Diabetes mellitus in chronic active hepatitis and cirrhosis

One hundred consecutive patients with nonautoimmune chronic active hepatitis (51% HBsAg-positive), 50 patients with cirrhosis (38% HBsAg-positive), 25 patients with chronic persistent hepatitis, and 118 patients with hepatoma who were seen at this hospital were reviewed to determine the prevalence and characteristics of glucose intolerance and diabetes in these conditions. Diabetes (fasting serum glucose greater than 7.8 mmol/L, 140 mg/dl on two separate occasions) was present in 8% of patients with chronic persistent hepatitis and mild chronic active hepatitis, 44% of patients with severe chronic active hepatitis, 40% of patients with cirrhosis, and 15% of patients with hepatoma, compared with 7% of all other patients aged 35 yr or over, undergoing liver biopsy. Compared with this high prevalence of diabetes in liver disease, only 3% of diabetic patients referred to the hospital diabetic clinic had chronic hepatitis or cirrhosis. Glucose tolerance was similar in chronic active hepatitis and cirrhosis and was characterized initially by basal hyperinsulinemia, normal basal glucose levels but elevated serum glucose following glucose loading, and evidence of insulin resistance. We suggest that the high prevalence of diabetes in chronic active hepatitis and cirrhosis in Saudi Arabia is due to the insulin resistance of chronic liver disease acting over many years in a population with a high genetic predisposition to diabetes.

The clinical significance of hemoglobinopathies

Hemoglobinopathies may be a significant clinical problem in certain racial groups. A patient presenting with obscure hemolytic anemia should, therefore, be investigated for hemoglobinopathies, particularly if he is of Mediterranean or southeast Asian descent. Longterm iron therapy should not be instituted on the basis of a hypochromic microcytic blood picture without documenting iron deficiency. When investigating polycythemia in young patients with normal white blood cell and platelet counts, hemoglobin oxygen affinity (P50) should be measured.

Isolation and specificity of antibodies to uridine

Antibodies to uridine were produced in rabbits using a conjugate of uridine (periodate oxidized) and bovine serum albumin as immunogen. The specificity of the antibodies was studied by estimating the inhibition of the binding of 3H-uridine-trialcohol to the antibodies by various non-radioactive related compounds, using a nitrocellulose filter assay. The antibodies were 1500-fold more reactive to the uridine-trialcohol than the parent nucleoside. They bound 3H-RNA at homologous base residues. The hapten specific antibodies were purified by affinity chromatography on a uridine-AH-Sepharose column.

Regulation of cyclic nucleotides in retinal photoreceptors. An ultracytochemical approach on the role of cyclases

The distribution of cyclases in retinal photoreceptors of dark- and light-adapted brook trout was studied by means of a cytochemical method (lead precipitation). It confirms earlier reports that retinal photoreceptors contain high levels of cyclic nucleotides, and that cAMP predominates in cones and cGMP in rods. There is an apparent difference in the level of the cyclases with the adaptive states. In addition, the catalytic unit of cyclase is interlamellar in cones. In rods, adenylate cyclase is intradiscal, while the location of guanylate cyclase varies with the adaptive state. The variation of cyclase with adaptation indicates that this enzyme has a role in the process of visual transduction.

The intrauterine diagnosis of hemoglobin disorders

This article presents an overview of the use of fetal blood and DNA for prenatal testing. The molecular organization of the human hemoglobin genes, the structure of human hemoglobins, and the molecular defects of hemoglobinopathies are also discussed.

Specificity and purification of antibodies to adenylic acid

Anti-adenylate antibodies were elicited in rabbits using a conjugate of adenylic acid and bovine serum albumin as immunogen. The specificity of the antibodies was determined by monitoring the inhibition of the binding of [3H]AMP to the antibodies by various nonradioactive nucleic acid components, using a nitrocellulose filter assay. The antibodies were found to be directed against the whole molecule of AMP. They were reactive to polyadenylic acid, RNA, and denatured DNA. The hapten-specific antibodies were isolated by employing an AMP-AH-Sepharose affinity column.

Effect of ascorbic acid in the treatment of tetanus

The effect of daily intravenous administration of 1000 mg ascorbic acid (AA) in tetanus patients aged 1-30 years was studied. In the age group of 1-12 years, 31 patients were treated with AA as additional to antitetanus serum, sedatives and antibiotics. It was found that none of the patients died who received AA along with the conventional antitetanus therapy. On the other hand, 74.2 per cent of the tetanus patients who received the conventional antitetanus therapy without AA (control group) were succumbed to the infection. In the other age group of 13-30 years, there were 27 and 38 patients in the treatment and control groups respectively. The mortality in the AA and control groups were 37 percent and 67.8 percent respectively. These results suggest that AA might play an important role in reducing the mortality of tetanus. This was supported by the fact that AA was found to mitigate the toxic effects of strychnine producing tetanus like condition in young chicks in the present study.

