Binding of the ligand [3H]MK-801 to the MK-801 binding site of the N-methyl-D-aspartate receptor during experimental encephalopathy from acute liver failure and from acute hyperammonemia in the rabbit

Binding of the ligand [3H]MK-801 to the MK-801 binding site of the N-methyl-D-aspartate (NMDA) receptor population on brain homogenates in rabbits was studied during experimental encephalopathy from acute liver failure and from acute hyperammonemia in the rabbit. Homogenates were prepared from brain cortex, hippocampus and striatum. Hepatic encephalopathy was induced by a two-stage liver devascularization procedure and acute hyperammonemia by a prolonged ammonium-acetate infusion; rabbits receiving a sodium-potassium-acetate infusion served as controls. In these animal models extracellular brain glutamate levels are known to be elevated. However no significant alterations in the number nor the affinity of the MK-801 binding sites of the NMDA receptors were found during acute liver failure and acute hyperammonemia. These findings suggest that the NMDA receptor population remains unaltered in experimental encephalopathy from acute liver failure and acute hyperammonemia, despite alterations in extracellular brain glutamate levels.

[Morphometric evaluation on the pathologic changes in ovariectomized endometria influenced by estrogen use]

Thirty SD female rats were divided into the following groups: (1) sham operation; (2) bilateral ovariectomized (OVX); (3) OVX and estrogen-treated (E). Computerized Image Analyser was used to evaluate the pathologic changes of endometria in these animals. The results showed the endometria of OVX group was in the state of atrophia, while the endometria of E group was in the state of early proliferative stage. The heights of endometria, endometrial epithelia cells and gland epithelia cells, the volume fraction and numerical density of endometrial glands, and the cavity diameter of the glands could effectively express the proliferative changes of the endometria. It is suggested that this method be used to study the pathology of the different endometric diseases.

Regulatory elements necessary for termination of transcription within the Ig heavy chain gene locus

Previous experiments have shown that the extent of delta gene transcription during B cell development is regulated primarily at the transcriptional level. We have shown that deletion of a sequence located between the mu and delta coding regions in the Ig heavy chain locus where transcriptional termination has been previously mapped abrogates the termination. Restoration of termination requires reintroduction of this segment as well as sequence elements within the microM poly (A) site which cannot be substituted by the microS poly (A) site. Recognition of the termination site by non-lymphoid cells suggests that initiation of delta transcription in mature B lymphocytes requires the activation of an anti-termination mechanism not yet developed in early B cells.

[The role of hemorheologic disturbance in experimental acute pancreatitis]

The role of hemorheologic disturbance in experimental acute pancreatitis was studied in Wistar male rats. It was found that pancreatic duct obstruction with secretin stimulation could induce acute interstitial pancreatitis (AIP), but when high molecular dextran intravenous injection being added, acute necrotizing pancreatitis (ANP) was induced. The authors suggest that the high molecular dextran can increase blood viscosity, aggregation of erythrocytes and decrease erythrocyte deformability, which results in pancreatic microcirculatory disturbances and promotes progressive pancreatic necrosis. Hemorheologic disturbance is one of the key factors in the pathogenesis of ANP.

[Nilestriol prevents osteoporosis in ovariectomized rats]

In order to determine the effects and mechanism of Nilestriol upon bone metabolism, 4-month aged female SD rats were divided randomly into three groups: The OVX group subjected to bilateral ovariectomy, the SHAM group to sham operation, the Nilestriol (CEE3) group to bilateral ovariectomy and treated with CEE3 0.15 mg/100 g BW once a week for 10 weeks. The CEE3 was introduced directly into the stomach from the first day after operation. All rats were killed 10 weeks after operation and their right proximal tibiae were processed undercalcified for quantitative bone histomorphometry. The weights of bone and inorganic matter (ash content) and content of calcium, phosphorus of right humeral were measured. The results showed that in the OVX group the trabecular bone volume, the trabecular thickness, the content of calcium bone, and the ratios of bone weight and ash weight to body weight were all significantly reduced. The bone loss was associated with an increase in bone remodeling; the bone resorption appeared much more marked than the bone formation. In contrast, the ovariectomized animals treated with CEE3 had normalization of bone mass and a declined index of bone resorption and formation which recovered the balance of bone remodeling. It suggested that CEE3 is successful in prevention of bone loss in OVX rats. It is convinced of using Nilestriol to prevent postmenopausal osteoporosis.

