Environmental enrichment facilitates electric barrier induced heroin abstinence after incubation of craving in male and female rats.

BACKGROUND: Treatment strategies that aim to promote abstinence to heroin use and reduce vulnerability to drug-use resumption are limited in sustainability and long-term efficacy. We have previously shown that environmental enrichment (EE), when implemented after drug self-administration, reduces drug-seeking and promotes abstinence to cocaine and heroin in male rats. Here, we tested the effects of EE on abstinence in an animal conflict model in males and females, and after periods where incubation of craving may occur. METHODS: Male and female rats were trained to self-administer heroin followed by 3 or 21 days of a no-event-interval (NEI). Following NEI, rats were permanently moved to environmental enrichment (EE) or new standard (nEE) housing 3 days prior to resuming self-administration in the presence of an electric barrier adjacent to the drug access lever. Electric barrier current was increased daily until rats ceased self-administration. RESULTS: We found that 21 days of NEI led to significantly greater heroin self-administration and a trend toward shorter latencies to emit the first active lever press in the first abstinence session compared to 3 days of NEI. EE, when compared to nEE, led to longer latencies in the first abstinence session. Also, EE groups of both sexes and in both NEIs achieved abstinence criteria in significantly fewer numbers of sessions. CONCLUSIONS: EE facilitates abstinence in males and females and after periods where incubation of craving may occur. This suggests that EE may benefit individuals attempting to abstain from heroin use and may aid in the development of long term treatment strategies.

Immunohistochemical discrimination of wild-type EGFR from EGFRvIII in fixed tumour specimens using anti-EGFR mAbs ICR9 and ICR10.

BACKGROUND: The human epidermal growth factor receptor (EGFR) is an important therapeutic target in oncology, and three different types of EGFR inhibitors have been approved for the treatment of cancer patients. However, there has been no clear association between the expression levels of EGFR protein in the tumours determined by the FDA-approved EGFR PharmDx kit (Dako) or other standard anti-EGFR antibodies and the response to the EGFR inhibitors. METHOD: In this study, we investigated the potential of our anti-EGFR monoclonal antibodies (mAbs; ICR9, ICR10, ICR16) for immunohistochemical diagnosis of wild-type EGFR and/or the type-III deletion mutant form of EGFR (EGFRvIII) in formalin-fixed, paraffin-embedded human tumour specimens. RESULTS: We found that the anti-EGFR mAb in the EGFR PharmDx kit stained both wild-type and EGFRvIII-expressing cells in formalin-fixed, paraffin-embedded sections. This pattern of EGFR immunostaining was also found with our anti-EGFR mAb ICR16. In contrast, mAbs ICR10 and ICR9 were specific for the wild-type EGFR. CONCLUSION: We conclude that mAbs ICR9 and ICR10 are ideal tools for investigating the expression patterns of wild-type EGFR protein in tumour specimens using immunohistochemistry, and to determine their prognostic significance, as well as predictive value for response to therapy with EGFR antibodies.

The osmotic relationship of the swimbladder nematode Anguillicola crassus with seawater eels.

The study was designed to test the hypothesis that the majority of individuals in a population of Anguillicola crassus can tolerate seawater by osmoconformation with the blood plasma of the eel host. The osmolality of the pseudocoelomic fluid of pre-adult and adult A. crassus was compared to the osmolality of eel plasma after eels were maintained in laboratory freshwater for 2 weeks (short-term transfer) or 3 months (long-term transfer) or in natural seawater for 2 h (acute transfer), 2 weeks or 3 months. The majority of A. crassus (at least 90% of the tested population) osmoconform with their hosts in seawater within +/-30 mOsm/kg of host osmolality. Some pre-adults and adults (15-21% of the total population) were unable to withstand osmotic stress resulting in vacuolation of the hypodermis and intestinal wall, and cuticular detachment. The reasons for variation in the tissue tolerance of A. crassus to increased osmolality of host plasma are unknown and are not related to maturity, sex or conditions in the swimbladder. Osmoconformation in the majority of the population, however, enables parasites to survive and reproduce for long periods in seawater eels. The adaptation of A. crassus to its euryhaline host has played an important part in the rapid spread of the swimbladder nematode in populations of the European eel.

Effect of salinity on hatching, survival and infectivity of Anguillicola crassus (Nematoda: Dracunculoidea) larvae.

