Cationic antiprotozoal drugs. Trypanocidal activity of 2-(4'-formylphenyl)imidazo[1,2-a]pyridinium guanylhydrazones and related derivatives of quaternary heteroaromatic compounds.

A series of quaternary 2-phenylimidazo[1,2-a]pyridinum salts has been prepared and evaluated for antiparasitic activity. Primary attention was focused on derivatives with amido, substituted hydrazone, and heterocyclic functionality at the para position of the phenyl substituent. Guanylhydrazones and N-substituted guanylhydrazones of the 4'-formyl-substituted compounds are very active against the blood state Trypanosoma rhodesiense in mice by subcutaneous or oral administration. The most potent compounds attain 100% survival for 30 days at doses of less than 1.0 mg/kg (sc) and greater than 5.0 mg/kg (po). Weaker activity is noted for certain other 4'-substituents such as carboxamidines and carboxamide oximes. Considerable variation in structure, including replacing of the imidazo [1,2-a]pyridinium ring by other cationic heterocyclic rings and insertion of linking groups between the heterocyclic ring and phenyl group, can be done, and a high level of activity is maintained. Relationships between these structural changes and biological activity are discussed.

Cost effectiveness of routine postmortem histology.

In a retrospective study of the records of 160 necropsies it was found that, according to the clinical and gross necropsy findings, no clinically important abnormality would have been anticipated in 46% of the tissue samples. The estimated annual cost of processing this material alone was pounds 10,500, including the salary of one full time medical laboratory scientific officer (MLSO). Few of the microscopic findings led to a change in diagnosis. It is suggested that unselected postmortem histology is, for diagnostic purposes, not cost effective.

Immunolocalization of cathepsin D in normal and neoplastic human tissues.

The aspartic proteinase cathepsin D was purified from human spleen and localised in various formalin fixed paraffin embedded human tissues using the peroxidase-antiperoxidase (PAP) technique. Cathepsin D was shown not only in macrophages but also in other connective tissue cells, and in epithelium. It was present in spleen (littoral cells and cells within Malpighian bodies), liver (hepatocytes and Kupffer cells), lung (alveolar macrophages and bronchial epithelium), brain (neurones), lymph nodes (histiocytes in germinal centres, sinusoid lining cells) and stomach (parietal and mucous neck cells). Cathepsin D was also found in carcinomas of bronchus, stomach, colon, kidney, breast, ovary, bladder and pancreas, both in neoplastic epithelium and in stromal cells, but was seldom present in connective tissue neoplasms. A group of malignant lymphomas also contained the enzyme within scattered cells. The distribution of cathepsin D seems to be much wider than that of the structurally related aspartic proteinases pepsin, gastricsin, and renin.

Pepsinogen in gastric carcinoma cells.

Immunoperoxidase staining of 125 gastric carcinomas showed pepsinogen in tumour cells of seven (5.6%) cases. Carcinomas from other sites were negative. The phenomenon is probably too uncommon to be useful in identifying secondary carcinomas as gastric in origin, but it is of some biological interest.

Gastricsin in the benign and malignant prostate.

An immunoperoxidase (peroxidase-antiperoxidase) method was used to localise the gastric acid proteinase gastricsin in prostate. The enzyme was present, probably as zymogen, in acinar lining cells in 66 (69%) of 96 cases of benign prostatic enlargement; other normal tissues from male genital tract were negative. It was also present in the tumour cells in 21 (39%) of 54 cases of prostatic adenocarcinoma. The findings support the suggestion that the prostate is the source of the gastricsin of normal seminal fluid. It is not yet clear whether its presence in prostatic carcinomas will be of diagnostic use.

Combined proliferating cell nuclear antigen and morphometric analysis in the diagnosis of cutaneous lymphoid infiltrates.

