Role of ions and ion channels in the regulation of Atlantic croaker sperm motility

The effects of the osmolarity and ionic composition of the external media and ion-channel blockers on the induction of sperm motility in the marine teleost, Atlantic croaker (Micropogonias undulatus) were investigated. An in vitro sperm motility assay was developed to determine treatment effects on the percentage of motile sperm, sperm speed, and turning rate, using a computer-aided motion-analysis system. Maximum activation of sperm motility occurred in saline with an osmolarity of 680 mOs/kg. Potassium caused a decrease in the percentage of motile sperm, but only at high nonphysiological concentrations in the presence of high amounts of calcium. Calcium caused an increase in sperm velocity and turning rate. Percent motility was inhibited by the potassium-channel blockers, 4-aminopyridine and veratrine, the calcium-channel blockers, verapamil, diltiazem, and nifedipine; the sodium-channel blocker, amiloride, and the chloride-channel blocker, ethacrynic acid. In addition, the calcium-channel blockers caused a decrease in sperm velocity and turning rate. These results provide evidence for the role of potassium, calcium, and possibly sodium, and chloride ions in Atlantic croaker sperm motility. In addition, this study demonstrates that membrane-bound ion channels are involved in the motility of sperm from a marine teleost.

Operative risk and prognostic factors of typical bronchial carcinoid tumors

BACKGROUND

This study estimated operative risk and examined factors determining long-term survival after resection of typical carcinoid tumors.

METHODS

From 1976 to 1996, 139 consecutive patients (66 male and 73 female patients with a mean age of 47 +/- 15 years) underwent thoracotomy for typical carcinoid tumor. The tumors were centrally located in 102 patients (73.4%).

RESULTS

Radical resection was performed in 106 patients (7 pneumonectomies, 13 bilobectomies, and 86 lobectomies) and conservative resection in 33 (3 segmentectomies, 3 wedge resections, 20 sleeve lobectomies, and 7 sleeve bronchectomies). There were no postoperative deaths. Complications occurred in 19 patients (13.7%). The morbidity rate was not increased after bronchoplastic procedures (chi 2 = 0.033, not significant). Staging was pT1 in 107 patients (77.0%) and pT2 in 32 (23.0%); 13 patients (9.4%) had nodal metastases. Seventeen patients have died (12.2%), during follow-up, but only three deaths were related to the disease. The overall survival rate at 5, 10, and 15 years was estimated to be 92.4%, 88.3%, and 76.4%, respectively; estimated disease-free survival was 100% at 5 years and 91.4% at 10 and 15 years. Estimated survival of patients with lymph node metastasis was 100% at 5, 10, and 15 years. Univariate analysis failed to demonstrate any prognostic significance for sex, tumor size (T1 versus T2), tumor location (central versus peripheral), and type of resection.

CONCLUSIONS

These data confirm an excellent prognosis after complete resection of typical carcinoid tumors, including those with lymph node metastases. Parenchyma-saving resections should be preferred.

[Epilepsy and cancer]

INTRODUCTION

Seizures are common in patients presenting with intracranial tumors. Nevertheless, the incidence of cancer is not higher in patients with seizures. We attempted to summarize situations that can lead to the diagnosis or treatment of seizures in patients presenting with cancer.

CURRENT KNOWLEDGE AND KEY POINTS

Focal neurological signs on clinical examination when seizures occur for the first time in patients with cancer lead to brain imaging. As a result of recent advances in neuro-imaging techniques, the presence of a tumor is now more frequently observed in patients with seizures.

PERSPECTIVES AND FUTURE PROJECTS

As it may have irritating effects on the cerebral cortex, chemotherapy is able to either increase or induce seizures in patients presenting with cancer. Potential pharmacological interactions between antiepileptic and cytotoxic drugs thus require close surveillance in patients with cancer.

