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PubMed2004

Acute management of pituitary apoplexy--surgery or conservative management?

BACKGROUND AND OBJECTIVE: The rarity of pituitary apoplexy renders it a difficult subject for audit; hence there are no evidence-based standards of optimum care for such patients. The key controversy in management relates to the role of acute neurosurgical intervention. In recent years we have adopted a relatively conservative approach towards patients presenting with pituitary apoplexy. Against this background, we aimed to determine whether our less-interventional approach affected long-term clinical outcome in these patients. PATIENTS AND DESIGN: A retrospective analysis was performed to evaluate clinical presentation, management and clinical outcomes in a cohort of patients who presented acutely with pituitary apoplexy during the period 1994-2004. Data from 33 patients (13 female) were included, with a mean age of 52 (range 27-79) years and mean follow-up duration of 3.7 (0.4-10.1) years. RESULTS: The most common presenting symptoms were headache (97%), visual deficits (82%) and nausea/vomiting (78%). Fifteen patients (46%) underwent transsphenoidal surgery while 18 were managed conservatively. Indications for surgery were deteriorating visual deficit (n = 13), hemiparesis (n = 1) and altered conscious level (n = 1). Eight patients in the surgical group had ocular paresis that resolved in 63% following surgery, and seven had visual field defects with recovery in 57% postsurgery. Conservative management was reserved for patients with absent, or evidence of resolving, visual deficits at presentation. In this group, seven presented initially with ocular paresis and six with visual field defects but all made full recoveries. Of the patients managed neurosurgically, 87% required long-term glucocorticoid replacement and 60% required long-term thyroid hormone replacement. Conservatively managed patients required glucocorticoid replacement in 72% and thyroid hormone replacement in 72% of cases (P = NS between the two groups). Sex steroid replacement was required in 67% and 83% of patients managed neurosurgically and conservatively respectively (P = NS). At latest follow-up one patient in the conservatively managed group had required surgery and one in the surgically managed group had received pituitary radiotherapy, in both instances due to evidence of tumour regrowth on magnetic resonance imaging (MRI). CONCLUSION: Our findings suggest that patients presenting with pituitary apoplexy in whom visual deficits are stable or improving may be managed expectantly as there is no identifiable deleterious effect on visual or endocrine outcome. One patient from each group experienced tumour regrowth that necessitated further treatment intervention, highlighting the importance of long-term follow-up in patients with pituitary apoplexy.

Acute Disease↗
PubMed1993

Conservation and evolution of the rpsU-dnaG-rpoD macromolecular synthesis operon in bacteria.

The macromolecular synthesis (MMS) operon contains three essential genes (rpsU, dnaG, rpoD) whose products (S21, primase, sigma-70) are necessary for the initiation of protein, DNA, and RNA synthesis respectively. PCR amplifications with primers complementary to conserved regions within these three genes, and subsequent DNA sequencing of rpsU-dnaG PCR products, demonstrate that the three genes appear to be contiguous in 11 different Gram-negative species. Within the Gram-negative enteric bacterial lineage, the S21 amino acid sequence is absolutely conserved in 10 species examined. The putative nuteq antiterminator sequence in rpsU consists of two motifs, boxA and boxB, conserved in primary sequence and secondary structure. The terminator sequence, T1, located between rpsU and dnaG is conserved at 31 positions in nine enterobacterial species, suggesting the importance of primary sequence in addition to secondary structure for transcription termination. The intergenic region between rpsU and dnaG varies in size owing to the presence or absence of the Enterobacterial Repetitive Intergenic Consensus (ERIC) DNA element. The rpoD gene contains rearrangements involving a divergent sequence, although two carboxy-terminal regions which encode functional domains are conserved in primary sequence and spacing. Our data suggest that primary sequence divergence and DNA rearrangements in both coding and non-coding sequences account for the interspecies variation in operon structure. However, MMS operon gene organization and cis-acting regulatory sequences appear to be conserved in diverse bacteria.

Bacteria↗
PubMed1997

Quality of life after breast conservation or mastectomy: a systematic review.

