2-[125I]iodomelatonin binding in the brains of four salmonids

[125I]-Labelled iodomelatonin binding to brain membrane preparations was examined in adults of 4 species of salmonid fishes; 3 species were of cultured stock (Arctic charr, Atlantic salmon, rainbow trout) and 1 was taken from the wild (coho salmon). The specific binding of 2-[125I]iodomelatonin to the brain membrane preparations collected from all 4 species was specific, stable, saturable, reversible and of high affinity. Competitive inhibition studies showed that only melatonin, 2-iodomelatonin, 6-chloromelatonin and N-acetylserotonin showed significant inhibition of radioligand binding. In the 4 species studied, the equilibrium dissociation constant (Kd) ranged from 9.3 +/- 0.2 pmol/l in coho salmon to 13.2 +/- 0.7 pmol/l in rainbow trout, and those in rainbow trout were significantly higher (p < 0.05) than in the others. The maximum number of binding sites (Bmax) of the Atlantic salmon preparations (14.3 +/- 0.7 fmol/mg protein) was significantly higher than those of the other 3 species (means ranging from 9.9 to 11.6 fmol/mg protein). Hill coefficients of all 4 species were close to unity indicating one class of binding site. The interspecies differences in Kd and Bmax could not be correlated with phylogeny or life history of the various species. For the three cultured species, samples were collected at both mid-dark and mid-light to examine for diurnal variations; none were found.

Laparoscopic cholecystectomy: analysis of the complications at a community hospital

With the worldwide acceptance of laparoscopic cholecystectomy (LC) as the treatment of choice for symptomatic gallbladder disease, great concern has grown over the spectrum of complications associated with this new procedure. The nature, causes, frequency, as well as ways to avoid these complications have been the subject of many articles and studies. Although it is established that the frequency of the major complications decreases with increased experience, there will still be new surgeons performing the procedure with limited experience in the early stages of their surgical practice. Therefore, continuous efforts should be exerted to bring to a minimum the number of serious morbidities, especially common bile duct injuries. Review of each institution's experience and sharing it with other medical centers may be a valuable approach to achieve this important goal. In this report, we will analyze the spectrum of complications we encountered during our experience with LC as well as some recommendations to avoid some of the serious morbidities related to this procedure.

Small round cell tumor with divergent differentiation: cytologic, histologic, and ultrastructural findings

A case study of desmoplastic small round cell tumor with divergent differentiation in a 13-yr-old boy is presented. Clinical, cytologic, histologic, immunohistochemical, and ultrastructural findings are reported. There was a close correlation between the various histologic and cytologic patterns. Immunohistochemical studies revealed strong positivity of many of the tumor cells for cytokeratin, vimentin, and desmin. Ultrastructurally, some of the tumor cells contained aggregates of cytoplasmic intermediate filaments. Fine-needle aspiration biopsy may suggest the diagnosis of desmoplastic small round cell tumor. Confirmation of the diagnosis may be provided by immunohistochemistry and electromicroscopy.

Effect of multiple light scattering and self-absorption on the fluorescence and excitation spectra of dyes in random media

The absorption, fluorescence, and excitation spectra of a dye in a highly scattering random medium were studied experimentally. The intrinsic absorption spectrum of the dye does not change in the presence of scatterers, but the presence of scatterers in the media will change the observed fluorescence spectra. The observation is accounted for by the change in the photon trajectory path length for the fluorescence emission.

Apparent absence of BCL-2 rearrangement in ten Saudi follicular lymphomas: A preliminary report

Specific chromosomal translocations are often found to be associated with distinct types of human neoplasms. The t(14;18) is considered to be a cytogenetic hallmark of the follicular lymphomas found mostly in American patients. This chromosomal translocation occurs through a 3' untranslated region (either major breakpoint region [mbr] or minor cluster region [mcr]) of the bcl-2 proto-oncogene in chromosome 18 and the JH region of the immunoglobulin (Ig) gene in chromosome 14. In the present study, the polymerase chain reaction (PCR) was used to detect a fusion DNA fragment generated from bcl-2/JH rearrangement either through mbr or mcr in 10 follicular lymphomas in Saudi Arab patients. Surprisingly, none of these cases showed any evidence of bcl-2 gene rearrangement through mbr or mcr. The absence of usual bcl-2/JH recombination in Saudi follicular lymphomas is intriguing and may suggest that the occurrence and mode of bcl-2 gene rearrangement in this lymphoma varies in different patient populations.