Hb J-Singa (alpha-78 Asn leads to Asp), a newly discovered hemoglobin variant with the same amino acid substitution as one of the two present in Hb J-Singapore (alpha-78 Asn leads to, alpha-79 Ala leads to Gly)

A new fast-moving alpha-chain Hb variant with an Asn leads to Asp substitution at position alpha-78 was found in a French-Acadian family living in Eastern Canada. The identical substitution was reported in Hb J-Singapore, which also had an additional Ala leads to Gly substitution at position alpha-79. The new variant, which did not result in any clinical symptoms, was named accordingly, Hb J-Singa.

Kaposi's sarcoma in renal transplant recipients. Ultrastructural and immunoperoxidase study of four cases

Tissues from four cases of Kaposi's sarcoma developing in renal transplant recipients were studied by light and electron microscopic examination and by immunoperoxidase staining for Factor-VIII-related antigen. Ultrastructurally, the tumors in all four cases contained a variable mixture of cells, including endothelial cells, pericytes, fibroblasts, and myofibroblasts. These findings support the origin of Kaposi's sarcoma from primitive vasoformative mesenchyme. Immunoperoxidase staining for Factor-VIII-related antigen was limited to endothelial cells. In one case intracytoplasmic virus-like tubular complexes were seen. The significance of this finding is briefly discussed.

Kaposi's sarcoma in renal transplant recipients. Ultrastructural and immunoperoxidase study of four cases

Tissues from four cases of Kaposi's sarcoma developing in renal transplant recipients were studied by light and electron microscopic examination and by immunoperoxidase staining for Factor-VIII-related antigen. Ultrastructurally, the tumors in all four cases contained a variable mixture of cells, including endothelial cells, pericytes, fibroblasts, and myofibroblasts. These findings support the origin of Kaposi's sarcoma from primitive vasoformative mesenchyme. Immunoperoxidase staining for Factor-VIII-related antigen was limited to endothelial cells. In one case intracytoplasmic virus-like tubular complexes were seen. The significance of this finding is briefly discussed.

The way we teach… haematology to postgraduates

In this article, the author describes the levels of competence that residents in the postgraduate haematology programme at McMaster University are required to reach. He also discusses the rotations and elective programmes, designed to give postgraduate students experience in the clinical and laboratory setting. An account of the undergraduate haematology programme at McMaster's was published in the last issue of Medical Teacher.

The way we teach… haematology to undergraduates

In this article the author describes the integrated undergraduate haematology course at McMaster University. A novel feature is the 'Triple-Jump Exercise' three-step form of evaluation, which offers an opportunity to assess problem solving, history taking, and data acquisition and formulation in a reasonably standardized way. An account of how haematology is taught at postgraduate level will be published in the next issue of Medical Teacher.

Hemoglobin Hamilton or alpha 2 beta 2 11(A8)Val leads to Ile: a silent beta-chain variant detected by Triton X-100 acid-urea polyacrylamide gel electrophoresis

A silent beta-chain hemoglobin variant, not detectable by starch gel or agar gel electrophoresis was found using Triton X-100 acid-urea polyacrylamide gel electrophoresis. The abnormal beta-X chain had a more anodic electrophoretic mobility; 38% of the total beta chain was of the abnormal type. Structural analysis using high-performance liquid chromatography and microsequencing procedures indicated a valine to isoleucine substitution at position beta 11(A8). This anomaly did not change the functional properties of the hemoglobin molecule. A mild reticulocytosis was observed in the propositus.

Secretory carcinoma of the breast in adults. Light and electron microscopic study of three cases with review of the literature

Three adult cases of secretory carcinoma of the breast were studied by both light and electron microscopy. Histologically the tumors revealed three patterns, namely, solid, microcystic and ductal. Ultrastructurally the tumor cells contained large numbers of membrane-bound intracytoplasmic secretory vacuoles. In addition, numerous intracytoplasmic as well as intercellular lumina containing abundant secretory material were noted. Secretory carcinoma in adults is rare with only twenty cases reported previously in the literature. It is known to have a better prognosis than the usual ductal carcinoma. The most appropriate treatment appears to be an extended simple mastectomy.

Hemoglobin E diseases: hematological, analytical, and biosynthetic studies in homozygotes and double heterozygotes for alpha-thalassemia

Two families with Hb E diseases are described. In the Laotian family S, three homozygous Hb E were found. In the Vietnamese family H, double heterozygous Hb E-alpha-thalassemia-2 and Hb E-Hb H diseases were found. Anemia or hemolysis was absent in Hb E carriers, unless complicated by iron deficiency, the presence of severe alpha-thalassemia gene (Hb H disease), or oxidative drug (paraaminosalicylic acid). Moreover, iron deficiency or concurrent alpha-thalassemia genes resulted in a decreased amount of Hb E in its heterozygous carriers. Mild microcytosis and hypochromia were observed in Hb E heterozygotes, whereas the microcytosis and hypochromia were more pronounced in Hb E homozygotes. Globin chain synthesis studies yielded unbalanced alpha/non-alpha ratios in both heterozygotes and homozygotes (average ratios were 1.13 and 1.56, respectively). The unbalanced biosynthetic ratios with microcytosis and hypochromia in Hb E carriers represented a beta-thalassemia phenotype, which could be a result of reduced synthesis of beta E-globin mRNA, as suggested by recent hybridization studies.