Perinuclear anti-neutrophil cytoplasmic antibodies in ulcerative colitis after restorative proctocolectomy do not correlate with the presence of pouchitis

BACKGROUND

Although perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) expression is strongly associated with ulcerative colitis, its relationship with the occurrence of pouchitis after restorative proctocolectomy is uncertain.

METHODS

Serum p-ANCA was assayed using both indirect immunofluorescence and enzyme-linked immunosorbent assay (ELISA) in 49 patients, of whom 25 had, and 24 had not, developed pouchitis. Control sera were obtained from 15 healthy volunteers.

RESULTS

By means of indirect immunofluorescence, p-ANCA was detected in 45.8% of patients without and in 48% with pouchitis (NS). Twenty-three (46.9%) of the 49 colitis patients were p-ANCA-positive, compared with none of the 15 controls (P < 0.01). By means of ELISA, p-ANCA positivity was present in 50% of patients without and in 68% with pouchitis (NS).

CONCLUSION

Whereas p-ANCA was associated with ulcerative colitis as compared with normal individuals, it was not associated with pouchitis. Thus it is unlikely to be a suitable pre-operative marker to identify those patients who will develop pouchitis.

Shared tumor antigens in colorectal carcinoma and neuroendocrine tumors

ND4 monoclonal antibody recognizes a tumor marker found on poorly differentiated colorectal cancer. We demonstrate its expression in 25% of gastrointestinal neuroendocrine tumors, which also express CEA in 37% of cases. As in colorectal cancer the ND4 marker is predominantly membrane bound in a colonic neuroendocrine tumor cell line, LCC-18 (p < 0.05). The ND4 marker is absent in a poorly differentiated colorectal cancer cell line that does not express CEA or other tumor antigens. Shed antigen in the serum of patients with neuroendocrine tumors is detected in only five of seven patients with the carcinoid syndrome and two of four of those without evidence of the syndrome. However, the reactivity was less in the patients with localized disease, and this test is unlikely to be of diagnostic utility in this group of patients. The sharing of this antigen in colorectal cancer and neuroendocrine tumors is not universal, but does support the common-cell progenitor theory for the origin of these tumors.

[Autosomal dominant nocturnal frontal lobe epilepsy]

Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a recently identified seizure disorder. The disease maps to the long arm of chromosome 20 and may be related in some families to a missense mutation in the neuronal nicotinic acetylcholine receptor alpha 4 subunit. We describe one of the first European family with ADNFLE, including five affected individuals spanning four generations. In the most severely affected subject, the onset was during the second month of life and persisted through adult life. Seizures were very frequent during infancy, although long-term evolution was relatively benign. Ictal video-EEG studies showed that attacks occurred in clusters during sleep and were partial seizures that were consistent with a frontal origin. Neuro-imaging was normal. Carbamazepine had a dramatic effectiveness. Although recognition of this syndrome is important for appropriate therapy and genetic counselling, underestimation of cases is likely: the disease was in our family perceived like a hereditary curse, and subsequently concealed, including to medical attention. Relationships with other partial familial epilepsies and with idiopathic benign partial epilepsies of childhood are discussed.

Huntingtin protein colocalizes with lesions of neurodegenerative diseases: An investigation in Huntington's, Alzheimer's, and Pick's diseases

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease associated with a CAG trinucleotide repeat expansion in a large gene on chromosome 4. The gene encodes the protein huntingtin with a polyglutamine tract encoded by the CAG repeat at the N-terminus. The number of CAG repeats in HD are significantly increased (36 to 120+) compared with the normal population (8-39). The pathological mechanism associated with the expanded CAG repeat in HD is not clear but there is evidence that polyglutamine is directly neurotoxic. We have immunolocalized huntingtin with an in-house, well-characterised, polyclonal antibody in HD, Alzheimer's disease (AD), and Picks disease (PiD) brains. Control brain tissue sections were from head injured and cerebral ischaemia cases. In HD, huntingtin was immunopositive in the surviving but damaged neurons and reactive astrocytes of the caudate and putamen. However, in AD and PiD the immunostaining was largely restricted to the characteristic intracellular inclusion bodies associated with the disease process in each case. In AD, huntingtin was localized only in the intracellular neurofibrillary tangles and dystrophic neurites within the neuritic amyloid plaques but not with the amyloid. In PiD, strongly positive huntingtin immunostaining was present within cytoplasmic Pick bodies. Our findings suggest huntingtin selectively accumulates in association with abnormal intracytoplasmic and cytoskeletal filaments of neurons and glia in neurodegenerative diseases such as HD, AD, and PiD. Cells in the CNS appear sensitive to damage by the aggregated, toxic levels of huntingtin and evidence of its interaction with neurofilaments could provide information about its potential role in the aetiology of HD.