Cardiac dimensions determined by cross-sectional echocardiography in the normal human fetus from 18 weeks to term

Assessment of cardiac dimensions of the chambers, great arteries and veins in the human fetus is important to distinguish abnormal dimensions from normal. This study establishes normal values based on cross-sectional echocardiographic measurements over the gestational period where these measurements may be clinically useful. Ventricular and atrial dimensions were measured from the 4-chamber view, the short-axis dimension immediately below the mitral and tricuspid valve leaflets in diastole, and the long axis from the closed apposed atrioventricular valves to their respective apices. The ventricular walls and septum were measured at the level at which cavity dimensions in diastole were measured, defining both the left and right ventricular wall thickness, as well as that of the ventricular septum. Furthermore, the long axis of the right and left atria was measured from the center of the apposed atrioventricular valve leaflets to the posterior atrial wall, and the sizes of the atrial chambers were defined using their widths at the prospective broadest points through the area of foramen ovale. From a variety of views, diameters were measured at maximal expansion of the main, left and right pulmonary arteries, the ductus arteriosus, and the superior and inferior venae cavae. The data were evaluated longitudinally from 18 weeks to term, and regression analysis was performed using the best fit of a linear or polynomial equation. The data provide a means for evaluating the normal sizes and dimensions of the fetal heart chambers, as well as the thickness of the ventricular walls and septum.

Detection of genital human papillomavirus (HPV) DNA by PCR and other conventional hybridisation techniques in male partners of women with abnormal Papanicolaou smears

OBJECTIVE

To study the prevalence of human papillomavirus (HPV) infection, using several different hybridisation techniques, in men whose female sexual partners had cervical HPV and/or cervical intraepithelial neoplasia (CIN).

METHODS

The male genital area was examined colposcopically and areas suspicious of HPV changes were biopsied. Each biopsy was subjected to histological examination and HPV DNA analysis by conventional DNA analysis such as Southern, reverse and dot blot as well as with polymerase chain reaction (PCR).

RESULTS

Colposcopic examination of men showed 133 to be normal whilst 82 (38%) had clinical or subclinical lesions. Of 55 colposcopically directed biopsies from the male lesions taken, detection of HPV DNA by hybridisation with conventional techniques and by PCR showed HPV DNA in 29 (53%) and 47 (85%) of biopsies respectively. Overall HPV types 6/11 were the predominant types. In 18 (33%) biopsies positive by PCR, multiple types were found.

CONCLUSION

HPV DNA was present in the majority of biopsy specimens taken, with HPV 6/11 being the predominant type. Among methods for HPV DNA detection, PCR was the most sensitive and useful technique.

[Changes in glomerular polyanions and ultrastructure induced by protamine in rats]

Perfusion of rat kidneys with polycation protamine, resulted in pathologic alterations of glomeruli very similar to those observed in minimal change nephrotic syndrome in human. In the experimental model, colloidal iron stained kidney tissue sections were analyzed quantitatively by image analyzer and stereology in combination with the observation of other glomerular ultrastructure. The mean thickness of foot processes and the foot processes making up the volume fraction of glomerular capillary were determined. The studies showed that there was a significant decrease in glomerular polyanions of kidneys perfused with protamine as compared with that of the control group (P < 0.01). The glomerular alterations included swelling and fusion of foot processes and narrowing or loss of filtration slits. Electron-dense particles formed by binding of protamine to polyanions were seen primarily in the lamina rara externa of glomerular basement membrane and also along the lamina rara interna and on the foot process surface, which showed the distribution feature of glomerular filter. These results suggest that the ultrastructure alterations of glomeruli may result from the neutralization of polyanions by perfusion with protamine.

Retinal artery occlusion in a diver

The clinical manifestation of decompression disorders is highly variable, ranging from mild rashes or joint pains to central nervous system symptoms like scotomata, paralysis and death. The diagnosis is easily overlooked, especially if an occupational history is not obtained. Recompression treatment with hyperbaric oxygen is the specific treatment for decompression sickness and air embolism. Prompt recognition and treatment are vital to recovery. However, there is a place for treatment of decompression disorders and embolism even when significant delay of up to 14 days has occurred. This case report discusses decompression disorders in relation to an unskilled fisherman diver who present with retinal artery occlusion. Decompression disorder leading to retinal artery occlusion is a very rare presentation. The difficulty of diagnosis is discussed as well as the result of delayed hyperbaric treatment.