AIMS: To evaluate the use of morphometry in the diagnosis of benign and malignant cutaneous lymphoid infiltrates; and to determine whether the sensitivity of detection of cutaneous T cell lymphoma (CTCL) could be improved by selectively measuring cells expressing proliferating cell nuclear antigen (PCNA). METHODS: 44 archival biopsy specimens were studied. These included cases of CTCL, non-specific chronic dermatitis, lichen planus and lupus erythematosus. PCNA was identified using a standard immunohistological technique. Reactive cells were identified using automatic colour discrimination, and the size and shape were determined interactively. Similar measurements were made on the total dermal lymphocyte population. RESULTS: There was no significant difference between the proportions of PCNA reactive cells in any of the diseases studied. The PCNA positive lymphocytes in CTCL were larger than those in lupus erythematosus and lichen planus and were more irregular in shape than those in chronic dermatitis. Differences were also seen in the total lymphocyte population. Plotting cell size and shape(fcircle) for PCNA cells together allowed CTCL to be differentiated from the inflammatory disorders with a sensitivity of 80% and a specificity of 93%. This was better than could be achieved using measurements made on the total cell population. CONCLUSIONS: This technique can be partly automated and could be useful in the differential diagnosis of cutaneous lymphoid infiltrates. The result are also of some interest in the further understanding of patterns of cell proliferation in skin associated lymphoid tissue.

Necropsy study of mountaineering accidents in Scotland.

One hundred and twenty one people died in mountaineering accidents in Scotland between July 1978 and December 1983. Necropsies were carried out on 42, which form the basis of this report. In 21 cases head injury was major fatality factor, but in 11 of these there were also serious chest injuries. Focal brain damage (haematomas, contusions, or lacerations) was more common (n = 21) than diffuse brain damage (n = 18). Over half of the victims with severe head injury had few other injuries and would probably have survived had the head injury been prevented. Spinal injuries usually occurred with other major injuries. Chest injuries were common, being serious in 18 cases, but abdominal injuries were uncommon. Four climbers with only minor injuries died of hypothermia.

Effect of using templates on the information included in histopathology reports on specimens of uterine cervix taken by loop excision of the transformation zone.

AIM: To determine the change in information relayed from histopathologists to clinicians by using templates for reporting specimens of uterine cervix sampled by loop excision of the transformation zone (LETZ). METHODS: Minimum datasets for the information required from LETZ specimens received from the colposcopy clinic, Royal Infirmary, Edinburgh, were incorporated into templates on the clinical service computer (Pinnacle) of the pathology department, University of Edinburgh. Pathologists completed hard copy versions, which were transcribed into the computer templates for report generation. The effect of the changes on the quality of the pathology reports was studied. The number of cases in which each item in the dataset received comment in template generated reports was compared with that in traditional prose reports compiled before the use of the templates and in prose reports issued after the introduction of the templates. Questionnaire studies were undertaken of clinicians' and pathologists' opinions of the template reports. RESULTS: In the template reports nearly all items received comment in almost 100% of cases. In the prose reports issued both before and after the templates were in use, most items were mentioned in a significantly lower proportion of cases. Clinicians thought the template reports were clearer and the information could be more readily assimilated than from the prose versions. CONCLUSIONS: The use of template reports in these types of specimen allowed more consistent and detailed information transfer. The change appeared to result from the use of the templates rather than from increased awareness of the items to be reported.

Localisation of embryonic prealbumin in formalin-fixed human fetal and adult tissue.

The presence of embryonic prealbumin (EPA) has been confirmed in fetal fibroblasts, chondrocytes, and distal tubular epithelial cells by an indirect immunoperoxidase technique. EPA has often been found also in the stromal cells of benign and malignant mesodermal tumours, but not in the epithelial cells of benign and malignant epithelial tumours. That EPA is not an exclusive product of neoplastic mesodermal cells is demonstrated by our finding of EPA in fibroblasts of granulation tissue, irradiated fibroblasts, and in distal tubular epithelial cells of miscellaneous adult kidneys.

The activity of a benzothiopyranoindazole (IA-4 N-oxide) against Schistosoma mansoni infection in rhesus monkeys.

The prophylactic and therapeutic efficacies of IA-4 N-oxide against Schistosoma mansoni in rhesus monkeys (Macaca mulatta) have been evaluated. Ten monkeys were divided into 5 groups of 2 monkeys each. All monkeys were exposed to S. mansoni cercariae on day 0 and treatment groups were established as follows: untreated controls, oral prophylactic administration, intramuscular prophylactic administration, oral therapeutic administration, and intramuscular therapeutic administration. Analysis of parasitologic and pathologic criteria indicate that the compound is most effective when administered as a therapeutic regimen. Complete cures were effected in these monkeys. Prophylactic treatments resulted in a delay in onset of patency and reductions in fecal egg excretion, worm burdens, and tissue damage.

The immunologic modulation of morbidity in schistosomiasis. Studies in athymic mice and in vitro granuloma formation.

