A prospective randomized controlled trial comparing early postoperative complications in patients undergoing loop colostomy with and without a stoma rod

AIM

A stoma rod or bridge has been traditionally placed under the bowel loop while constructing a loop colostomy. This is believed to prevent stomal retraction and provide better faecal diversion. However, the rod can cause complications such as mucosal congestion, oedema and necrosis. This single-centre prospective randomized controlled trial compared outcomes after creation of loop colostomy with and without a supporting stoma rod. The primary outcome studied was stoma retraction rate; other stoma-related complications were studied as secondary outcomes.

METHOD

One hundred and fifty-one patients were randomly allotted to one of two arms, colostomy with or without a supporting rod. Postoperative complications such as retraction, mucocutaneous separation, congestion and re-exploration for stoma-related complications were recorded.

RESULTS

There was no difference in the stoma retraction rate between the two arms (8.1% in the rod arm and 6.6% in the no-rod arm; P = 0.719). Stomal necrosis (10.7% vs 1.3%; P = 0.018), oedema (23% vs 3.9%; P = 0.001), congestion (20.3% vs 2.6%; P = 0.001) and re-admission rates (8.5% vs 0%; P = 0.027) were significantly increased in the arm randomized to the rod.

CONCLUSION

The stoma rod does not prevent stomal retraction. However, complication rates are significantly higher when a stoma rod is used. Routine use of a stoma rod for construction of loop colostomy can be avoided.

Perthes' disease in the adolescent

We studied the natural history of Perthes' disease in 62 children in whom the onset of symptoms was in adolescence. Three patterns of disease were noted, namely, late-onset pattern, segmental collapse, or destructive with failure of revascularisation. In the late-onset pattern, the disease followed the sequence of healing seen in younger children, but adequate epiphyseal remodelling did not occur. Consequently, the femoral head was never spherical after revascularisation. With segmental collapse, early and irreversible collapse of part of the epiphysis occurred with gross deformation of the femoral head. The destructive pattern was characterised by a failure of revascularisation and repair of the avascular epiphysis. The radiological outcome was poor in all three patterns. The poorest clinical results were found in the destructive type which was frequently associated with incapacitating pain requiring arthrodesis or excision arthroplasty within three years of onset of the disease.

Perthes’ disease in the adolescent

We studied the natural history of Perthes’ disease in 62 children in whom the onset of symptoms was in adolescence.

Three patterns of disease were noted, namely, late-onset pattern, segmental collapse, or destructive with failure of revascularisation. In the late-onset pattern, the disease followed the sequence of healing seen in younger children, but adequate epiphyseal remodelling did not occur. Consequently, the femoral head was never spherical after revascularisation. With segmental collapse, early and irreversible collapse of part of the epiphysis occurred with gross deformation of the femoral head. The destructive pattern was characterised by a failure of revascularisation and repair of the avascular epiphysis.

The radiological outcome was poor in all three patterns. The poorest clinical results were found in the destructive type which was frequently associated with incapacitating pain requiring arthrodesis or excision arthroplasty within three years of onset of the disease.

Oligomerization of dopamine and serotonin receptors

Until recently, it has largely been assumed that G protein-coupled receptors (GPCRs) function as monomeric entities. However, over the past few years, we and others have documented that GPCRs can form dimers and oligomers, leading to a re-evaluation of the mechanisms thought to mediate GPCR function. Despite the growing number of investigations into dimerization, little is known about the structural basis of receptor-receptor interactions and the functional consequences of dimer formation. Here, we present a brief review of some insights we have gained into the dimerization of dopamine and serotonin receptors. We have demonstrated that agonist-regulated trafficking is identical for receptor monomers and dimers, however, agonist treatment appears to stabilise the receptor oligomers. An investigation of the structural assembly between receptors involved in dimerization showed that there are several sites of interaction including hydrophobic transmembrane domain interactions and intermolecular disulphide bonds. We have also examined receptor hetero-oligomerization and demonstrated the potential for novel functions as a result of these associations. Finally, as a result of these observations, we have been able to present evidence that GPCRs function as oligomers in the cell.