Histological and histometrical studies of testicular hypertrophy following hemicastration of albino rats

This project was designed to study the effects of hemicastration in male albino rats of different ages and weights. Significant compensatory hypertrophy was seen in young rats (5 and 20 days old). The concentration of seminiferous tubules was profoundly reduced while the tubular diameter was increased in young hemicastrated rats. The weights of the kidneys were increased while the weights of the adrenal glands were not different in hemicastrated young rats. These histological and histometrical changes may be associated with specific endocrine activity.

Application of electron microscopy in the interpretation of fine-needle aspiration biopsies

A series of 31 fine-needle aspiration biopsies were studied ultrastructurally in order to evaluate the usefulness of electron microscopy in the diagnosis of aspiration biopsies. In seven cases, the electron microscopic findings were crucial to the diagnosis. In the remaining cases, electron microscopy helped to confirm the light microscopic diagnosis. In addition, in a number of cases the diagnosis rendered following electron microscopy was much more precise and specific than was possible with light microscopy alone. It is concluded that electron microscopy has a definite place in the diagnosis of fine-needle aspiration biopsies and should be increasingly utilized on a selective basis.

Ultrastructure of the pineal organ of the killifish, Fundulus heteroclitus, with special reference to the secretory function

The pineal organ of the killifish, Fundulus heteroclitus, was investigated by electron microscopy under experimental conditions; its general and characteristic features are discussed with respect to the photosensory and secretory function. The strongly convoluted pineal epithelium is usually composed of photoreceptor, ganglion and supporting cells. In addition to the well-differentiated photosensory apparatus, the photoreceptor cell contains presumably immature dense-cored vesicles (140-220 nm in diameter) associated with a well-developed granular endoplasmic reticulum in the perinuclear region and the basal process. These dense-cored vesicles appear rather prominent in fish subjected to darkness. The ganglion cell shows the typical features of a nerve cell; granular endoplasmic reticulum, polysomes, mitochondria and Golgi apparatus are scattered in the electron-lucent cytoplasm around the spherical or oval nucleus. The dendrites of these cells divide into smaller branches and form many sensory synapses with the photoreceptor basal processes. Lipid droplets appear exclusively in the supporting cell, which also contains well-developed granular endoplasmic reticulum and Golgi apparatus. Cytoplasmic protrusions filled with compact dense-cored vesicles (90-220 nm in diameter) are found in dark-adapted fish. The origin of these cytoplasmic protrusions, however, remains unresolved. Thus, the pineal organ of the killifish contains two types of dense-cored vesicles which appear predominantly in darkness. The ultrastructural results suggest that the pineal organ of fish functions not only as a photoreceptor but also as a secretory organ.

[Retinal adaptations to habitat]

Vertebrates have, through the process of evolution, adapted to their photic environment. This is well manifested in the retinal adaptations to various habitats. Although all vertebrates are considered, emphasis is placed on fishes because they form about 50% of the vertebrate species. In addition, they occupy a wide range of habitats, thus retinal modifications of fishes serve as models for all other vertebrates. The present article reviews morphological, physiological and biochemical retinal adaptations. The quality and quantity of light reaching the aquatic organism are functions of the incident light as well as the aquatic environment. Thus, in well lit, clear waters fishes are arhythmic and possess almost equal populations of rods and cones; whereas fishes in dimly lit environments (due to turbidity or depth) have retinas that are more specialised for high sensitivity-multi-banked retinas, long outer segments, grouped photoreceptors, hypertrophied ellipsoid mitochondria, reflecting tapetum. Similarly, the ratio and distribution of visual pigments (rhodopsin and porphyropsin) and S-potential change with respect to fresh/sea water, clear/turbid water and air/aquatic environments. Thus, in fresh waters, where the photic environment shifts to longer wavelengths, porphyropsin predominates; while in land vertebrates and almost all marine fishes the dominant pigment is rhodopsin. With respect to the latter, fishes in turbid, greenish or yellowish coastal waters have 'rhodopsins' with lambda mas above 500 nm; fishes in clear coastal habitats have 'rhodopsins' with lambda max near 500 nm; while those in the blue-lit environment of deep seas have lambda max below 500 nm. The retinal pigment composition is also associated with habitat changes during diadromous migrations in fishes or during amphibian metamorphosis. It is interesting to note that the dorsal and ventral retinas of Rana catesbeiana and Anableps microlepis which view aquatic and aerial environments, respectively, show a predominately porphyropsin-rich dorsal retina compared to a rhodopsin-rich ventral retina. Similar shifts in the S-potential are observed with change in habitats. Fresh water fishes exhibit L-responses with lambda max in longer wavelengths compared to marine fishes where the maximum of the L-response shifted towards shorter wavelengths.