The effect of salinity on hatching, larval survival and infectivity of Anguillicola crassus was studied under experimental conditions using eggs obtained from naturally infected eels. Egg hatching rate, second-stage larval survival and larval infectivity were maximal in fresh water and declined with increase in salinity. Larvae survived up to 100 d in fresh water, 70 d in 50 % sea water and 40 d in 100% sea water. Infectivity experiments demonstrated that salinity influenced transmission success throughout the life cycle by decreasing total infectivity of the larval population in utero within female A. crassus and when larvae were free-living in the aquatic environment. Infectivity was age-dependent in relation to salinity. Larvae were infective to intermediate and paratenic hosts for up to 80 d in fresh water, 21 d in 50% sea water and up to 8 d in 100% sea water. The data confirm field observations that infection levels decrease with an increase in salinity. The study contributes to experimental verification of the colonization abilities of A. crassus and supports the hypothesis that A. crassus can be disseminated and transmitted in brackish water. The importance of regular monitoring and stringent hygiene practices in the transportation of eels is emphasized.

Survival and transmission of Anguillicola crassus Kuwahara, Niimi & Itagaki, 1974 (Nematoda) in seawater eels.

The study aims were to quantify the survivorship of Anguillicola crassus in eels in seawater and investigate transmission in estuarine (50% seawater) and marine (100% seawater) simulated conditions. Most A. crassus were able to survive and reproduce in 50% and 100% seawater eels for up to 6 months and therefore could survive during the spawning migration of eels to the Sargasso Sea. Up to 10% of the parasite metapopulation were damaged after long-term exposure to 50% or 100% seawater. Transmission of A. crassus was completed in 50% and 100% seawater in the laboratory, although infection levels in 100% seawater hosts were always lower. Transmission in estuaries is ecologically possible since the copepod Eurytemora affinis is susceptible to infection and is the dominant autochthonous species in most tidal estuaries in the Northern hemisphere. Transmission at sea is unlikely due to lack of suitable intermediate hosts. The data support the suggestion that dissemination of A. crassus has been facilitated by natural movement of eels in coastal waters. It is possible that A. crassus could impair the success of the eel spawning migration to the Sargasso Sea, although there is no direct evidence to support this.

Histopathology of Sanguinicola inermis infection in carp, Cyprinus carpio.

The histopathological response of carp to Sanguinicola inermis was investigated by serial sectioning laboratory infected fish up to 90 days post infection (d p.i.). Juvenile flukes and adults caused mechanical damage to tissues during invasion and migration up to 28 d p.i. Adults partially occluded blood vessels and may have reduced blood circulation. In the initial phase of egg production (28-42 d p.i.), eggs and emigrating miracidia in gill tissue caused breakdown of vascular integrity, necrosis, hyperplasia, haemorrhage and eosinophilic infiltration of epithelial tissue. After 42 d p.i. the host granulomatous inflammatory response encapsulated eggs lodged in the gills, visceral sites and connective tissue displacing normal tissue. Encapsulation and subsequent degradation of eggs and miracidia within granulomata was highly developed by 90 d p.i. Laboratory infections of S. inermis can induce respiratory distress and therefore impair respiration of fish. The parasite also caused pathological changes in osmoregulatory, excretory and haemopoietic tissue and may impair function in these organ systems.

The distribution and host range of species of the blood fluke Sanguinicola in British freshwater fish.

The distribution of host range of Sanguinicola armata, S. inermis and S. volgensis in British freshwater fish are described. S. inermis has been recorded in carp Cyprinus carpio, crucian carp Carassius carassius and tench Tinca tinca in southern, central and eastern England and in koi carp imported from Japan. S. armata has been detected in pike Esox lucius and tench and S. volgensis has been found in chub Leuciscus cephalus, dace Leuciscus leuciscus, perch Perca fluviatilis, roach Rutilus rutilus and pike in southern and eastern England. The first record of the co-occurrence of two species of Sanguinicola (S. inermis and S. volgensis) in a British inland water is reported. The importance of blood flukes and the role of anthropochore movement of fish hosts in dissemination of S. inermis are discussed.

The laboratory maintenance of Sanguinicola inermis Plehn, 1905 (Digenea: Sanguinicolidae).

Methodology is described for the laboratory maintenance of the life-cycle of Sanguinicola inermis, using common carp (Cyprinus carpio) as the definitive host and Lymnaea peregra as the intermediate host. Lymnaea auricularia was also infected but is not considered to be a suitable laboratory host. Tench (Tinca tinca) were susceptible to infection at high cercarial doses but subsequent infection rates were low. Goldfish (Carassius auratus) and Lymnaea stagnalis were refractory to laboratory infection.

Disobliteration of the aorto-iliac (-femoral) arteries with the plaque cracker, using the retroperitoneal approach.