Clausa, a tomato mutant with a wide range of phenotypic perturbations, displays a cell type-dependent expression of the homeobox gene LeT6/TKn2

Class I knox genes play an important role in shoot meristem function and are thus involved in the ordered development of stems, leaves, and reproductive organs. To elucidate the mechanism underlying the expression pattern of these homeobox genes, we studied a spontaneous tomato (Lycopersicon esculentum) mutant that phenotypically resembles, though is more extreme than, transgenic plants misexpressing class I knox genes. This mutant was found to carry a recessive allele, denoted clausa:shootyleaf (clau:shl)-a newly identified allele of clausa. Mutant plants exhibited abnormal leaf and flower morphology, epiphyllus inflorescences, fusion of organs, calyx asymmetry, and navel-like fruits. Analysis by scanning electron microscopy revealed that such fruits carried ectopic ovules, various vegetative primordia, as well as "forests" of stalked glandular trichomes. In situ RNA hybridization showed a peculiar expression pattern of the class I knox gene LeT6/TKn2; expression was restricted to the vascular system and palisade layer of mature leaves and to the inner part of ovules integuments. We conclude that CLAUSA regulates various aspects of tomato plant development, at least partly, by rendering the LeT6/TKn2 gene silent in specific tissues during development. Considering the expression pattern of LeT6/TKn2 in the clausa mutant, we suggest that the control over a given homeobox gene is maintained by several different regulatory mechanisms, in a cell type-dependent manner.

Oligomerization of mu- and delta-opioid receptors. Generation of novel functional properties

The existence of dimers and oligomers for many G protein-coupled receptors has been described by us and others. Since many G protein-coupled receptor subtypes are highly homologous to each other, we examined whether closely related receptors may interact with each other directly and thus have the potential to create novel signaling units. Using mu- and delta-opioid receptors, we show that each receptor expressed individually was pharmacologically distinct and could be visualized following electrophoresis as monomers, homodimers, homotetramers, and higher molecular mass oligomers. When mu- and delta-opioid receptors were coexpressed, the highly selective synthetic agonists for each had reduced potency and altered rank order, whereas endomorphin-1 and Leu-enkephalin had enhanced affinity, suggesting the formation of a novel binding pocket. No heterodimers were visualized in the membranes coexpressing mu- and delta-receptors by the methods available. However, hetero-oligomers were identified by the ability to co-immunoprecipitate mu-receptors with delta-receptors and vice versa using differentially epitope-tagged receptors. In contrast to the individually expressed mu- and delta-receptors, the coexpressed receptors showed insensitivity to pertussis toxin and continued signal transduction, likely due to interaction with a different subtype of G protein. In this study, we provide, for the first time, evidence for the direct interaction of mu- and delta-opioid receptors to form oligomers, with the generation of novel pharmacology and G protein coupling properties.

Inhibition of cell surface expression by mutant receptors demonstrates that D2 dopamine receptors exist as oligomers in the cell

Numerous mutant G protein-coupled receptors with diminished or no function have been described that are naturally occurring or that are the product of gene manipulation. It has largely been assumed that receptor mutants do not affect the function of the wild-type receptor; however, the occurrence of G protein-coupled receptor dimerization suggests the possibility that an intermolecular interaction between mutant and wild-type receptors can occur. We have shown previously that the D2 dopamine receptor (D2DR) exists as dimers in cell lines and brain tissue. In this study, we demonstrated that mutant D2DR can modulate the function of the wild-type D2DR. While attempting to elucidate the structure of the D2DR dimer, we demonstrated that nonfunctional D2DR substitution and truncation mutants antagonized wild-type D2DR function. Furthermore, from analyses of this interaction between the receptor mutants and the D2DR, using photoaffinity labeling, we provide evidence that the D2DR is oligomeric in the cell.

Nerve and muscle disorders and their sequelae

A number of diseases of the nervous system, especially upper neuron lesions, produce ankle and foot deformities. Such deformities can be the single most important reason why some patients become nonambulatory. This article reviews the impact of upper motor neuron lesions such as traumatic brain injury, stroke, multiple sclerosis, neurodegenerative disorders, and low motor neuron lesions such as peripheral nerve injury, neuropathy, entrapment syndromes, and muscle diseases. This article also reviews diagnostic tests including EMG and nonsurgical management.

Packet classification using tuple space search

Routers must perform packet classification at high speeds to efficiently implement functions such as firewalls and QoS routing. Packet classification requires matching each packet against a database of filters (or rules), and forwarding the packet according to the highest priority filter. Existing filter schemes with fast lookup time do not scale to large filter databases. Other more scalable schemes work for 2-dimensional filters, but their lookup times degrade quickly with each additional dimension. While there exist good hardware solutions, our new schemes are geared towards software implementation.We introduce a generic packet classification algorithm, called Tuple Space Search (TSS) . Because real databases typically use only a small number of distinct field lengths, by mapping filters to tuples even a simple linear search of the tuple space can provide significant speedup over naive linear search over the filters. Each tuple is maintained as a hash table that can be searched in one memory access. We then introduce techniques for further refining the search of the tuple space, and demonstrate their effectiveness on some firewall databases. For example, a real database of 278 filters had a tuple space of 41 which our algorithm prunes to 11 tuples. Even as we increased the filter database size from 1K to 100K (using a random two-dimensional filter generation model), the number of tuples grew from 53 to only 186, and the pruned tuples only grew from 1 to 4. Our Pruned Tuple Space search is also the only scheme known to us that allows fast updates and fast search times. We also show a lower bound on the general tuple space search problem, and describe an optimal algorithm, called Rectangle Search , for two-dimensional filters.