[Antisteatotic effects of four kinds of dietary fibers in rats fed on high cholesterol diet: a preliminary morphometric analysis]

The hypolipidaemic and antisteatotic effects of the Konnyaku Powder (KP) have been reported before. In order to evaluate further the antisteatotic role played by KP, the effects of KP on the levels of liver lipid and on the hepatic histopathology and morphometry in comparison with those of pectin, algin and agar were studied. Sixty Wistar strain rats were divided into 6 groups: a normal diet group, a high cholesterol diet group (HC), and 4 test groups, in which the animals were fed on a diet similar to that of the high cholesterol diet group with addition of KP, pectin, algin or agar at a dosage of 5%, respectively. All the animals were killed at the end of the diet treatment for 9 weeks. The results showed that relative liver weights were lower in four experimental groups than in the HC group. The levels of total and free cholesterol, and triglyceride in the liver were lower in KP group than in HC group and in the other three experimental groups. Hepatic histopathology and morphometric examination indicated that antisteatotic effects of KP appeared to be much more significant than those of the other fibers.

Primary structure of the assimilatory-type sulfite reductase from Desulfovibrio vulgaris (Hildenborough): cloning and nucleotide sequence of the reductase gene

The nucleotide sequence encoding the structural gene (651 bp) and flanking regions for the assimilatory-type sulfite reductase from the sulfate-reducing bacterium Desulfovibrio vulgaris (Hildenborough) was determined after cloning a 1.4 kb HindIII/SalI genomic fragment possessing the gene into Bluescript pBS(+)KS. The primary structure of the protein was deduced, and the molecular mass of the apoprotein was estimated as 24 kDa. The amino acid sequence of the polypeptide shows some similarities at putative [Fe4S4] cluster binding sites in comparison with the heme protein subunit of the larger Escherichia coli and Salmonella typhimurium sulfite reductases and spinach nitrite reductase. This is the first reported sequence of a member of a new class of low molecular weight assimilatory sulfite-reducing enzymes recently identified in a number of anaerobic bacteria [Moura, I., Lina, A. R., Moura, J. J. G., Xavier, A. V., Fauque, G., Peck, H. D., & Le Gall, J. (1986) Biochem. Biophys. Res. Commun. 141, 1032-1041].

Enzymatic redox chemistry: a proposed reaction pathway for the six-electron reduction of SO3(2-) to S2- by the assimilatory-type sulfite reductase from Desulfovibrio vulgaris (Hildenborough)

A detailed reaction pathway for the six-electron reduction of SO3(2-) to S2- by the assimilatory-type sulfite reductase (SiR) from Desulfovibrio vulgaris (Hildenborough) has been deduced from experiments with 35S-labeled enzyme and the relative reaction rates of nitrogenous substrates. The ligand bridging the prosthetic [Fe4S4]-siroheme center is apparently exchanged by 35S2- in both oxidized and reduced enzyme. This 35S2- label was retained in the course of SO3(2-) reduction, implicating substrate binding to the nonbridging axial site of the siroheme. A reaction mechanism is proposed in which SO3(2-) binds to Fe2+ through the sulfur atom, followed by a series of two-electron reductive cleavages of S-O bonds. Protonation of oxygen facilitates bond cleavage, giving hydroxide as leaving group. The bridge remains intact throughout the course of the reaction, providing an efficient coupling pathway for electron transfer between the cluster and siroheme.

Efficient transformation and regeneration of rice small cell groups

Transgenic plants have been regenerated from small cell groups of rice using a simpler, faster, and more efficient method than used previously (e.g., protoplast transformation and regeneration methods). Small cell groups of 50-100 cells were prepared from established suspension cultures of rice cell lines. Transformation of small cell groups with intact cell walls was carried out with a plasmid harboring the beta-glucuronidase gene and was mediated by polyethylene glycol. Assay of beta-glucuronidase activity indicated that the frequency of transformation was about 7%. beta-Glucuronidase activity was detected in the roots and leaves of plants regenerated from transformed calli. One or two copies of the beta-glucuronidase gene per cell were determined to be integrated into the rice chromosomal DNA isolated from transformed calli. This method of transformation and regeneration is widely applicable to both dicotyledonous and monocotyledonous plants, especially those varieties that are resistant to regeneration from protoplasts.

Monovalent Fab fragments of D7.5 monoclonal antibody activate intracellular Ca2+ mobilization and secretion of cytolytic factors by thymus cells