These studies were designated to test the hypothesis that granulomatous hypersensitivity associated with schistosomiasis, its modulation, and subsequent morbidity are contingent on thymic-dependent lymphocyte function. Studies in athymic mice were integrated with in vitro studies on granuloma formation. Athymic animals tolerate low levels of infection well but are increasingly susceptible to morbidity as the challenge burden increases or becomes associated with simultaneous additional stress such as bacterial infection. In addition, the athymic animals produce smaller granulomas and fail to demonstrate accelerated granuloma formation, the spontaneous modulation of granulomas, or significant resistance to reinfection. These deficiencies could be reversed by thymic reconstitution. In vitro studies indicate that the response to egg antigens was due to the interaction of two subpopulations of T lymphocytes. Studies of "in vitro granuloma formation" augmented the in vivo findings, suggesting that the "in vitro granuloma" represents an excellent analog for delayed hypersensitivities; granuloma production was contingent on a macrophage function and a specific subpopulation of T lymphocytes defined as Ly1+. Granuloma modulation was due to two mechanisms, one contingent on direct suppression by ly2,3+ cells and the other by feedback inhibition requiring Ly,2,3+ cells. These studies suggest the feasibility of combined in vivo and in vitro technology to study the mechanisms of granuloma formation and subsequent morbidity.

Effects of portacaval shunting on Schistosoma japonicum infection in chimpanzees: dissociation of pipe-stem fibrosis and glomerulopathy.

Eight of 10 young chimpanzees were infected with the Japanese strain of Schistosoma japonicum. In 6 of these, and in 1 normal chimpanzee, a surgical end-to-side portacaval shunt was constructed during the 8th week of infection. One additional infected chimpanzee was treated successfully with the nitrovinylfuran, SQ 18,506. In the four animals surviving both infection and shunting hepatic portal fibrosis was either absent or mild. In the 7-month survivors and in the drug-treated control animals there was evidence of healed portal endophlebitis and arterialization, but no active schistosomal liver lesion was found. Nevertheless, three of these animals showed variable degrees of active schistosomal glomerulopathy, similar to that seen in the unshunted infected control and to that described in earlier studies. There was a shift of the egg burden from the liver to the lungs, as well as evidence that the number of surviving adult worms had decreased following portacaval shunting. These observations sugggest that schistosomal nephropathy in chimpanzees is more closely related to infection intensity per se than to the degree of liver damage caused by infection.

Role of epidermal growth factor and transforming growth factor alpha in the developing stomach.

AIMS: To determine whether epidermal growth factor (EGF) or the related transforming growth factor alpha (TGF alpha) may have a role in the developing human stomach; to substantiate the presence of EGF in human liquor in the non-stressed infant and whether EGF in amniotic fluid is maternally or fetally derived. METHODS: The temporal expression and localisation of EGF, TGF alpha, and their receptors during fetal and neonatal life were examined in 20 fetal and five infant stomachs. Simultaneously, samples of amniotic fluid and fetal urine from 10 newborn infants were collected and assayed for EGF by radioimmunoassay. RESULTS: EGF immunoreactivity was not noted in any of the specimens examined. In contrast, TGF alpha immunoreactivity was shown in mucous cells from 18 weeks of gestation onwards. EGF receptor immunoreactivity was seen on superficial mucous cells in gastric mucosa from 18 weeks of gestation onwards. The median concentration of EGF was 30 and 8.5 pg/ml in amniotic fluid and fetal urine, respectively, suggesting that EGF is not produced by the fetus. CONCLUSIONS: This study adds weight to the hypothesis that swallowed EGF, probably produced by the amniotic membranes, and locally produced TGF alpha, may have a role in the growth and maturation of the human stomach.

Quantitative changes in astrocytes after portacaval shunting in chimpanzees and in man with normal liver parenchyma.

Chimpanzees without liver cell damage, but subjected to portacaval anastomosis, showed behavioral changes that were accompanied by "Alzheimer II" astrocyte hyperplasia and nuclear enlargement. These findings were similar to those in a human patient with encephalopathy, secondary to a portacaval shunt, whose liver was normal. Controlled quantitative study of astrocytic hyperplasia in different anatomic regions showed the hyperplasia to involve the gray matter with only moderate topographic variation. Individual degrees of hyperplasia somewhat paralleled the severity of clinical symptoms and ammonia levels; no clear-cut relationship with time after shunting could be established. Portacaval shunt encephalopathy in chimpanzees greatly resembles that in man and, thus, lends itself to more detailed experimental analysis.

Cephalic structures in the nemertine Parborlasia corrugatus-Are they really eyes?