Epoetin alpha prevents anaemia and reduces transfusion requirements in patients undergoing primarily platinum-based chemotherapy for small cell lung cancer

Anaemia commonly occurs in cancer patients receiving chemotherapy, often necessitating blood transfusion. This multicentre study was designed to evaluate the efficacy and safety of epoetin alpha in preventing the decline in haemoglobin (Hb) level, and to determine whether the transfusion requirement could be reduced, in patients receiving 4-6 cycles of primarily platinum-based combination cyclic chemotherapy for small cell lung cancer (SCLC). A total of 130 non-anaemic SCLC patients were randomized to receive no additional treatment (n = 44), epoetin alpha 150 IU kg(-1) subcutaneously (s.c.) three times a week (n = 42) or 300 IU kg(-1) s.c. three times a week (n = 44). Reductions in epoetin alpha dosage were made during the study if Hb level increased to >15 g dl(-1). The mean weekly dosage was 335 and 612 IU kg(-1), respectively, in the two active treatment groups. Significantly fewer (P < 0.05) epoetin alpha-treated patients experienced anaemia (Hb < 10 g dl(-1)) during the course of chemotherapy (300 IU kg(-1), 39%; 150 IU kg(-1), 48%; untreated, 66%). This was reflected in the significantly lower number of treated patients transfused [300 IU kg(-1), 20% (P< 0.001); 150 IU kg(-1), 45% (P< 0.05); untreated, 59%]. Epoetin alpha was well-tolerated, and there was no evidence of sustained, clinically significant, hypertension. In summary, epoetin alpha is effective and well-tolerated in maintaining Hb level and reducing transfusion requirement in patients undergoing cyclic chemotherapy for SCLC.

Medical education: Nasal endoscope and you

Although much has been written about the surgical technique of functional endoscopic sinus surgery, for sinusitis and nasal polyposes, the other uses of the nasal endoscope has not been mentioned, Seven hundred and twenty five patients have undergone endoscopic nasal office evaluations and subsequent functional endoscopic sinus surgery for various indications in our unit from December 1990 to September 1994. Though most of the surgeries were for nasal polyposes and sinusitis, we have used the scope for various other indications.

A transmembrane domain-derived peptide inhibits D1 dopamine receptor function without affecting receptor oligomerization

In this study, we show that a peptide based on the sequence of transmembrane domain 6 of the D1 dopamine receptor (D1DR) specifically inhibited D1DR binding and function, without affecting receptor oligomerization. It has been shown that an analogous peptide from the beta2-adrenergic receptor disrupted dimerization and adenylyl cyclase activation in the beta2-adrenergic receptor (Hebert, T. E., Moffett, S., Morello, J. P., Loisel, T. P., Bichet, D. G., Barret, C., and Bouvier, M. (1996) J. Biol. Chem. 271, 16384-16392). Treatment of D1DR with the D1DR transmembrane 6 peptide resulted in a dose-dependent, irreversible inhibition of D1DR antagonist binding, an effect not seen in D1DR with peptides based on transmembrane domains of other G protein-coupled receptors. Incubation with the D1DR transmembrane 6 peptide also resulted in a dose-dependent attenuation of both dopamine-induced [35S]guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) binding and receptor-mediated dopamine stimulation of adenylyl cyclase activity. Notably, GTPgammaS binding and cAMP production were reduced to levels below baseline, indicating blockade of ligand-independent, intrinsic receptor activity. Immunoblot analyses of the D1DR revealed the receptor existed as monomers, dimers, and higher order oligomers and that these oligomeric states were unaffected after incubation with the D1DR transmembrane 6 peptide. These findings represent the first demonstration that a peptide based on the transmembrane 6 of the D1DR may represent a novel category of noncompetitive D1DR antagonists.