Multiple circadian oscillators in the photosensitive pike pineal gland: a study using organ and cell culture

The fish pineal organ contains typical and, in some species, modified photoreceptor cells involved in the photoperiodic control of melatonin production. In the majority of species studied, the rhythm in melatonin production is driven by an intra-pineal circadian oscillator synchronized by the light:dark cycle. In the present study, it is shown that the endogenous rhythm in melatonin release of superfused pike pineals maintained under constant darkness is expressed at temperatures of 19 degrees C, 20 degrees C, 25 degrees C, and 30 degrees C (period > 24 hr), but not at temperatures of 10 degrees C and 15 degrees C. Under constant darkness, pineal fractions containing either typical photoreceptors, modified photoreceptors, or both behaved like total organs. Dissociated pike pineal cells, cultured statically at 20 degrees C, expressed a high amplitude rhythm in melatonin secretion under a light:dark cycle. Under constant darkness, circadian oscillations, which appeared better sustained than in organ culture, were also observed. This study provides the first evidence that the rhythmic production of melatonin, by a fish pineal, is driven by a population of circadian oscillators or clocks. It is hypothesized that each typical and modified photoreceptor might be the locus of a circadian clock. Damping of the overall rhythm under constant darkness might reflect the desynchronization (uncoupling) between these clocks and/or damping of individual oscillators.

Myelodysplastic syndrome with prolonged reticulocyte survival mimicking hemolytic disease

A patient with myelodysplastic syndrome (refractory anemia) with marked and persistent reticulocytosis is presented. A referring diagnosis of hemolytic disease had been made. However, the 51Cr red cell survival was normal (T1/2 24 days). Reticulocyte morphology, red cell creatine content, and in vitro reticulocyte survival studies have suggested that the reticulocytosis arose as a consequence of delayed maturation of the reticulocytes. Two patients with myelodysplastic syndrome and delayed reticulocyte maturation have previously been described; in both patients, however, red cell survival was also shortened. Anemia with reticulocytosis, mimicking hemolytic disease, may be an unusual presentation of myelodysplastic syndrome.

Histologically advanced chronic hepatitis C treated with recombinant alpha-interferon: a randomized placebo-controlled double-blind cross-over study

Chronic hepatitis C is common in Saudi Arabia and most often presents in an advanced stage. To assess the response of patients to interferon, a randomized placebo-controlled double-blind study was undertaken. All but 1 patient had cirrhosis or fibrosis before interferon. After a 24-week observation period patients received alpha 2a interferon, 3 mega units sc tiw or placebo for 24 weeks, then the opposite treatment for another 24 weeks followed by 24 weeks of observation. Liver biopsies were performed before and after each of the treatment phases. Twenty-two out of 24 patients completed the study. The mean alanine aminotransferase (ALT) levels fell from 150.7 +/- 118.7 units/l to 91.0 +/- 42.6 units/l after 6 months interferon treatment (P = 0.03) but only 3 patients (14%) had complete normalization of mean ALT levels and 4 (18%) had > 50% reduction. The mean hepatitis activity index fell from 12.2 +/- 2.6 immediately before to 11.6 +/- 2.5 just after interferon (P = 0.4). After interferon there was an insignificant raise in 6-month mean ALT. Hepatitis C virus-RNA was positive in all 17 patients tested and remained so after treatment. Side-effects were mild and well tolerated. Alpha interferon 3 mega units tiw for 24 weeks is not an effective treatment of histologically advanced chronic hepatitis C.

Fine-needle aspiration biopsy of Langerhans histiocytosis (histiocytosis-X)

A series of 14 fine-needle aspiration biopsies (FNAB) from histologically proven cases of histiocytosis-x (Hx) were reviewed. The smears revealed a variable mixture of Langerhans cells, eosinophils, macrophages, polymorphonuclear cells, and giant cells. Based on the predominant cells present, the cases were further categorized as Langerhans cell predominant (nine cases), eosinophil predominant (two cases), and macrophage predominant (three cases). Langerhans cells were usually polygonal without significant evidence of phagocytosis and frequently contained indented nuclei. In three cases, several Langerhans cells showed prominent dendritic processes. Electron microscopy in 10 cases revealed Langerhans cells with varying degrees of morphologic differentiation. All cases studied revealed Birbeck granules. These findings indicate that FNAB may be an effective technique for diagnosing Hx.