Previous studies have identified two mouse monoclonal antibodies, D7.5 and G1.4, that each can cause secretion of cytolytic factors from natural killer (NK) cells and resting T cells in humans, rats, and hamsters. Toward elucidation of the molecular identity and the transmembrane signaling mechanism of the antibody-defined trigger molecules, we investigated 1) their surface density, 2) the crosslinking requirement for signaling, and 3) their ability to mobilize intracellular calcium ions. Equilibrium binding studies using monovalent Fab fragments of D7.5 showed the presence of approximately 20,000 trigger molecules per thymus cell and an antibody dissociation constant of 1.8 x 10(-6) M. Thymus cells incubated in the presence of either intact or Fab fragments of D7.5 acquired the ability to lyse Yac-1 cells. Furthermore, the incubation media of thymocytes that were treated with either intact or Fab fragments of D7.5 contained effector-cell derived factors that could lyse Yac-1 cells. Flow cytometry measurements of changes in intracellular free calcium concentration ([Ca2+]i) in thymocytes. A significantly elevated level of [Ca2+]i was observed at 60s after antibody addition and this response, which required the external calcium source, increased continuously during the 30 min incubation. Furthermore, dbcAMP plus theophylline did not alter the ability of D7.5 to induce calcium mobilization suggesting that the antibody-defined trigger may not use the signaling pathway involving breakdown of phosphatidylinositol.

New type of X-linked progressive muscular dystrophy involving shoulder girdle and back

A new type of X-linked muscular dystrophy is described in a family in which 7 men had boyhood onset of progressive dystrophy involving muscles of the shoulder and back but not the calves or face. The scapula-back muscles are affected, but the calf muscles are normal. All patients are still able to walk. The oldest patient is now 37 years old. The muscular dystrophy has been specified by electromyography, pathologic tissue microscopic examination, electron microscopic study, and elevated CK. This type of muscular dystrophy has not been reported previously.

Pulmonary artery involvement in aorto-arteritis. An analysis of DSA

Angiographic features of the pulmonary artery were studied in 24 patients with aortoarteritis (Takayasu's arteritis) by digital subtraction angiography. The pulmonary artery involvement was found in nine cases (37.5%). The right side was involved in eight and the left side in five cases. The right pulmonary artery was involved in two cases, the lobar artery in six, the segmental artery in six, and subsegmental as well as peripheral branches in four. The angiographic features were stenosis and/or occlusion as were the changes of the systemic arteries in aorto-arteritis. The aorta and its main branches were involved in all nine patients, but the severity of pulmonary vascular changes was not always related to the systemic vascular changes. Bronchial angiography demonstrated enlarged and tortuous bronchial arteries in four cases. Lung ECT revealed abnormalities in four cases.

The embryonal development of the human eye photoreceptors

The development of the photoreceptors of human embryos and fetuses dating from 7 weeks to term were studied. The outer segments of rods and cones began to form at the seventh month. The arrangement of the newly formed discs were not regular, but at term they were arranged parallel to each other and perpendicular to the long axes of the outer segments. At the 9th month, no phagosome containing discs was seen in the pigment epithelial cells, but they were discerned in those of the term fetuses.

Development of a novel series of (2-quinolinylmethoxy)phenyl-containing compounds as high-affinity leukotriene receptor antagonists. 1. Initial structure-activity relationships

This series of reports describes the development of orally active, highly potent, specific antagonists of the peptidoleukotrienes containing a (2-quinolinylmethoxy)phenyl moiety. Described in this first report are the structure-activity relationships that led to a more than a 20-fold improvement of the potency and selectivity of the initial chemical lead (RG 5901). From this series of compounds, RG 7152 (16) was identified and selected for further evaluation in the clinic as an antiasthmatic agent. Compound 16 competitively inhibits [3H]LTD4 binding to membranes from guinea pig lung (Ki = 38 +/- 6 nM) and the spasmogenic activity of LTC4, LTD4, and LTE4 in parenchymal lung strips from guinea pigs. Unlike the original lead (RG 5901), compound 16 does not inhibit 5-lipoxygenase from guinea pig PMNs. Following oral administration to guinea pigs, 16 blocks LTD4-induced dermal permeability (ED50 = 6.9 mg/kg), LTD4-induced bronchoconstriction (ED50 = 1.1 mg/kg), antigen-induced bronchoconstriction (ED50 = 2.5 mg/kg), and anaphylactic-induced mortality (ED50 = 16 mg/kg). These studies on structure-activity relationships indicate that there is a requirement for an acidic function and the presence of the (2-quinolinylmethoxy)phenyl moiety in a specific geometric arrangement.

[The role of hemorheologic changes in the pathogenesis of acute hemorrhagic necrotizing pancreatitis]

The hemorheologic alterations were studied in experimental acute hemorrhagic necrotizing pancreatitis (AHNP) which was induced by injection of 5% sodium taurocholate into the main pancreatic duct. The results showed that during the early stage of AHNP, all of hemorheologic parameters were significantly elevated, and continually increased at the rest intervals. The authors suggested that the blood viscosity and hematocrit increase, red blood cells tend to aggregate, and erythrocyte deformation decrease are the causation of pancreatic microcirculatory disturbances and promoting pancreatic progressive necrosis. After using low molecular dextran and Salvia miltiorrhizae, the hemorheologic alterations in AHNP were recovered, and the histologic observation improved. Our data indicate the hemorheologic disturbances is one of the key factors in the pathogenesis of AHNP.