Fast and scalable layer four switching

In Layer Four switching, the route and resources allocated to a packet are determined by the destination address as well as other header fields of the packet such as source address, TCP and UDP port numbers. Layer Four switching unifies firewall processing, RSVP style resource reservation filters, QoS Routing, and normal unicast and multicast forwarding into a single framework. In this framework, the forwarding database of a router consists of a potentially large number of filters on key header fields. A given packet header can match multiple filters, so each filter is given a cost, and the packet is forwarded using the least cost matching filter .In this paper, we describe two new algorithms for solving the least cost matching filter problem at high speeds. Our first algorithm is based on a grid-of-tries construction and works optimally for processing filters consisting of two prefix fields (such as destination-source filters) using linear space. Our second algorithm, cross-producting, provides fast lookup times for arbitrary filters but potentially requires large storage. We describe a combination scheme that combines the advantages of both schemes. The combination scheme can be optimized to handle pure destination prefix filters in 4 memory accesses, destination-source filters in 8 memory accesses worst case, and all other filters in 11 memory accesses in the typical case.

Tuberculosis incidence in Northern Ireland and the Republic of Ireland--a collaborative study

We examined the incidence of tuberculosis in the Republic of Ireland and Northern Ireland for 1991 using the Census of Population for both jurisdictions, data from a National Survey of Tuberculosis for 1991 for the Republic and examination of nominal notification data for Northern Ireland. We showed that there is a significantly higher incidence of TB in the Republic of Ireland. More cases were reported (p < 1.0 x 10(-7)) as were more bacteriologically proven cases (p < 1.0 x 10(-7)). The difference was true for each of the following age groups (< 15 years, 15-35 years, 35-54 years and > 55 years) but it is noteworthy that areas in the Republic which make use of neonatal BCG vaccine did not have a significantly different rate of tuberculosis for individuals less than 15 years (p = 0.34) compared to Northern Ireland.

Tuberculosis in health service employees in Northern Ireland

Tuberculosis can be transmitted from patients to health care workers. However, where the incidence of tuberculosis is low, and good infection control practices exist, the risk of health care workers acquiring the disease is likely to be small. The objective of this study was to determine the rate of notification of tuberculosis in health care workers in Northern Ireland compared with the general population. Information from the statutory tuberculosis notification forms for the period 1982-1991 was entered on to a computer database. Those patients involved in health care occupations were identified and age and sex standardized incidence rates were calculated. The overall notification rate for tuberculosis was 7.4 cases per 100,000 of general population. There was no significant increase in notification of tuberculosis among health care workers [standardized incidence ratio: 126% (95% CI 91-170)]. No cases were diagnosed as a result of screening methods performed during employment. It was concluded that health care workers in Northern Ireland did not have a significantly increased incidence of tuberculosis compared with the general population over the 10-year period studied. This suggests that the risk of transmission from patients to health care workers is negligible in the setting of a low general incidence of tuberculosis and good infection control practice. Under these circumstances, the present findings support the cessation of routine screening of health care workers.

Resistance of the dopamine D2L receptor to desensitization accompanies the up-regulation of receptors on to the surface of Sf9 cells

Dopamine D2 receptor agonists are commonly used in the control of PRL-secreting adenomas, and the sensitivity of dopamine agonists during long term therapy is exquisite. However, the molecular mechanisms responsible for the maintenance of this cellular sensitivity to dopamine agonists remain poorly understood. In the present study, we examined the agonist-induced regulation of the human D2L receptor expressed to a specific activity of approximately 1 pmol receptor/mg protein in Sf9 insect cells. Treatment of D2L receptor-expressing cells with dopamine for up to 3 h resulted in no detectable change in the ligand-binding properties of the receptor and a approximately 120-fold reduction in the potency, but not the efficacy, of D2L receptors to mediate dopamine inhibition of forskolin-stimulated adenylyl cyclase activity. This resistance of the D2L receptor to agonist-induced desensitization was accompanied by a approximately 28% translocation of intracellular D2L receptors to the cell surface, as quantified by cellular fractionation and radioligand binding and visualized by whole cell immunocytochemical staining and confocal microscopy. Immunoblot analysis of the P2 membrane fraction revealed that surface D2L receptors comprised monomers and dimers. Treatment of D2L receptor-expressing cells with the protein synthesis inhibitor cycloheximide significantly reduced the basal expression level of receptors, but did not block the agonist-induced up-regulation of receptors. Longer periods of dopamine exposure for 24 h brought about a small increase in surface receptor density. However, when these studies were conducted in the presence of cycloheximide, receptor density was marginally reduced, suggesting that receptor synthesis accounts for the maintenance of cellular receptor density under these conditions. We conclude that the resistance of the D2L receptor-coupled adenylyl cyclase system to agonist-induced desensitization is attributed to the up-regulation of surface receptors after the translocation of existing intracellular receptors and de novo receptor synthesis.

