A malignant liver cell tumour in a king snake (Lampropeltis getulus)

A neoplastic lesion in the liver of a king snake, Lampropeltis getulus, was identified as a hepatocellular carcinoma. There were metastases in the spleen.     

Fluoro-jade identification of cerebellar granule cell and purkinje cell death in the alpha1A calcium ion channel mutant mouse,leaner

Cell death is a critical component of normal nervous system development; too little or too much results in abnormal development and function of the nervous system. The leaner mouse exhibits excessive, abnormal cerebellar granule cell and Purkinje cell death during postnatal development, which is a consequence of a mutated calcium ion channel subunit, alpha(1A). Previous studies have shown that leaner cerebellar Purkinje cells die in a specific pattern that appears to be influenced by functional and anatomical boundaries of the cerebellum. However, the mechanism of Purkinje cell death and the specific timing of the spatial pattern of cell death remain unclear. By double labeling both leaner and wild-type cerebella with Fluoro-Jade and terminal deoxynucleotide transferase-mediated, deoxyuridine triphosphate nick-end labeling or Fluoro-Jade and tyrosine hydroxylase immunohistochemistry we demonstrated that the relatively new stain, Fluoro-Jade, will label neurons that are dying secondary to a genetic mutation. Then, by staining leaner and wild-type cerebella between postnatal days 20 and 80 with Fluoro-Jade, we were able to show that Purkinje cell death begins at approximately postnatal day 25, peaks in the vermis about postnatal day 40 and in the hemispheres at postnatal day 50 and persists at a low level at postnatal day 80. In addition, we showed that there is a significant difference in the amount of cerebellar Purkinje cell death between rostral and caudal divisions of the leaner cerebellum, and that there is little to no Purkinje cell death in the wild type cerebellum at the ages we examined.This is the first report of the use of Fluoro-Jade to identify dying neurons in a genetic model for neuronal cell death. By using Fluoro-Jade, we have specifically defined the temporospatial pattern of postnatal Purkinje cell death in the leaner mouse. This information can be used to gain insight into the dynamic mechanisms controlling Purkinje cell death in the leaner cerebellum.     

Duration of relapse prevention after cognitive therapy in residual depression: follow-up of controlled trial

BACKGROUND: Although there is good evidence that cognitive therapy (CBT) lessens relapse and recurrence in unipolar depression, the duration of this effect is not known. METHOD: One hundred and fifty-eight subjects, from a randomized controlled trial of CBT plus medication and clinical management versus medication and clinical management alone, were followed 6 years after randomization (4 1/2 years after completion of CBT) and the longitudinal course assessed. RESULTS: Effects in prevention of relapse and recurrence were found to persist, with weakening, and were not fully lost until 3 1/2 years after the end of CBT. Residual symptoms were also lessened. CONCLUSIONS: The effect of CBT in reduction of relapse and recurrence persists for several years. The potential value of subsequent additional CBT some time after cessation should be explored.     

Reproductive adaptations to a large‐brained fetus open a vulnerability to anovulation similar to polycystic ovary syndrome

During the ovarian or menstrual cycle, prior to ovulation, many female primates exhibit a relatively prolonged follicular phase and terminate the postovulatory luteal phase with menstrual bleeding. The prolonged follicular phase is a trait that distinguishes primate from nonprimate species. It enables extended estrogen‐induced proliferation and growth of the uterine endometrium prior to progesterone‐induced maturation during the luteal phase to accommodate a potential pregnancy with a rapidly invading placenta. Progressive development of both an extended duration of estrogen‐induced, preimplantation endometrial proliferation and a rapidly invading placenta across the Primate order may well have been necessary to accommodate differentiation and growth of an increasingly large fetal brain. Prolongation of the follicular phase in primates has also led to the isolation of the final stages of follicle selection (growth deviation of the dominant follicle from its contemporaries) solely within the follicular phase and thus outside the protection of luteal phase progesterone inhibition of pituitary luteinizing hormone (LH) secretion. Such primate reproductive characteristics put the latter stages of ovarian follicle selection at risk of exposure to excessive pituitary secretion of LH. Excessive secretion of LH during follicle selection could result not only in impaired follicle development, excessive ovarian androgen secretion, and ovulation failure, but also in excessive estrogenic stimulation of the uterine endometrium without intervening menstrual periods. Such reproductive abnormalities are all found in a single, prevalent infertility syndrome afflicting women in their reproductive years: polycystic ovary syndrome (PCOS). We propose that successful female reproductive adaptations to accommodate the growth demands of large‐brained primate fetuses have facilitated a particular vulnerability of higher primates to hypergonadotropic disruption of ovulatory function, as found in PCOS. Am. J. Hum. Biol. 15:296–319, 2003. © 2003 Wiley‐Liss.     