Light and electron microscopic observations on rat molar periodontal ligament after intraperitoneal injection of vinblastine

The effect of intraperitoneal injection of Vinblastine sulfate on rat periodontal ligament was studied. Cells still synthetize collagen after 2 hours of the injection with evidence of loss of extracellular collagen fibers orientation. Tubular lysosome could not be detected after 2 hours with formation of lysosomal clusters in the cell center. After 4 hours of administration, evidences of cell degeneration were observed. The present study has shown that Vinblastine produces effect on fibroblasts as early as two hours after injection.

Lysosomal system of von Ebner's salivary gland in the rat

We have examined the morphology and distribution of lysosomes in von Ebner's salivary gland utilizing TMPase as a marker. TMPase reactivity was detected basally, laterally and in the center of the cells. They include AV, Rb, MVBs and dense bodies. TL were detected for the first time in between the secretory granules and in the lateral parts of exocrine acinar cells. They were parallel to RER. In addition direct continuity between TL and MVBs and dense bodies was observed. The new locations and relations of TL supports their role in pinocytotic processes and cellular regularity processes.

Chronic non-A, non-B hepatitis complicated by end-stage renal failure treated with recombinant interferon alpha

Chronic non-A, non-B hepatitis occurs in 50% of Saudi patients with end-stage renal failure and requires long-term hemodialysis since it is a contraindication to renal transplantation. Thirteen patients with biochemical and histological documented chronic non-A, non-B hepatitis (11 with HCV antibodies) entered a double-blind placebo controlled cross-over study, in which Roferon A 3 MU or placebo were administered subcutaneously 3 times weekly after hemodialysis for 6 months. The mean ALT fell significantly from pretreatment levels of 74.7 (95% confidence interval (CI) 54.7, 92.5) (13 patients in the 6-month run-in period) and 66.8 (CI 47.7, 85.8) (7 patients in the run-in period + 6 patients in the placebo period) (difference NS) to 37.6 (CI 21.0, 54.2) during interferon treatment (P < 0.005). In 10/13 patients (77%) ALT levels became normal. In the 6-month follow-up period immediately after therapy, the mean ALT was 45.2 (CI 28.0, 62.0). Although this change was not significant (P = 0.49), only 7 of these 10 patients sustained biochemical remission in the 6-month follow-up period. The corresponding total Histological Activity Index improved from 8.9 (CI 7.5, 10.3), 8.9 (CI 7.2, 10.7) (difference NS) to 6.2 (CI 3.9, 8.5) (P < 0.05; P = 0.052, respectively). Intralobular inflammation and periportal inflammation showed the most significant changes. Five of 13 (39%) and 2/13 patients (15%) had complete resolution of piecemeal necrosis and intralobular inflammation, respectively. Toxic effects of interferon were mild, early and self-limiting.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary hepatic vipoma

A 35-yr-old male presented with a 3-yr history of voluminous watery diarrhea. He had episodes of severe generalized weakness which responded to fluid and electrolyte replacement therapy. Investigations revealed a solitary liver mass and an elevated vasoactive intestinal polypeptide level. An extensive work-up did not show any other extrahepatic primary lesion. Surgical resection ameliorated all of his symptoms, accompanied by a decrease in the vasoactive intestinal polypeptide level. We believe that this patient represents a case of primary hepatic vipoma syndrome. To our present knowledge, this has not been reported previously. We discuss the clinical manifestations, investigations, and management of the case.

Effects of mesencephalic lesion on testes, seminal vesicles and adrenal glands of albino rats

The role of mesencephalic reticular formation on testicular structure, seminal vesicles, adrenal glands and kidneys of albino rats was investigated. Mesencephalic reticular formation lesions were produced using two epoxy-coated stainless steel electrodes. Electrolytic lesions resulted in atrophy of the testes, seminal vesicles and adrenal glands. The degree of atrophy was statistically significant in these organs (P < 0.01). However, there were no significant changes in the kidneys of lesioned animals. This study strongly suggests that the mesencephalic reticular formation influences the histomorphology of testes, seminal vesicles and adrenal glands.