Differential expression of alpha2,6-sialyltransferase in colon tumors recognized by a monoclonal antibody

It has been reported that alpha2,6-sialyltransferase (alpha2,6-ST; E.C. 2.4.99.1) activity is associated with cellular differentiation. To define its role in colon carcinoma differentiation, we have generated murine monoclonal antibodies (MAb) against alpha2,6-sialyltransferase. The MAb, designated 6B9 of IgM isotype, showed strong reactivity with the purified and crude alpha2,6-ST by ELISA and dot blot assays. Western blotting with MAb 6B9 identified purified alpha2,6-ST of MW 47 kDa and the same MW protein from rat and human liver extracts. The MAb also reacted with two other liver proteins of approximate MW 65 and 100 kDa. Immunoperoxidase studies with formalin-fixed paraffin-embedded tissues showed that MAb 6B9 reacts with liver tissues, the staining of hepatocytes was granular and cytoplasmic. There was a distinct pattern of zonal distribution of this enzyme in hepatocytes located particularly in the portal areas of the liver corresponding to zone 1. Normal colon (100%) and hyperplastic polyps (100%) showed very weak to no reactivity. Adenomas (100%) demonstrated moderate reactivity, while the poor (33%), moderate (100%) and well-differentiated (80%) colon adenocarcinomas showed strong reactivity. Results suggest that alpha2,6-ST is associated with the differentiation state of colon tumors.

Radiation inactivation of some food-borne pathogens in fish as influenced by fat levels

The influence of low (0.39-1.1%), medium (4.25%) and high (7.1-32.5%) fat levels in fish on radiation inactivation of four food-borne pathogens was investigated. Cells of Listeria monocytogenes 036, Yersinia enterocolitica F5692, Bacillus cereus and Salmonella typhimurium at logarithmic phase were inoculated in 10% fish homogenates and subjected to gamma irradiation at ice temperature (0-1 degree C) with doses ranging from 0.05 to 0.8 kGy. The radiation survival curves of L. monocytogenes and B. cereus were characterized by shoulders, while a tailing effect was depicted by cells of Y. enterocolitica and B. cereus. The D10 values in kGy calculated on the exponential part of the curve ranged from 0.2 to 0.3, 0.15 to 0.25, 0.1 to 0.15 and 0.09 to 0.1 for L. monocytogenes 036, B. cereus, Salm. typhimurium and Y. enterocolitica F5692, respectively. This order (D10) of radiation resistance of each organism was not affected by the fat content of the fish. Inoculated pack studies carried out separately with each pathogen in fatty (Indian sardine, 7.1%) and lean (Golden anchovy, 0.39%) fish showed no difference in their survival after exposure to 1 kGy and 3 kGy doses, which corroborated the above observation. The practical significance of these results in the application of the technology is discussed.

Open-lung biopsy in patients with acute respiratory distress syndrome

BACKGROUND

It has been suggested that fibrosis present during the fibroproliferative phase of acute respiratory distress syndrome (ARDS) can be treated by corticosteroids. However, neither clinical nor microbiologic criteria permit differentiation of this fibroproliferative phase from a nosocomial pneumonia. The aim of this observational case series was to evaluate the safety and utility of open-lung biopsy (OLB) performed in patients receiving ventilatory support who had persistent ARDS despite negative bacterial cultures.