Compatibility of lyotropic liquid crystals with viruses and mammalian cells that support the replication of viruses

We report a study that investigates the biocompatibility of materials that form lyotropic liquid crystals (LCs) with viruses and mammalian cells that support the replication of viruses. This study is focused on aqueous solutions of tetradecyldimethyl-amineoxide (C(14)AO) and decanol (D), or disodium cromoglycate (DSCG; C(23)H(14)O(11)Na(2)), which can form optically birefringent, liquid crystalline phases. The influence of these materials on the ability of vesicular stomatitis virus (VSV) to infect human epitheloid cervical carcinoma (HeLa) cells was examined by two approaches. First, VSV was dispersed in aqueous C(14)AO+ D or DSCG, and then HeLa cells were inoculated by contacting the cells with the aqueous C(14)AO + D or DSCG containing VSV. The infectivity of VSV to the HeLa cells was subsequently determined. Second, VSV was incubated in LC phases of either C(14)AO + D or DSCG for 4 h, and the concentration (titer) of infectious virus in the LC was determined by dilution into cell culture medium and subsequent inoculation of HeLa cells. Using these approaches, we found that the LC containing C(14)AO + D caused inactivation of virus as well as cell death. In contrast, we determined that VSV retained its infectivity in the presence of aqueous DSCG, and that greater than 74-82% of the HeLa cells survived contact with aqueous DSCG (depending on concentration of DSCG). Because VSV maintained its function (and we infer structure) in LCs formed from DSCG, we further explored the influence of the virus on the ordering of the LC. Whereas the LC formed from DSCG was uniformly aligned on surfaces prepared from self-assembled monolayers (SAMs) of HS(CH(2))(11)(OCH(2)CH(2))(4)OH on obliquely deposited films of gold in the absence of VSV, the introduction of 10(7)-10(8) infectious virus particles per milliliter caused the LC to assume a non-uniform orientation and a colorful appearance that was readily distinguished from the uniformly aligned LCs. Control experiments using cell lysates with equivalent protein concentrations but no virus did not perturb the uniform alignment of the LC.     

Perinatal decortication impairs performance on an 8-arm radial maze task

Two experiments evaluate the role of the neocortex in rodent spatial learning. In Experiment 1, perinatally decorticated rats and sham-operated controls began ten training sessions at day 200 on an 8-arm radial maze. Decorticated rats made more errors than controls, but showed improvement by the tenth session. In the second experiment, training was extended to determine whether decorticates could eventually match control performance levels if given sufficient training. Spontaneous activity levels were also recorded and compared to maze performance to investigate the relationship between poor performance on the radial maze and activity. More than half of the decorticates reached criterion performance. Decorticates had significantly elevated spontaneous activity levels when compared to controls, and the magnitude of this hyperactivity was related to performance deficits on the radial maze. These results suggest that with extended training decorticates can learn a spatial task. Performance deficits may reflect the hyperactive tendency of decorticates rather than a specific impairment of spatial learning abilities.     

Choice of tests in the biochemical assessment of nephrotoxicity in dogs and rats: A study with maleic acid

Urinalysis represents a useful tool in the evaluation of new pharmaceutical agents acting on the kidney, during preclinical toxcological studies. In the present study, we studied the response of urinary creatinine, LDH, AAP, ALP, β-GAL, GGT, NAG and protein excretion to a single intravenous dose of maleic acid (25 mg/kg for dogs and 100 mg/kg for rats). Enzymes were selected based on their association with renal toxicity and their localisation within the renal tubule. They included lysosomal, brush border and cytosolic enzymes. In male dogs, increases in enzyme excretion occurred within 2 h of maleic acid administration, peaked 3 h after dosing, and returned towards, or to, predose value at 24 h. Marked increases in enzyme levels occurred only for LDH and GGT (10-fold or more). Additionally, there was a marked increase in total protein excretion whereas creatinine excretion decreased. In male rats, the only major difference from control was a higher 0–24 h protein excretion rate (approximately 2-fold). Moderate increases were also present for ALP, GGT and LDH (< 2-fold). In female rats, there was a marked increase in urinary excretion of proteins and LDH, GGT, NAG and ALP (8–13-fold when compared to controls). There were only moderate increases (2-fold or less) in β-GAL and AAP. Creatinine was unaffected by the treatment. Histopathological examination of the kidney revealed moderate to severe proximal tubular necrosis in dogs and minimal to moderate tubular necrosis in rats. Overall, urinary GGT, LDH, total protein and creatinine concentrations are the most sensitive biochemical indicators of maleic acid nephrotoxicity in dogs. For rats, in addition to LDH excretion, total proteins, NAG, GGT and ALP can be considered to be sensitive markers of renal injury. In the light of these results and those reported in literature, it was concluded that the response of urinary markers of nephrotoxicity is heavily dependent on the nephrotoxic agent, the dose, species, sex and study design. Consequently, a range of markers should be examined in order to identify the most useful. Presented at ECCP97, Breda.     