Autonomic dysfunction associated with locked-in syndrome in a child

This is a report of a young boy with the unusual combination of autonomic dysfunction with locked-in syndrome following multiple shunt revisions for hydrocephalus. A review of the literature on autonomic dysfunction syndrome and the complex clinical picture of the combined syndromes in a pediatric patient are discussed. The marked effectiveness of treatment with carbidopa/levodopa over bromocriptine for both syndromes is noted.

Hearing anomalies following radiation therapy for head and neck cancers

Ionizing radiation used for the treatment of head and neck tumors affected epithelial and connective tissue. Epithelial lining of the middle ear mucosa desquamated, when exposed to conventional dose of radiation. Mucosa becomes oedematous which subsequently lead to formation and collection of sterile fluid within middle ear cavity and thus producing radiation otitis media with conductive deafness. Radiation induced changes in the structure surrounding the end organs of hearing such as vascular and connective tissue alterations which later eventually could affect the end organ leading to perceptive type of hearing loss as a result of chronic anoxia to end organ.

Use of Sinemet in locked-in syndrome: a report of two cases

Locked-in syndrome describes a neurological condition usually associated with infarction of the ventral pons. Such patients are diagnosed with quadriplegia, lower cranial nerve paralysis, and mutism. The patient is alert but communication is severely limited and usually is accomplished by blinking or using vertical eye movements. The rehabilitative management of locked-in syndrome has consisted of preventative and supportive measures. In this study we report two cases of locked-in syndrome which were treated successfully with Sinemet (DuPont Pharmaceuticals, Wilmington, DE). Even though the exact neuropharmacological mechanism is unclear, the dramatic improvement in these cases, as well as in one other published case report, dictates that use of Sinemet should be considered in the management of locked-in syndrome.

Effect of propylthiouracil treatment on NADPH-cytochrome P450 reductase levels, oxygen consumption and hydroxyl radical formation in liver microsomes from rats fed ethanol or acetone chronically

The antithyroid drug propylthiouracil (PTU) has been shown previously to reduce hepatic oxygen utilization and to protect the liver from ethanol-induced injury. The present study examined the effect of PTU on hepatic microsomal oxygen consumption and on the activities of NADPH-cytochrome P450 reductase (CYP-reductase) and cytochrome P4502E1 (CYP2E1) in rats receiving ethanol or acetone chronically. Liver microsomes from rats treated with ethanol for 29 days displayed increases in (i) O2 consumption (70%), (ii) hydroxyl radical (.OH) production (49%) and (iii) ethanol oxidation (50%). Microsomal CYP2E1 levels were increased markedly by chronic ethanol administration, while CYP-reductase was affected marginally, but not significantly (P = 0.06). Chronic treatment with acetone for 14 days, produced similar effects, except that .OH production was not enhanced. Administration of PTU (25 mg/kg/day) to ethanol- or acetone-fed rats, for 10 and 14 days, respectively, led to a marked reduction in the levels and activity of CYP-reductase, and to a decrease in the rates of microsomal O2 consumption, .OH production and ethanol oxidation, but did not lower the levels of CYP2E1 or the metabolism of the CYP2E1 substrate N,N-nitrosodimethylamine. These data suggest that the ability of PTU to protect the liver from ethanol-induced injury may be due to a reduction in the levels of CYP-reductase, thereby minimizing the enhancement of microsomal oxygen consumption and free radical generation associated with ethanol-induced CYP2E1 activity.

Replantation and amputation of digits: user analysis

There now is extensive literature on the survival and function of replanted digits but little on the function of the hand as a whole after this procedure, as opposed to amputations. In our review of the literature, we found almost nothing on the patient's perspective of the outcome from these procedures. This study was a preliminary attempt to study the outcome of these procedures from the patient's viewpoint. There were nine replantations and ten amputations of digits in the final study groups, based on medical record screening and patient questionnaires. Multivariate analysis, Hotelling T2, was used to test significant differences between the variables in the two groups. Significant differences were found in the two groups. The replantations had longer lengths of treatment and therapy, were off work longer (34.4 wk of therapy and 40 wk off work), and rated their function poorer compared with amputations. The patients with digit amputations had 7.2 wk of therapy and lost 6.8 wk of work. Ninety percent of the amputees rated their function as good or excellent, in contrast to 44.4% of the replantation patients. These findings are supported by existing literature that suggests that single-digit replants do not help with function of the whole hand, which is the therapeutic aim.