Histopathology of cocaine hepatotoxicity. Report of four patients

Although cocaine is believed to be hepatotoxic for humans, the hepatic histopathology has been reported in only 1 patient. That patient had zone-1 necrosis. We have encountered 4 patients with liver injury secondary to cocaine use, 1 of whom died. The biopsies from two patients showed well-demarcated zone-3 necrosis identical to that seen with acetaminophen toxicity. The patient who died had necrosis of almost all hepatocytes as found at biopsy and autopsy. Biopsy was performed on another patient after resolution of the illness, and showed hyperplastic endoplastic reticulum but no necrosis. All patients had mild large- and small-droplet steatosis in surviving hepatocytes. Inflammation was mild. Drug screenings performed on all patients showed the presence of a cocaine metabolite and the absence of acetaminophen, alcohol, and other potential toxins. Patients typically had early marked increase and rapid decrease of serum aminotransferases, mild-to-moderate increase in prothrombin time, myoglobinuria, and moderate azotemia. The predominant pattern of zone-3 necrosis is similar to that reported of mice given cocaine.

Differential effects of a series of hydroxamic acid derivatives on 5-lipoxygenase and cyclooxygenase from neutrophils and 12-lipoxygenase from platelets and their in vivo effects on inflammation and anaphylaxis

The synthesis of a series of novel substituted hydroxamates has been described along with their profile of inhibitory activity against 5-lipoxygenase, 12-lipoxygenase, and cyclooxygenase enzymes. The structure--activity relationship suggests that future molecules could be designed to specifically inhibit one or more of these enzymes since there were definite differences in structure--activity relationships for these different enzymes. A representative number of these compounds have been tested in vivo and found to possess potent oral activity in a systemic anaphylaxis model mediated by leukotrienes and topical activity in an arachidonic acid induced inflammation model. One of these molecules, compound 20, demonstrated that a leukotriene antagonist pharmacophore can be modified such that it contains both antagonist activity and 5-lipoxygenase inhibitory activity.

Representations of ocular rotations in the cerebellar flocculus of the rabbit

The climbing fibres (CFs) of the rabbit flocculus that respond in a speed- and direction-selective manner to retinal image slip produced by eye rotations can be divided into three classes on the basis of the orientation of the rotation axis associated with their greatest modulation (the preferred axis). The similarity of the orientations of these axes to those of the eye rotation axes of the extraocular muscles suggests that a simple geometrical correspondence may exist between the eye rotation associated with the preferred axis of a given class of CFs and the eye rotation produced by activation of the Purkinje cells upon which that class of CFs synapse. To pursue this possibility, the axes of the eye rotations evoked by electrical microstimulation of the alert rabbit's flocculus were determined simultaneously for both eyes in three dimensions using two orthogonal search coils on each eye. A limited number of slow eye movement response patterns were found, and of these, two predominated. The most common response was a counterclockwise (CCW) rotation of the ipsilateral (left) eye around an axis close to the horizontal plane and at about 140 degrees posterior to the nose. The other predominant response was abduction of the ipsilateral eye. These two response patterns, together with the smaller conjugate components for the contralateral eye, are consonant with the orientations of the preferred CF axes. In addition, a clear CCW rotation of the contralateral (right) eye about its 135 degrees axis was also evoked from some stimulation sites. This response, which occurred either alone or as a component of an upward rotation about the nasal-occipital (roll) axis, is at variance with the orientations of the preferred CF axis. However, the latencies of the CCW contralateral 135 degrees component (80-140 ms) were greater than those of the CW contralateral 45 degrees component, the CCW ipsilateral 135 degrees component and the ipsilateral abduction component (8-48 ms). These latency differences may distinguish stimulation of Purkinje cells from stimulation of other neurones.

Balanced X;15 translocation 46,X,t(X;15)(q21;q23) associated with primary amenorrhea

Cytogenetic studies on a woman with primary amenorrhea showed an X;15 translocation, karyotype 46,X,t(X;15)(q21;q23). Fifteen percent of the buccal cells showed a normal-sized sex chromatin body. The normal X chromosome was uniformly inactivated. Many balanced X;15 translocations have been reported; however, breakpoints in our patient differ from those reported previously. This case also supports earlier evidence that ovarian development fails when the breakpoint of the X chromosome is in the region X q13-q25 or q13-q27.