The opinion as to whether tiny, approximately 0.1 mm large spots around the innermost margin of the cephalic slits in the Antarctic nemertine worm Parborlasia corrugatus represent photoreceptors or not has fluctuated over the years. This first electron microscope study of the enigmatic spots fails to detect any screening pigment granules, rhabdomeres, or lamellae, but reveals that the structure in question is principally made up of two types of cell, characterized by vesicular and vacuolar material of approximately 80 nm and 0.3 mum in diameter, respectively. Filamentous connective tissue strands with gaps for axons surrounds the 'eye-spot' and it is suggested that either exposure to the bright Antarctic summer light has led to a total disintegration of all visual membranes or these structures do not represent eyes at all.

Synchronized estrus and fertility of beef cows after weaning calves for short intervals.

In Exp. 1, the objective was to determine if interval of separating calves from cows (24 or 48 h) immediately before insemination affects detection and precision of estrus and pregnancy rates of lactating beef cows implanted with norgestomet. Separation of calves from cows for 24 h (n = 418) lengthened intervals to estrus, did not affect precision of estrus, reduced success of detecting estrus and lowered pregnancy rates relative to positive controls (48 h separation, n = 508). Cows with poor body condition, and not suckled for 24 h, conceived at lower rates than cows with similar condition that were not suckled for 48 h. Adverse effects of separation for only 24 h on fertility are apparently due to inadequate intervals between estrus and insemination at 48 h after removing implants. In Exp. 2, the objective was to determine effects of separating calves from cows for 48 h immediately before insemination on detection and precision of estrus and on pregnancy rate of ovulatory lactating beef cows injected twice with prostaglandin F2 alpha (PGF2 alpha). Weaning increased detection of estrus but overall pregnancy rates did not differ between suckled (n = 256) and nonsuckled (n = 221) cows. But, weaning calves improved pregnancy rates of young (2 to 3 yr) cows and reduced fertility among middle (4 to 6 yr)-aged cows. Increased pregnancy rates after weaning calves for 48 h are due largely to greater detection of estrus and inseminating more cows.(ABSTRACT TRUNCATED AT 250 WORDS)

Scanning electron microscopy of the jejunum in children with protein-energy malnutrition.

Samples of jejunum from seven children dying from severe oedematous malnutrition were fixed with intralumenal glutaraldehyde in combination with external immersion, using a rapid autopsy protocol. Selected areas were post-fixed in osmium tetroxide, dehydrated with an ethanol series and critical point dried. After mounting on aluminium stubs, specimens were sputter-coated with a thin layer of gold and palladium. Scanning electron microscopy showed patterns ranging from subtotal villous atrophy, through partial villous atrophy with low ridges, to longer, taller ridges with cerebriform convolutions. In one case, villous height had been interpreted as normal on light microscopy. The scanning electron microscope revealed that the mucosa in this case was composed of ridges and leaf forms. Processing for scanning electron microscopy is simple. The specimens can be viewed and photographed in a relatively short time. In addition, the three-dimensional record provides clarification of ambiguities which often arise from routine histological sections.

Electron microscopy in Jamaica: applications and techniques.

Although the electron microscope was developed about 60 years ago in Germany, its arrival and subsequent use in Jamaica are of considerably more recent date. In this paper, the principles of scanning and transmission electron microscopy (SEM & TEM) are briefly explained, and examples are given of the research done with the electron microscopes at the University of the West Indies (UWI), Mona Campus, Jamaica, especially over the last three years. Detailed descriptions of specimen preparation are provided for both SEM and TEM and particular emphasis is placed on the methodology used in our laboratory, as it sometimes differs from the routine followed in electron microscopy units of temperate countries.

In vitro erythrocytic membrane effects of dibenzyl trisulfide, a secondary metabolite of Petiveria alliacea.

We investigated the in vitro effect of dibenzyl trisulfide (DTS), a secondary metabolite of Petiveria alliacea, on erythrocyte elasticity, relaxation time and membrane morphology. Blood samples from 8 volunteers with hemoglobin AA were exposed to 100, 200, 400, 800 and 1000 ng/ml of DTS respectively and the elasticity and relaxation time measured. There were statistically significant, dose-dependent increases in elasticity and relaxation times. The changes in membrane morphology observed also increased with increased concentration of DTS. This suggests that DTS interaction with membrane protein resulted in increased elasticity, relaxation time and deformation of the erythrocyte membrane.