Ethanol-derived immunoreactive species formed by free radical mechanisms

Recent studies have shown that the alpha-hydroxyethyl radical (CH3CHOH), a metabolite of ethanol, is produced in vitro and in vivo. We report studies that establish the immunogenicity of alpha-hydroxyethyl radical-derived protein adducts. Rat liver microsomes incubated in the presence of [14C]ethanol and NADPH (under aerobic conditions) incorporate 14C into acid-stable adducts. Incorporation was markedly inhibited by the free-radical scavenger alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone. Rabbits immunized with rat liver microsomes that had been preincubated with ethanol and NADPH generated antibodies that recognized polylysine-acetaldehyde adducts and adducts formed by incubation of proteins with an alpha-hydroxyethyl radical-generating system (ethanol plus H2O2 plus Fe2+). Rabbits immunized with microsomes that had been preincubated with ethanol and NADPH plus alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone generated antibodies that recognized polylysine-acetaldehyde adducts. However, their reactivity against alpha-hydroxyethyl-derived protein epitopes was greatly reduced or was virtually abolished. Data indicate that microsomes metabolizing ethanol generate two types of adducts, acetaldehyde-derived adducts and alpha-hydroxyethyl radical-derived adducts, both of which are immunogenic. Immunization of rabbits with alpha-hydroxyethyl-bovine serum albumin adducts led to the production of antibodies that recognized alpha-hydroxyethyl-rabbit serum albumin adducts but did not recognize the native protein. Chronic alcohol feeding of rats led to the production of antibodies that recognized alpha-hydroxyethyl-rat serum albumin adducts but did not recognize rat serum albumin. The study (i) indicates that alpha-hydroxyethyl radical-derived protein adducts are immunogenic, (ii) supports earlier work that proposed that alpha-hydroxyethyl radicals generated in different systems bind covalently to proteins, and (iii) demonstrates the formation of antibodies to alpha-hydroxyethyl-derived protein adducts after chronic alcohol ingestion in vivo. The findings may have implications in the identification of chronic alcohol abuse and the pathogenesis of alcohol-induced organ damage.

International comparative study of cefepime and ceftazidime in the treatment of serious bacterial infections

In this randomized multicentre study, we compared the safety and efficacy of cefepime, 2.0 g bd i.v., with that of ceftazidime, 2.0 g tid i.v., as initial treatment of adult patients with serious infections of bacterial aetiology. Three hundred and forty-eight patients were entered into the study, 173 received cefepime and 175 ceftazidime. The treatment groups were comparable with respect to demographic characteristics, including the types of infection (cefepime/ceftazidime: urinary tract, 55/72; lower respiratory tract, 83/74; skin and soft tissue, 23/14; septicaemia, 81/81; and others, 15/5). Gram-positive bacteria were identified as pathogens on 86 occasions (cefepime/ceftazidime: 48/41), including 20 Staphylococcus aureus isolates (13/7) and 27 Streptococcus pneumoniae isolates (14/13). Gram-negative bacilli were isolated on 261 occasions (126/135), and included 219 Enterobacteriaceae (cefepime/ceftazidime: 108/111) and 34 strains of Pseudomonas aeruginosa (14/20). An intention-to-treat analysis revealed satisfactory clinical response rates of 80% and 79% for the cefepime and ceftazidime groups, respectively, and bacteriological eradication rates of 85% and 88% for the cefepime and ceftazidime groups, respectively. Of patients with microbiologically documented infections, 86% (84 of 98) treated with cefepime and 87% (94 of 108) treated with ceftazidime responded satisfactorily. Thirty-two patients (19%) treated with cefepime and 26 (15%) treated with ceftazidime died. Thirty-six patients in the cefepime group and 23 in the ceftazidime group experienced adverse events; therapy was discontinued prematurely in four and two patients in the cefepime and ceftazidime groups, respectively. Of the patients experiencing adverse events, 22 (13%) treated with cefepime developed intolerance at the injection site, compared with 11 (6%) treated with ceftazidime (P = 0.045). In conclusion, twice-daily cefepime (2 g bd) is at least as effective as ceftazidime (2 g tid), as initial empirical therapy for serious bacterial infections in non-neutropenic patients.

Fibromatosis on the dorsum of the nose

An extremely rare case of fibromatosis in a 25-year-old Indian male is reported. The clinical examination and pre-operative findings were suggestive of a benign neoplasm, probably of neurogenic origin. The mass was well circumscribed and could be shelled out en masse. Histopathological examination showed it to be fibromatosis. An external rhinoplasty approach enabled a complete wide excision to be performed without any resulting cosmetic defect.