The human androgen receptor: complementary deoxyribonucleic acid cloning, sequence analysis and gene expression in prostate

Androgenic hormones mediate their effects on male sex differentiation and development through a high affinity receptor protein. We report here cloning of the complete coding sequence of the human androgen receptor (hAR). By sequence homology hAR is a member of the nuclear receptor family, with closest sequence identity to the progesterone, mineralocorticoid, and glucocorticoid receptors. Regions of highest homology include the DNA-binding domain and a small region within the hydrophobic ligand-binding domain. Comparison of the deduced 919 amino acid sequence of hAR (98,999 mol wt) to the 902 amino acid sequence of rat AR (98,227 mol wt) reveals identical sequences in the DNA- and hormone-binding domains, with an overall homology of 85%. In human prostate, the major androgen receptor mRNA species is 10 kilobases while a less abundant mRNA is approximately 7 kilobases. Rabbit polyclonal antibodies were raised against a synthetic peptide from the N-terminal region of hAR. Immunocytochemical analysis of human prostate tissue demonstrated that AR is localized predominantly in nuclei of glandular epithelial cells.

Projections from the red nucleus and surrounding areas to the brainstem and spinal cord in the cat. An HRP and autoradiographical tracing study

HRP injections at the C2, T1 and S1 spinal levels and in the medullary lateral tegmental field revealed that the contralaterally projecting rubro-bulbospinal neurons are located not only in the caudal but also to a certain extent in the rostral red nucleus (RN). These RN projections are somatotopically organized. Neurons projecting to the sacral cord are located in the ventrolateral RN, those projecting to the upper part of the spinal cord lie in the dorsomedial RN and those projecting to the medullary lateral tegmentum were found in the dorsal portions of the RN. These last neurons are smaller than many of the other RN neurons. The HRP results also revealed that the RN does not project to the caudal raphe nuclei. The autoradiographical results confirmed the HRP findings. They further indicated that the contralateral RN projections to the caudal brainstem precerebellar nuclei (nucleus corporis pontobulbaris, lateral reticular nucleus, lateral cuneate nucleus) and the dorsal column nuclei are also somatotopically organized. This was also true for the RN projections to the dorsomedial and intermediate facial subnuclei and the caudal pontine and medullary lateral tegmental field. These areas receive afferents from mainly the dorsal portions of the RN. Regarding the RN projections to the spinal cord, the autoradiographical tracing results revealed somatotopically organized contralateral RN projections to laminae V, VI and VII. Moreover, a small but distinct RN projection to a dorsolaterally located group of motoneurons at the C8-T1 level was demonstrated. Ipsilaterally a minor projection to the cervical and upper thoracic lateral intermediate zone was observed. Finally, strong ipsilateral projections from the rostral mesencephalon to the inferior olive were seen. These projections were derived from various rostral mesencephalic areas, including the nucleus of Darkschewitsch, the nucleus accessorius medialis of Bechterew, the interstitial nucleus of Cajal and the area of the rostral interstitial nucleus of the medial longitudinal fasciculus. In the cat it was difficult to define which of the mesencephalic areas projecting to the inferior olive represented the parvocellular RN. A new subdivision of the RN is proposed based on its projections and not on the size of its cells. In this concept the first group is formed by the RN neurons projecting contralaterally to the caudal brainstem and spinal cord. The second group consists of RN neurons projecting to the inferior olive.(ABSTRACT TRUNCATED AT 400 WORDS)

Blinded comparison of cefuroxime to cefaclor for lower respiratory tract infections

Cefuroxime axetil was compared with cefaclor for the therapy for lower respiratory tract infections. Sixty-one patients were randomized to receive the following drug dosages: (1) cefuroxime axetil, 250 mg orally every 12 hours (21 patients); (2) cefuroxime axetil, 500 mg orally every 12 hours (21 patients); and (3) cefaclor, 500 mg orally every eight hours (19 patients). Of these 61 patients, 80% were male, with a mean age of 59.5 years; 56% had acute pneumonia, and the remainder had an acute bronchitis. Causative pathogens included typical respiratory tract pathogens. Overall, 23 of 27 patients with bronchitis were clinically cured at the end of therapy. Thirty-one of 34 pneumonias were clinically cured or improved at the end of therapy; the three pneumonia treatment failures occurred in the lower dose cefuroxime (n = 2) and cefaclor (n = 1) treatment groups. Overall, bacteriologic cure occurred in 86% of patients treated with 500 mg of cefuroxime axetil compared with 60% of cefaclor-treated patients. Adverse clinical effects were uncommon. From this study, it was concluded that cefuroxime given every 12 hours is at least as clinically efficacious as cefaclor; it is a new oral cephalosporin with pharmacologic and bacterial spectrum advantages over many older agents.