METHODS

During a 4-yr period, 37 OLBs were performed in 36 of 197 patients receiving ventilatory support who had ARDS. The severity of ARDS was assessed by a lung injury score of 3.1 +/- 0.4 (mean +/- SD) and a median ratio of the partial pressure of oxygen (PaO2) to the fraction of inspired oxygen (FiO2) of 118 mmHg. Histologic examination; bacterial, fungal, and acid-fast staining; and cultures of the tissue sample were performed.

RESULTS

Fibrosis was present in only 41% of the lung specimens obtained by OLB. Only six patients received corticosteroids (17%). In 9 of the 15 patients with fibrosis, cytomegalovirus pneumonia precluded the use of corticosteroids. Histologic cytomegalovirus pneumonia was diagnosed in 18 cases. Histologic bacterial or mycobacterial pneumonia was diagnosed in five cases. No significant change in arterial blood gases was noted as linked to the biopsy procedure except an increase of the PaO2/FiO2 ratio. One pneumothorax was diagnosed on a chest roentgenogram 12 h after OLB. Only one patient required blood transfusion during the 48-h period after OLB (for an hemothorax). Five patients had moderate air leaks from operative chest tubes for 2-10 days.

CONCLUSIONS

Open lung biopsy appeared to be a useful and acceptably safe diagnostic technique in patients with ARDS. It permitted the diagnosis of unexpected cytomegalovirus pneumonia.

Natural rubber-latex allergy in patients not intensely exposed

Immediate-type allergy to natural rubber latex (NRL) is common in highly exposed groups, particularly in health-care workers and patients with spina bifida. The occurrence of NRL allergy was investigated in subjects not belonging to such risk groups. A total of 493 patients presenting with various diseases for allergologic evaluation was studied. A questionnaire-based history was taken, skin prick tests with NRL milk and common aeroallergens were done, and NRL-specific serum IgE antibodies were measured. A total of 317 subjects (64.3%) was atopic. There were skin prick test reactions to NRL in 80 (16.2%) and NRL-specific IgE in the serum in 79 (16.0%) subjects; both were found in 25 patients (5.1%). Altogether, NRL sensitization was found in 134 patients (27.2%). By history and/or challenge tests, 13 subjects (2.6%) were diagnosed as having clinically relevant NRL allergy. In five of these, anaphylactic reactions had occurred during dental procedures, and in four during general anesthesia; 10 subjects reported immediate-type reactions to NRL products in daily life. All patients with clinically relevant NRL allergy had a skin prick test reaction to NRL milk (sensitivity 100%). Nine had specific IgE antibodies in the serum (sensitivity 69.2%); respective specificity was 86.0% or 85.4%. Nine of the 13 patients (69.2%) with NRL allergy were atopic. Despite exclusion of those at risk, many patients had clinically relevant allergy to NRL, and many of these had had severe reactions. NRL allergy is an important health issue also beyond the known risk groups.

Early views of the martian surface from the Mars Orbiter Camera of Mars Global Surveyor

High-resolution images of the martian surface at scales of a few meters show ubiquitous erosional and depositional eolian landforms. Dunes, sandsheets, and drifts are prevalent and exhibit a range of morphology, composition (inferred from albedo), and age (as seen in occurrences of different dune orientations at the same location). Steep walls of topographic depressions such as canyons, valleys, and impact craters show the martian crust to be stratified at scales of a few tens of meters. The south polar layered terrain and superposed permanent ice cap display diverse surface textures that may reflect the complex interplay of volatile and non-volatile components. Low resolution regional views of the planet provide synoptic observations of polar cap retreat, condensate clouds, and the lifecycle of local and regional dust storms.