Caudal ventrolateral medullary depressor area controls cerebral circulation via rostral ventrolateral medullary pressor area

The cerebral blood flow (CBF) was determined by radiolabeled microsphere technique in urethane (1.1–1.5 g·kg^–1, i.p.) anesthetized Wistar rats. Microinjection of L-glutamate (1.7 nmol) into the ventrolateral medullary depressor area (VLDA) produced a significant (P<0.01) decrease in CBF from 64±9 (mean ± S.E.M.) to 48±9 ml·min^–1·(100g)^–1 and a significant (P<0.01) increase in cerebrovascular resistance (CVR) from 1.7±0.2 to 2.4±0.4 mmHg per [ml·min^–1(100g)^–1] in the cerebral cortex ipsilateral to the stimulated VLDA side but not in other structures such as brain stem and cerebellum (n=9). Cervical sympathectomy blocked the decrease in CBF and increase in CVR elicited by chemical stimulation of the VLDA (n=10). Depression of the ventrolateral medullary pressor area (VLPA) neurons induced by microinjection of muscimol into the VLPA blocked the CBF decrease and CVR increase following chemical stimulation of the VLDA (n=11). Microinjection of the vehicle solution into the VLDA had no effects on systemic and cerebral circulation (n=7). These results suggest that a vasoconstrictor pathway to control cerebral vessels involves an excitatory projection from the VLDA to the VLPA and the changes in cerebral circulation are mediated by the cervical sympathetic nerves.     

Concurrent cisplatin, infusional fluorouracil, and conventionally fractionated radiation therapy in head and neck cancer: dose-limiting mucosal toxicity

After a preliminary dose-finding study involving 12 patients with advanced or locally recurrent head and neck cancer, 27 patients were treated on a phase II protocol, using fluorouracil 350 mg/m2/d by continuous intravenous (IV) infusion over 5 days, followed on the sixth day by a 2-hour IV infusion of cisplatin 50 mg/m2, administered during the first and fourth weeks of radiation therapy to total doses between 60 and 64 Gy, using 2 Gy daily fractions. Eight of these 27 patients had American Joint Committee on Cancer Staging (AJCC) stage III disease, and 12 had stage IV disease. Four had recurrent disease after surgery. Three-year follow-up is now available. Twenty-one (77.8%) remitted completely following treatment, and 11 remain free of local and regional relapse at 3 years. Four have developed systemic metastases. Following successful salvage treatment in two cases, estimated determinate survival at 3 years is 64%. Acute toxicity was manageable with this regime. Eleven instances of grade 3 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) mucositis were observed, which caused interruptions to radiotherapy in only four cases. No late sequelae have so far been recorded. It is concluded that the protocol described is tolerable but probably did not cause a greater number of locoregional "cures" than would have been expected following conventional radiotherapy alone in this group of patients. The use of infusional fluorouracil with concurrent conventionally fractionated radiation therapy and cisplatin infusion results in mucositis that limits the dose of fluorouracil to levels that are probably subtherapeutic.     

Microplate-based DNA hybridization assays for detection of human retroviral gene sequences.

Nonisotopic, microwell-based DNA hybridization assays for the specific detection of human immunodeficiency virus type 1 (HIV-1) gag, human T-cell lymphotropic virus type I (HTLV-I) pol, and HTLV-II pol DNA sequences were evaluated. The performances of these detection kits (Gene Detective enzyme oligonucleotide assays; Cellular Products, Inc., Buffalo, N.Y.) were assessed by using clinical samples whose infection status were established by amplification by PCR and then liquid hybridization detection by using virus-specific probes. Peripheral blood mononuclear cell lysates from 59 HIV-1-, 35 HTLV-I-, and 19 HTLV-II-infected individuals and from 15 healthy blood donors were used as substrates for PCR amplification. The results of the study demonstrated a clinical sensitivity of 100%. In addition, the enzyme oligonucleotide assays were able to detect 1 to 10 proviral copies subsequent to PCR amplification, indicating an analytical sensitivity comparable to that of liquid hybridization.