Respiratory responses and blood sugar level of the crab, Barytelphusa cunicularis (Westwood), exposed to mercury, copper and zinc

Barytelphusa cunicularis (Westwood), a freshwater crab was exposed to mercuric chloride, copper sulphate and zinc sulphate from 0 to 12 hr and the oxygen consumption of the animal was measured in order to study the stress caused by these heavy metals. Normal oxygen consumption was affected by the three heavy metals. Similarly, crabs exposed to sublethal concentrations of the same pollutants for 24, 48, 72 and 96 hr showed an elevation in the blood sugar level with a maximum increase at 48 hr. The results indicate a switch towards glycolysis in order to overcome the anaerobic stress caused by the heavy metals.

Inhaled steroids in patients with bronchiectasis

The effect of inhaled beclomethasone diproprionate (1500 micrograms day-1) on symptoms, pulmonary function and sputum production was examined in a double-blind, placebo-controlled, cross-over study in 20 patients with bronchiectasis. An 18% reduction in daily sputum production (P less than 0.003) was observed on treatment with inhaled steroid compared to placebo. A small, significant, improvement in morning peak expiratory flow rate (P less than 0.03) and forced expiratory volume in 1 s (P less than 0.03) was seen but the absolute changes are unlikely to be of clinical importance. Symptom scores for cough improved significantly (P less than 0.02). Inhaled steroids may have a role in the management of bronchiectasis by reducing cough and sputum production.

Utilization of circulating glutathione by nodular and cancerous intact rat liver

The relationship of the rate of extraction of circulating glutathione (GSH) to the level of activity of gamma-glutamyltransferase (GGT) of hepatocytes of nodular and of cancer-bearing livers was studied in rats perfused in situ via the portal vein. Fischer adult male rats with many nodules (10 rats) or few (nine rats) liver nodules and four rats with hepatomas were compared as to their ability to remove GSH (10 microM) from the perfusate. The rate of extraction of infused GSH was directly proportional to the numbers of GGT(+)-hepatocytes in the liver tissue, inhibitable completely by adding the GGT inhibitor serine borate at 6-8 mM in the perfusate, and significantly enhanced in all rats by adding the gamma-glutamyl acceptor glycyl-glycine to the perfusate. These results suggest that nodules and cancers are able to remove GSH much more efficiently from the circulation than the surrounding liver tissue and that their enhanced GSH utilization is directly dependent on their GGT activity, which is present at much higher levels than in the surrounding tissues. The increases in GGT activity in nodule hepatocytes and enhanced ability to utilize GSH could be critical factors in the response to resistance selection of chemical hepatocarcinogenesis.

Nonarticular complication of heterotopic ossification: a clinical review

Heterotopic ossification (HO) is a complication in neurologic lesions such as head injury and spinal cord injury. Limitation of range of motion and ankylosis as results of HO are well documented. In this report, ten instances of nonarticular complications after development of HO are described. There were three instances of vascular compression, five instances of ulnar nerve compression at the elbow, and two instances of suspected lymphedema. Clinical findings and radiographic evidence of these complications are described. Clinicians should be aware of these complications when HO is diagnosed. In addition, HO should be considered in the differential diagnosis of deep venous thrombosis in spinal cord injured and head injured patients.

Role of hepatic gamma-glutamyltransferase in the degradation of circulating glutathione: studies in the intact guinea pig perfused liver

The role of hepatic gamma-glutamyltransferase in the breakdown of circulating glutathione was studied in the perfused guinea pig liver. Hepatic gamma-glutamyltransferase activity in the guinea pig is sevenfold higher than in the rat and is comparable to its activity in man. Guinea pig livers were found to remove, in a single pass, 50% to 90% of glutathione (10 to 50 mumol/L) added to the portal perfusate. Removal of portal glutathione was totally dependent on the activity of gamma-glutamyltransferase and led to the near quantitative appearance of cysteinyl-glycine and cysteine in the caval perfusate. Glutathione removal by the intact liver followed saturation with a Michaelis constant (Km) of 59 mumol/L for glutathione and a maximum velocity of 235 nmol glutathione/min/gm of liver weight. The capacity of the guinea pig liver to remove circulating glutathione was estimated to be sevenfold to 10-fold higher than its net rate of output of glutathione into the circulation. Inhibition of gamma-glutamyltransferase activity in the perfused liver led to threefold to sixfold increases in the hepatic output of glutathione into the circulation, indicating that more than two thirds of glutathione transported extracellularly is broken down. Data obtained demonstrate a major role of hepatic gamma-glutamyltransferase, both in the removal of portally carried glutathione and in the degradation of glutathione molecules released by the liver itself into the sinusoids. These findings suggest the existence of an intraorgan transport of glutathione in the liver, whereby periportal cells could provide glutathione precursors to pericentral cells.