CD14 and lipopolysaccharide binding protein expression in a rat model of alcoholic liver disease

Lipopolysaccharide-binding protein (LBP) and CD14 play key intermediary roles in the activation of cells by endotoxin. As endotoxin has been postulated to participate in promoting pathological liver injury in alcoholic liver disease, we investigated the role of LBP and CD14 in alcoholic liver injury. Rats were fed intragastrically ethanol or dextrose and either medium-chain triglycerides, corn oil, or fish oil for 4 weeks. Kupffer cells, endothelial cells, and hepatocytes were isolated. LBP and CD14 mRNA levels were measured in liver and individual cell types. The highest levels of LBP and CD14 mRNA levels in the liver were found in the fish oil/ethanol group, which was also the group with the greatest degree of pathological injury and inflammation. CD14 mRNA levels were also significantly elevated in groups fed unsaturated fatty acids with dextrose. CD14 expression was localized to the Kupffer cells and LBP expression to the hepatocytes. Expression of CD14 mRNA was also found in nonmyeloid cells in the two experimental groups (fish oil/ethanol and corn oil/ethanol) that had liver necrosis and inflammation. Our results suggest that enhanced LBP and CD14 expression correlates with the presence of pathological liver injury in alcoholic liver injury. Furthermore, unsaturated fatty acids may prime cells to respond to endotoxin by enhancing CD14 expression.

Clinical patterns and trends of outcome of elderly patients with bronchogenic carcinoma

OBJECTIVE

To investigate the clinical characteristics and determinants of operative mortality and long-term survival of elderly patients submitted to pulmonary resection for intended cure of lung cancer.

METHODS

Retrospective analysis of 500 consecutive pulmonary resections performed in patients aged over 70 years from 1975 to 1996. Predictors of in-hospital mortality were identified by univariate and multivariate analyses. Determinants of long-term outcome were investigated in all survivors, with no patient being lost to follow-up.

RESULTS

Mean age was 74 +/- 3 years (maximum: 90), and 36 patients were octogenarians. The sex-ratio M:F was 5:3. History of combined cardiovascular or previous neoplastic disease was noted in 193 and 63 patients, respectively. The predominant histology was squamous cell carcinoma (n = 243), with a significantly higher incidence in male than in female. Most patients received standard procedures, while 103 patients underwent extended resections for tumors involving the mediastinum (n = 44), the chest wall (n = 33), the carina (n = 2) or had a sleeve resection of the main bronchus (n = 24). Procedures were considered to be complete and curative in 459 patients, among whom 294 had a stage I disease. There were 37 (7.4%) in-hospital deaths. Mortality rates following pneumonectomy, bilobectomy, lobectomy and lesser resection were 11:136, 4:34, 22:291, and 0:39, respectively. Age, male gender, hypertension, low FEV1 and extended procedure were identified as independent predictors of early mortality. Overall survival rates were 33.7 and 12% at 5 and 10 years, respectively. Multivariate analysis demonstrated that the disease stage was the main prognosticator. During the follow-up period, cancer recurrence (n = 183; 39.5%) or second primary lung cancer (n = 20; 4.3%) occurred in 203 patients, among whom 18 (9%) had a second lung resection. Carcinoma in other systems occurred in 25 patients (5.3%), and major cardiovascular event in 51 (11%).

CONCLUSIONS

Male and squamous cell carcinoma are characteristic of elderly patients with resected lung cancer. Operative mortality is acceptable for standard resection, and survival figures are concordant with those reported in other series which include younger patients.

Mapping of dopamine D3 receptor binding site by pharmacological characterization of mutants expressed in CHO cells with the Semliki Forest virus system

Nine mutants and the wild-type human dopamine D3 receptor were expressed at high levels in BHK and CHO cells using the Semliki Forest virus system and were analysed for receptor binding with several structurally different dopamine D3 ligands. The mutation His349Leu showed a significant decrease in pKi values for raclopride, dopamine and GR218231, but an increase in affinity for GR99841. Thr369Val had an increase in pKi for both GR99841 and 7-OH-DPAT. The receptor modelling based on sequence alignment with bacteriorhodopsin indicated that Thr369 and His349 are located on the inside of the ligand binding pocket and the effect of the mutagenesis was therefore expected. The change in binding affinity for Thr369Val could be due to the location in the transmembrane domain VII close to the aspartate residue in domain III, the postulated counter ion for dopamine.

