosis mediated by granulocytes without a vasculitic component.

FRF peptides in the ARC neuromuscular system of Aplysia: purification and physiological actions

1. One preparation that has proven to be advantageous for the study of neuromuscular modulation is the accessory radula closer (ARC) muscle of Aplysia californica and its motor neurons B15 and B16. In this study three members of a new peptide family have been purified from this well-characterized preparation. Because these peptides terminate in Phe-Arg-Phe-amide, we have named them FRFA, FRFB, and FRFC. The FRFs are thus RFamide peptides and are related to the widely studied neuropeptide FMRFamide. 2. The FRFs are present in the ARC motor neuron B15 in small quantities. 3. When they are exogenously applied, the FRFs decrease the size of ARC muscle contractions elicited by stimulation of either motor neuron B15 or B16. They appear to do this by a combination of presynaptic and postsynaptic actions. 4. Presynaptically, the FRFs appear to act like the buccalins, another family of inhibitory ARC neuropeptides. Both families of peptides reduce the size of motor neuron-elicited excitatory junction potentials (EJPs) presumably by decreasing presynaptic acetylcholine (ACh) release. 5. Postsynaptically, the FRFs appear to depress contractions because they activate a characteristic voltage-dependent, 4-amino-pyridine-sensitive K current in the ARC muscle. The same current is activated by a second class of ARC modulators: those that exert potentiating actions at low doses and inhibitory actions at high doses, i.e., serotonin, the small cardioactive peptides (SCPs), and particularly the myomodulins. Receptors mediating activation of the K current by the FRFs and the other modulators do, however, appear to be different. 6. We hypothesize that the inhibitory actions of the FRFs prevent excessively large muscle contractions. If contraction size is limited, then contraction duration is also limited. This may allow faster and more energetically favorable switching between contractions of antagonistic muscles.