Effect of ethanol on splanchnic hemodynamics in awake and unrestrained rats with portal hypertension

Alcoholic liver disease is frequently accompanied by portal hypertension. We have previously shown that alcohol intake in awake, unrestrained rats is followed by an increase in portal tributary blood flow. In this study, the effect of ethanol on splanchnic hemodynamics in rats with portal hypertension was analyzed. Portal hypertension was induced by partial ligation of the portal vein. This procedure resulted in an increase in portal tributary and hepatic arterial blood flows compared to sham-operated animals. Ethanol (2 gm per kg, oral) increased portal tributary blood flow in both sham-operated and portal vein-ligated rats (sham + water = 37.6 +/- 1.4; sham + ethanol = 63.1 +/- 1.9; p less than 0.01; partial portal vein stenosis + water = 53.2 +/- 3.3; partial portal vein stenosis + ethanol = 69.5 +/- 2.2 ml.kg-1.min-1; p less than 0.01). In sham-operated rats, hepatic artery blood flow was unchanged following ethanol (sham + water = 6.6 +/- 0.7; sham + ethanol = 7.1 +/- 1.0 ml.kg-1.min-1), whereas in portal vein-ligated rats, flow was increased (partial portal vein stenosis + water = 13.7 +/- 1.4; partial portal vein stenosis + ethanol = 19.8 +/- 1.1 ml.kg-1.min-1; p less than 0.025). The adenosine receptor blocker 8-phenyltheophylline suppressed only the ethanol-induced increase in both portal tributary and hepatic artery blood flows in portal vein-ligated rats. The increases in hepatic artery and portal tributary blood flows observed in portal vein-ligated rats without ethanol were not influenced by 8-phenyltheophylline.(ABSTRACT TRUNCATED AT 250 WORDS)

Pitfalls in the design of distributed routing algorithms

The bridge algorithm adopted by the IEEE 802.1 committee for interconnecting 802 LANs requires the topology of the Extended LAN to be a Spanning Tree. A distributed algorithm to compute a spanning tree dynamically has already been published [1], and adopted by the IEEE 802.1 committee [2]. In this paper, however, we describe an alternative distributed algorithm to compute a spanning tree. This algorithm, variants of which have been implemented, initially appears simpler than the IEEE 802.1 algorithm; we show, however, that it has subtle failure modes that makes it unattractive in practice.

We also show that some failure modes of the Spanning Tree Algorithm introduced in this paper are characteristic of a broader class of distributed graph algorithms. Such algorithms potentially examine all possible path combinations between a source and destination in a graph. Thus, they suffer from exponential message overhead in topologies that have an exponential number of paths between source and destination. Attempts to fix this problem lead to extra complexity (in terms of CPU, bandwidth, memory) when compared to other algorithms. We briefly describe a second example belonging to this class, and propose that designers avoid such algorithms if restricting the topology or scale of the network is unacceptable.

Fatal infection with Mycobacterium fortuitum associated with oesophageal achalasia

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Pulmonary involvement in ulcerative colitis

Pulmonary involvement in ulcerative colitis usually presents as a rapidly progressive cough with copious amounts of sputum. Although it is rare, distressing symptoms may be relieved by inhaled steroids in 50-60% of cases. Three case reports are presented along with a review of the features of 28 other cases.

Metastatic renal cell carcinoma mimicking pleural mesothelioma

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Transparent interconnection of incompatible local area networks using bridges

No single LAN technology is sufficient to interconnect all the computers in a given plant, campus, or site. Thus it is desirable to combine different types of LANs, using a device called a Bridge, to produce an Extended LAN. Some LANs in the Extended LAN may have incompatible Data Link formats. Thus a bridge may need to encapsulate a frame originating on LAN A inside the Data Link header of another (incompatible) LAN B in order to allow the type A frame to travel over LAN B. In general, frames sent between any pair of LANs in the Extended LAN must be encapsulated across every incompatible LAN in the path between the LANs.

Bridges learn their routing information from information contained in frames they forward. Besides the problems of distinguishing various kinds of encapsulated and unencapsulated frames, the encapsulating protocol used by bridges must also solve the learning problem. This leads to a new set of considerations and solutions. We begin with a rough solution, and refine it using informal arguments and examples to lead to the final description. The stages in the description roughly mimic the design process.