Supraspinal control of motoneurons innervating the striated muscles of the pelvic floor including urethral and anal sphincters in the cat

The nucleus of Onuf (ON) in mammals contains motoneurons innervating the pelvic floor muscles including the external urethral and anal sphincters. Recently, direct pathways from the dorsolateral pons to the ON, probably involved in supraspinal micturition control, have been reported (Holstege et al., 1986). Since the pelvic floor muscles are involved not only in micturition but also in various other functions (e.g., coughing, vomiting, defaecation, parturition), an attempt has been made to establish whether, in the cat, there exist other direct brainstem pathways to the ON motoneurons. Our results indicate that specific projections to the ON are derived from 3 different areas: (1) the ipsilateral paraventricular hypothalamic nucleus; (2) the ipsilateral caudal pontine lateral reticular formation; and (3) the contralateral caudal nucleus retroambiguus. More diffuse projections (to all motoneuronal cell groups in the spinal cord including the ON) are derived from (1) neurons in the area of the nucleus subcoeruleus in the dorsolateral pontine reticular formation, (2) the nucleus raphe pallidus, and (3) the ventral part of the medullary medial reticular formation. Possible functional implications of these pathways are discussed.

Eye diseases in the elderly in Singapore

Ocular disorders in the elderly have become more important because of increased longevity and the demand for good vision. Many serious ocular conditions are age-related and they include cataract, glaucoma, diabetic retinopathy and other retinal conditions. The most important ocular disorder is cataract which fortunately is curable with excellent results when a posterior chamber implant is inserted. Angle closure glaucoma is common in the elderly Singapore Chinese and can be effectively treated with microscopic peripheral iridectomy or trabeculectomy. Blindness from diabetic retinopathy can be prevented with argon laser photocoagulation. In most cases blindness is preventable with early diagnosis e.g. in glaucoma and diabetic retinopathy. Severe visual loss in the elderly requires careful explanation and compassion by doctors and social workers.

Afferent projections to the orbicularis oculi motoneuronal cell group. An autoradiographical tracing study in the cat

The motoneurons innervating the orbicularis oculi muscle from a subgroup within the facial nucleus, called the intermediate facial subnucleus. This makes it possible to study afferents to these motoneurons by means of autoradiographical tracing techniques. Many different injections were made in the brainstem and diencephalon and the afferent projections to the intermediate facial subnucleus were studied. The results indicated that these afferents were derived from the following brainstem areas: the dorsal red nucleus and the mesencephalic tegmentum dorsal to it; the olivary pretectal nucleus and/or the nucleus of the optic tract; the dorsolateral pontine tegmentum (parabrachial nuclei and nucleus of Kölliker-Fuse) and principal trigeminal nucleus; the ventrolateral pontine tegmentum at the level of the motor trigeminal nucleus; the caudal medullary medial tegmentum; the lateral tegmentum at the level of the rostral pole of the hypoglossal nucleus and the ventral part of the trigeminal nucleus and the nucleus raphe pallidus and caudal raphe magnus including the adjoining medullary tegmentum. These latter projections probably belong to a general motoneuronal control system. The mesencephalic projections are mainly contralateral, the caudal pontine and upper medullary lateral tegmental projections are mainly ipsilateral and the caudal medullary projections are bilateral. It is suggested that the different afferent pathways subserve different functions of the orbicularis oculi motoneurons. Interneurons in the dorsolateral pontine and lateral medullary tegmentum may serve as relay for cortical and limbic influences on the orbicularis oculi musculature, while interneurons in the ventrolateral pontine and caudal medullary tegmentum may take part in the neuronal organization of the blink reflex.

Anatomical observations on the afferent projections to the retractor bulbi motoneuronal cell group and other pathways possibly related to the blink reflex in the cat