Giant cell tumour of bone. A surgical approach to grade III tumours

Thirty-one patients with giant cell tumours of bone (BGCT) were treated at our hospital by a conservative approach between 1975 and 1988. 94% of the tumours were grade III (Campanacci) and the follow up was from 2 to 13 years. In the 20 patients who had a modified intralesional excision (curettage) with bone grafting and cement, 5 recurrences occurred. There was one soft tissue recurrence in the 11 patients who had marginal or wide excisions. All recurrences were in grade III lesions. We conclude that grade III BGCT can be treated by modified intralesional excision provided the articular surfaces and part of the metaphysis are intact.

Trends in urban violence: a comparison of accident department and police records

Police crime statistics and crime survey data are known to be poor indicators of levels of violence in society. Longitudinal investigations of assault injury have not been carried out in accident and emergency departments hitherto, but may provide an accurate perspective of trends in violence. The attendance of assault patients at a city centre accident and emergency department was compared with 'wounding against the person' recorded by the police between 1973 and 1990. Woundings recorded by the police increased consistently throughout the study period whereas the number of assault patients did not increase between 1977 and 1987. From 1975 to 1990, police statistics showed a 9-fold and accident and emergency data a 6-fold increase. Both data sets showed substantial overall increases in violence after 1987, and a decrease in 1979. Further epidemiological studies of violence are necessary.

Serum CA-15.3 and CEA patterns in postsurgical follow-up, and in monitoring clinical course of metastatic cancer in patients with breast carcinoma

Serum CA-15.3 and CEA levels were longitudinally determined in 307 patients with breast carcinoma during postsurgical follow-up and/or therapy. Of 120 patients with no apparent disease, the specificity of marker levels fluctuating within the normal range (true-negative) was 98% for CA-15.3 alone (P = 0.004) and about 88% for CEA alone or for the tests combined. However, the false-negative levels in patients with progressive cancer reduced the predictive value of the tandem to around 76%, i.e. normal levels of both markers correctly predicted uneventful postsurgical course in only three fourths of the patients. Of 187 patients with active disease, the sensitivity of raised or increasing marker levels was around 70% for CA-15.3 alone or CEA alone, and 82% for the tests combined (P = 0.006). The 11% false-positive rate of CEA in patients with no apparent disease decreased the predictive value of a positive test from 98% for CA-15.3 alone (P = 0.006) to 91% for CEA alone or the tandem. Serum CA-15.3 or CEA paralleled the site of relapse: at least one marker was found elevated in 60% of patients with locoregional disease or with metastases to the lungs or bones exclusively, and in 90% of those with metastases to the lungs and bones or to the liver. A concurrent decrease of both marker levels reflected response to therapy while an increase of at least one marker level reflected treatment failure. It may be concluded that the marker tandem was better than either marker alone for follow-up aimed at detection of relapse, and that the tests were approximately 80% accurate for follow-up and/or monitoring therapy.

Melatonin secretion in vitro from the pineal complex of the lamprey Petromyzon marinus

Melatonin secretion from cultured pineal complexes of the lamprey, Petromyzon marinus, was measured by radioimmunoassay (RIA) for 6 days under either a 12:12 light:dark cycle (L:D) or continuous darkness (D:D) at either 10 degrees or 20 degrees. Under the L:D cycle, melatonin release was completely suppressed during daytime and high during night-time, with larger amplitude at 20 degrees than at 10 degrees. Under D:D conditions, no significant circadian rhythmicity in secretion could be revealed by periodogram analysis at either 10 degrees or 20 degrees. This is the first direct evidence of melatonin secretion in a lamprey, suggesting that both light and temperature can affect in vitro melatonin secretion.

Relations between epidermal growth factor receptor and oestrogen and progesterone receptors in breast cancers of premenopausal and postmenopausal patients in Kuwait

The levels of cell membrane epidermal growth factor receptor EGFR and cytosol (c) and nuclear (n), oestrogen (E) and progesterone (P) receptors (R) were determined in 132 specimens of primary breast cancers. In the tumours of postmenopausal women an inverse significant correlation was demonstrated between the concentrations of EGFR vs. ERc, ERn, and PRc while no such correlation was noted in the tumours of premenopausal women. Premenopausal and postmenopausal EGFR positive tumours (> or = 10 fmol/mg membrane protein) could be regarded as homogenous with respect to the concentration of ER and PR whose mean values were low and without being significantly different. EGFR negative tumours were heterogeneous with respect to the ER and PR concentrations. Postmenopausal EGFR negative (< 10 fmol/mg membrane protein) tumours had evidently higher mean values of ER and PR than premenopausal EGFR negative tumours, but these differences were statistically significant for oestrogen receptors only. The levels of ER and PR of premenopausal EGFR negative tumours were approximated to the corresponding levels of EGFR positive tumours.