The aorto-iliac disobliteration technique using the LeVeen plaque cracker is described and the results in 70 patients (operated on at the Elisabeth Hospital, Sluiskil, The Netherlands), are presented. The early mortality rate for the series was 4.3%. There were two cases of haemorrhage due to adventitial damage, within two weeks of the operation. The 5 year patency rate was 100%. The LeVeen disobliteration technique is a considerable improvement in the conventional open or half closed endarterectomy. The operation is shorter, and simpler. Also it is ideally suited for combination with the retroperitoneal approach. The technique can be easily combined with disobliterations distal to the groin. The relative advantages and disadvantages of the closed disobliteration and synthetic graft methods are discussed together with the reasons why the closed disobliteration technique seems to be the method of choice in those patients without aneurysms or excessive calcification.

Investigation of possible changes in the detection of cervical carcinoma in patients of Dutch general practitioners.

In a series of 430,015 cervical smears made by general practitioners and coming from all regions of the Netherlands in the period 1972-1980, no significant changes were noted in the rates of positive smears (Papanicolaou IV and V). These data are especially relevant in deciding the age limits for the cytology health service programs. Women aged more than 55 years contribute only 5% of the smears made by house doctors: nevertheless, this group had just as many cases of invasive carcinoma as the younger group. Since 1974 there has been an increase in the diagnosis of adenocarcinoma in situ of the endocervix, probably due to better knowledge of the cytologic and histologic criteria of this lesion. The effects of underdiagnosis of this carcinoma precursor are stressed. It is concluded that it is more important at present to concentrate any additional cytological screening on the "forgotten group" of women aged over 55 years and not yet to extend health survey programs to women under 35 years. However, this policy may need to be reviewed if increased rates of preinvasive tumor in the future lead to an earlier average age for invasive tumor.

The morphogenesis of adenocarcinoma of the cervix-a complex pathological entity.

The cytological and histological features of 20 cases of adenocarcinoma of the cervix are presented of which 14 cases were in situ and two were microinvasive. The frequent association of atypia with malignancies of the cervical squamous epithelium is stressed. Abnormal reserve or stem cells were found in many of these cases. This study demonstrates the importance of the proper identification of these cells in cytological material and gives support to the theory that these cells play a role as a precursor cell to squamous and glandular neoplasms.

Psammoma bodies and some opportunistic infections detected in cervical smears of women fitted with an IUD.

PIP: The incidence of psammoma bodies in cervical smears and of opportunistic infections by actinomyces or ameba is reported in 15,000 patients using IUDs. During the 1972-1978 period, cervical smears from 440,550 women were examined. Of these, 14,980 wore an IUD. 88% of the patients with an IUD were fitted with Multiload Cu250, 8% had Copper T and 4% Lippes Loop. Smears from 7500 patients using oral contraceptives (OCs) and from 7500 patients using no contraception were used as control groups. The smears from the women wearing an IUD were screened and the following were recorded: psammoma bodies, hematoidin crystals, trichomonads, ameba and actinomyces. There were significant differences between IUD users and the control groups in the occurrence of psammoma bodies, ameba and actinomyces but not in trichomonads or hematoidin crystals. Psammoma bodies were found in 1.4% of the cases and actinomyces in 3.7%. Only 1 patient had a transient amebic infestation. The occurrence of psammoma bodies and actinomyces was proportional to duration of IUD use. Most cases were found after 2 years use. The actinomyces were easily identifiable with the Gram stain. The wise course is to make a Gram-stained cervical smear in all women after 2 years of IUD use in order to detect the presence of genital actinomyces.^ieng

A comparison of the efficiency of diagnosis of early cervical carcinoma by general practitioners and cytology screening programs in the Netherlands.

The efficiency of general practitioners and cytology screening programs in the Netherlands in diagnosing neoplasia by means of cervical cytology was investigated. For all age groups of women living in rural or urban areas, the general practitioners were almost twice as successful in detecting cases of cervical neoplasia. No reason could be found why the general practitioners were relatively more successful. The important role of the general practitioner and his or her ability to encourage the high-risk group of women to have early and regular smears is stressed.

A comparison of thiomersal and 50% alcohol as preservatives in urinary cytology.

The efficacy of 50% ethyl alcohol and of thiomersal as preservatives in urinary cytology were compared. In both methods over 80% of the cells were sufficiently well preserved after three days to allow cytomorphological evaluation, and over 50% on the seventh day. In the specimens without preservative, only 54% and 28% were intact after the same time intervals. In contrast with 50% ethyl alchohol, thiomersal is a more effective bactericide, it does not increase the volume of the sample, it is cheaper, and it does not affect the cytomorphology.