In the cat retractor bulbi (RB) muscle reflexively retracts the eye ball into the orbit. This reflex action is called the nictitating membrane response which, together with the reflex contraction of the orbicularis oculi muscle, constitutes the blink reflex. The retractor bulbi (RB) motoneuronal nucleus is a small cell group located in the lateral tegmentum of the caudal pons, just dorsal to the superior olivary complex. The nucleus is identical to the accessory abducens nucleus and sends its fibers through the abducens nerve. Autoradiographical tracing results indicate that the RB nucleus receives some fibers from the principal and rostral spinal trigeminal nuclei and from the dorsal red nucleus and dorsally adjoining tegmentum. The same areas project to the intermediate facial subnucleus, containing motoneurons innervating the orbicularis oculi muscle. It is suggested that the trigeminal projections take part in the anatomical framework for the R1 component of the blink reflex. Two other brainstem areas i.e.: a portion of the caudal pontine ventrolateral tegmental field and the medullary medial tegmentum at the level of the hypoglossal nucleus were also found to project to the RB motoneuronal cell group and to the intermediate facial subnucleus. These projections were much stronger than those derived from the trigeminal nuclei and red nucleus. Moreover, the medullary premotor area projects not only to the blink motoneuronal cell groups but also to the pontine premotor area. It is suggested that both areas are involved in the R2 blink reflex component. The medullary blink premotor area receives afferents especially from oculomotor control structures in the reticular formation of the brainstem while the pontine blink premotor area receives afferents from the olivary pretectal nucleus and/or the nucleus of the optic tract and from the dorsal red nucleus and its dorsally adjoining area. Because the oculomotor control structures in the reticular formation (by way of the superior colliculus) and the red nucleus receive afferents from trigeminal nuclei, they may play an important role in tactually induced reflex blinking, while the pretectum could take part in the neuronal framework of the visually induced blink reflex.

Anatomical evidence that the pontine lateral tegmental field projects to lamina I of the caudal spinal trigeminal nucleus and spinal cord and to the Edinger-Westphal nucleus in the cat

Autoradiographical tracing results in the cat indicate that the lateral pontine tegmental field projects mainly contralaterally to the marginal layer of the spinal trigeminal nucleus, to laminae I and II and the lateral part of laminae V and VI of the spinal cord and the Edinger-Westphal nucleus. It is pointed out that the projections from the lateral pontine tegmentum are very similar to the ones derived from the Edinger-Westphal nucleus and that these two areas are reciprocally connected. It is postulated that both areas may play a role in supraspinal pain control.

Metastatic small cell carcinoma of the temporal bone. A case report

Metastatic tumours of the temporal bone are uncommon occurrences and a case is reported of a small cell carcinoma of the oesophagus with secondary involvement of the ear.

Mesencephalic projections to the facial nucleus in the cat. An autoradiographical tracing study

In 33 cats the projections of different parts of the mesencephalon to the facial nucleus were studied with the aid of the autoradiographical tracing method. The results indicate the existence of many different mesencephalo-facial pathways. The dorsomedial facial subnucleus, containing motoneurons innervating ear muscles, receives afferents from 4 different mesencephalic areas: a, the most rostral mesencephalic reticular formation; b, the nucleus of Darkschewitsch and/or the ventral part of the rostral PAG; c, the interstitial nucleus of Cajal and/or the mesencephalic tegmentum dorsomedial to the red nucleus. These areas project bilaterally by way of an ipsilateral medial tegmental pathway. The medial part of the deep tectum. This area projects bilaterally by way of the tecto-spinal tract. The lateral mesencephalic tegmentum close to the parabigeminal nucleus. This area projects mainly contralaterally by way of a separate contralateral lateral tegmental fiber bundle. The mesencephalic tegmentum just dorsolateral to the red nucleus and perhaps from the dorsolateral red nucleus itself. This area projects contralaterally by way of the rubrospinal tract. The intermediate facial subnucleus containing motoneurons innervating the muscle around the eye, receives afferents from two different mesencephalic areas: The dorsal part of the rostral as well as caudal red nucleus (but not from its caudal pole) and from the dorsally adjoining mesencephalic tegmentum including the area of the nucleus of Darkschewitsch and the interstitial nucleus of Cajal. These areas project contralaterally by way of the contralateral rubrospinal tract. The nucleus of the optic tract and/or the olivary pretectal nucleus. This area projects contralaterally by way of a contralateral medial tegmental pathway. The lateral and ventrolateral facial subnuclei containing motoneurons innervating the muscles around the mouth receive afferents from two different mesencephalic areas: The lateral part of the deep tectal layers. This area projects contralaterally by way of the tecto-spinal tract. The nucleus raphe dorsalis and perhaps the nucleus centralis superior. This area projects by way of the lateral tegmentum of caudal pons and medulla.

The organization of the gastric efferent projections in the brainstem of monkey: an HRP study

Topographic localization of neurons in the dorsal motor nucleus (DMN) of the vagus innervating the stomach and the extent of central decussation of its fibers were investigated in the monkeys after chronic unilateral cervical vagotomy. This study presents findings in regard to the non-topographic representation of the stomach in both DMN and lack of a well-defined decussation of its fibers in the brainstem of monkeys. Reported findings in the rat and cat vis-a-vis our own results in the monkey indicate species difference in the organization of efferent vagal gastric fibers. The evidence of a very small number of HRP-labeled cells in DMN on the vagotomized side after intervals of 2-36 weeks is being reported here, for what we believe to be the first time, and its significance has been discussed.