Potential and limitations of energy-transfer processes in pulsed and cw dye laser mixtures: comparison of theory and experiments

A comprehensive energy-transfer dye laser (ETDL) simulation model and the premise on which it is based are examined and reviewed. The model permits theoretical predictions of the total transfer efficiency and hence identification of the appropriate mechanisms that are responsible for energy transfer as well as predicting fluorescence spectra of dye mixtures. Using concentration regimes that are generally applicable to laser action, we also show that the model is capable of predicting gain line shapes (and hence tunability) for pulsed ETDL's. An extension of the model also predicts the gain spectrum of cw laser-pumped ETDL's as a function of donor and acceptor concentrations, their spectral data, energytransfer parameters, pump power and wavelength, and dimensions of the active region. Model simulation results are checked against experimental results for pulsed and cw ETDL's with laser outputs in the visible and near-IR spectral regions. The results lead to a better and more detailed understanding of ETDL mec hanisms and the role that the triplet states play in these mechanisms.

Fine-needle aspiration biopsy diagnosis of rhabdomyosarcoma: cytologic, histologic, and ultrastructural correlations

A series of 15 cases of rhabdomyosarcoma diagnosed by fine-needle aspiration biopsy (FNAB) and confirmed by histopathology is reviewed. Cytologically, the tumors were composed of a variable mixture of cells, which according to the degree of differentiation were categorized as early, intermediate, or late rhabdomyoblasts. Histologically, the tumors were divided into embryonal 9, monomorphic round cell 4, and alveolar rhabdomyosarcoma 2. Comparison of histological and cytological features revealed that embryonal types were composed mainly of early rhabdomyoblasts. Recognition of these patterns may be helpful in FNAB diagnosis of rhabdomyosarcoma.

A prospective study to determine the safety of omitting the antiglobulin crossmatch from pretransfusion testing

Transfusion medicine laboratories routinely perform a series of pretransfusion serological tests including: ABO grouping, Rh typing, and investigation of the recipient's serum to detect antibodies against blood group antigens (antibody screen). As a final check, most laboratories also perform a crossmatch in which the recipient's serum is incubated with the donor's red cells followed by the addition of an antiglobulin reagent (antiglobulin crossmatch). The need for the antiglobulin crossmatch when the antibody screen is negative has been questioned because there are few antibodies that are detected by this test. Such antibodies are usually directed against low incidence antigens that are not expressed on the screening cells and in many cases the clinical importance of these antibodies is uncertain. For these reasons, we performed a prospective study in which patients requiring red cell transfusion had a group and screen performed. If the antibody screen was negative the antiglobulin crossmatch was omitted. Following the transfusion of the blood, the antiglobulin crossmatch was performed to look for any potential incompatibility. All patients were monitored both serologically and clinically. Over the 2-year interval of the study 9128 patients were entered. There were 8936 patients (97.9%) with a negative antibody screen and 26.9% (2404 patients) were transfused a total of 10,899 red cell concentrates. The antiglobulin crossmatch performed after the transfusion indicated that 168 red cell concentrates (1.5%) would have been incompatible if the antiglobulin crossmatch had been performed pretransfusion. These 168 red cell concentrates were transfused to 119 patients during 130 transfusion episodes (defined as all transfusions administered within 24 h). Of the 130 transfusion episodes, 79.2% (103/130) were false positive laboratory results. There were 27 transfusion episodes where the antiglobulin crossmatch on blood transfused was positive due to an IgG antibody. Even though these transfused red cell concentrates were designated incompatible by the antiglobulin crossmatch, none of the patients receiving this blood had clinical or serological evidence of haemolysis. We concluded that the antiglobulin phase of the crossmatch can be omitted from pretransfusion testing without putting patients at risk.