Carbamazepine in the treatment of neuroleptic malignant syndrome

BACKGROUND

Neuroleptic malignant syndrome (NMS) is a potentially lethal adverse effect to neuroleptic drugs.

METHODS

We report on 2 cases where NMS dramatically improved with carbamazepine. Incidental removal and reapplication of carbamazepine attests to its effectiveness for this condition.

RESULTS

A 34-year-old woman treated for a major depressive disorder experienced NMS with a phenothiazine. Her condition dramatically improved in 8 hours after she was administered carbamazepine. Since carbamazepine was discontinued, NMS recurred in 10 hours and remitted anew within less than 24 hours after reintroduction. A 31-year-old woman experiencing a schizoaffective disorder displayed NMS with aphenothiazine and a butyrophenone. NMS completely resolved within 8 hours after she was administered carbamazepine. NMS recurred within 12 hours after carbamazepine discontinuation.

CONCLUSIONS

These data thus account for a cause-effect relationship between carbamazepine administration and NMS relief, and argue against the neuroleptic withdrawal to be responsible by itself for NMS relief.

Magnetic resonance angiography of giant intracranial aneurysms

3D time-of-flight magnetic resonance angiography (3D TOF MRA) and 2D MRA with presaturation were evaluated in 18 patients with 21 giant intracranial aneurysms. 3D TOF MRA gave optimal images of proximal unruptured and nonthrombosed aneurysms. 2D MRA with presaturation was more informative in cases of distal, haemorrhagic or thrombosed aneurysms and in assessment of their components (thrombus, haemorrhage, patent residual lumen).

Evidence for a subsurface ocean on Europa

Ground-based spectroscopy of Jupiter's moon Europa, combined with gravity data, suggests that the satellite has an icy crust roughly 150 km thick and a rocky interior. In addition, images obtained by the Voyager spacecraft revealed that Europa's surface is crossed by numerous intersecting ridges and dark bands (called lineae) and is sparsely cratered, indicating that the terrain is probably significantly younger than that of Ganymede and Callisto. It has been suggested that Europa's thin outer ice shell might be separated from the moon's silicate interior by a liquid water layer, delayed or prevented from freezing by tidal heating; in this model, the lineae could be explained by repetitive tidal deformation of the outer ice shell. However, observational confirmation of a subsurface ocean was largely frustrated by the low resolution (>2 km per pixel) of the Voyager images. Here we present high-resolution (54 m per pixel) Galileo spacecraft images of Europa, in which we find evidence for mobile 'icebergs'. The detailed morphology of the terrain strongly supports the presence of liquid water at shallow depths below the surface, either today or at some time in the past. Moreover, lower-resolution observations of much larger regions suggest that the phenomena reported here are widespread.

Episodic plate separation and fracture infill on the surface of Europa. Galileo Imaging Team

Images obtained by the Voyager spacecraft revealed dark, wedge-shaped bands on Europa that were interpreted as evidence that surface plates, 50-100 km across, moved and rotated relative to each other. This implied that they may be mechanically decoupled from the interior by a layer of warm ice or liquid water. Here we report similar features seen in higher resolution images (420 metres per pixel) obtained by the Galileo spacecraft that reveal new details of wedge-band formation. In particular, the interior of one dark band shows bilateral symmetry of parallel lineaments and pit complexes which indicates that plate separation occurred in discrete episodes from a central axis. The images also show that this style of tectonic activity involved plates < 10 km across. Although this tectonic style superficially resembles aspects of similar activity on Earth, such as sea-floor spreading and the formation of ice leads in polar seas, there are significant differences in the underlying physical mechanisms: the wedge-shaped bands on Europa most probably formed when lower material (ice or water) rose to fill the fractures that widened in response to regional surface stresses.