BACKGROUND: For early breast cancer, survival after breast conservation is similar to that after mastectomy. Some women may not have a clear preference and wish to have further information about quality of life experienced after the alternative treatments. This paper describes a systematic review of randomized trials on mastectomy versus breast conservation for which there are data on quality of life or psychosocial outcomes. METHODS: Literature was reviewed to find all randomized controlled trials comparing breast conservation to mastectomy, with quality of life or psychological effects as an outcome. Studies were then critically appraised by two reviewers independently and any disagreements about their quality and results resolved by discussion. RESULTS: A total of six randomized trials met our inclusion criteria. In general, they are of poor quality. Women who had breast conservation had a more favourable body image of themselves than those who had mastectomy in all five studies in which it was examined. The evidence was statistically inconclusive for all the other dimensions measured, namely perceptions of psychological health, sexual health, physical health, fear of the future and global quality of life. Radiotherapy may be a determinant of poorer psychological health and body image. CONCLUSIONS: Apart from body image, it is unclear whether breast conservation or mastectomy results in better psychosocial outcomes. Moreover, the studies were done before evidence was available to inform women about the equivalence of survival with these alternative treatments. Therefore there is inadequate information available to help many women decide about their choice of treatment in the future. Preference trials should be conducted, using standardized quality-of-life measures, in which women who are uncertain about which treatment to choose are randomized to breast conservation or mastectomy.

Breast Neoplasms↗
PubMed2005

Duck (Anas platyrhynchos), Japanese quail (Coturnix coturnix japonica) and other avian interleukin-2 reveals significant conservation of gene organization, promoter elements and functional residues.

We compared the gene, promoter and cDNA sequences, and the predicted protein structure of duck and quail interleukin-2 (IL-2), a major immunomodulatory cytokine, with the known sequences of other avian and human IL-2. Analysis of the gene organization showed significant similarity with the overall organization of mammalian IL-2 genes, with four exons and three introns and a very short 5' untranslated regions. The second intron was the biggest in all the IL-2 sequences. The third intron was of similar size in chicken and quail, whereas in duck it was found to be slightly longer. Promoter sequence analysis of the IL-2 gene revealed remarkable conservation of the functionally important residues. The transcription factor binding sites such as those for AP-1, NF-AT, CD 28 RE and OCT, the TATA box and the predicted transcription start site with respect to chicken IL-2 sequence showed total conservation in duck, quail and turkey IL-2 promoters. Comparative analysis of the avian IL-2 cDNAs such as those of chicken, turkey, duck, quail, goose and Muscovy duck, revealed significant conservation of the nucleotide and predicted amino acid sequences. They showed nucleotide identity levels varying from 75% to 85%, amino acid level identity from 58% to 72% and amino acid similarity from 71% to 80% with each other. In the predicted protein secondary structure, the four essential alpha-helices and the hydrophobic amino acids in the heptad repeats forming the core structure of IL-2 molecules were conserved in all the avian and the human IL-2. The present study reveals high-level conservation of the gene; cDNA structure and regulatory elements of avian IL-2. This indicates highly conserved functions and probable functional cross-reactivity of this major immunomodulatory cytokine among birds.

Animals↗
PubMed1994

Meningococcal group A lipooligosaccharides (LOS): preliminary structural studies and characterization of serotype-associated and conserved LOS epitopes.

Structural studies indicate that the neisserial lipooligosaccharides (LOS) are composed of an oligosaccharide (OS) portion with a phosphorylated diheptose (Hep) core attached to the toxic lipid A moiety. A conserved meningococcal LOS epitope, defined by monoclonal antibody (MAb) D6A, is expressed on group A and many group B and C meningococci of different LOS serotypes (J. J. Kim, R. E. Mandrell, H. Zhen, M. A. Apicella, J. T. Poolman, and J. M. Griffiss, Infect. Immun. 56:2631-2638, 1988). This MAb-defined D6A epitope is immunogenic in humans (M. M. Estabrook, R. E. Mandrell, M. A. Apicella, and J. M. Griffiss, Infect. Immun. 58:2204-2213, 1990; M. M. Estabrook, C. J. Baker, and J. M. Griffiss, J. Infect. Dis. 197:966-970, 1993). In this study, we characterize this important MAb-defined LOS epitope. Serotype L10 and L11 group A meningococal LOS were chemically modified and used to investigate what portion of the LOS molecule is important for expression of the conserved (D6A) epitope and serotype-associated LOS epitopes by use of immunoblotting techniques and selected MAbs as probes. Preliminary structural characterization of the LOS was also accomplished by electrospray ionization-mass spectrometry. Our results indicate the following. (i) Antibodies that recognize the serotype-associated or conserved LOS epitopes recognize the OS portion of the LOS. (ii) The phosphorylated diheptose core region of the OS is essential for expression of the conserved D6A epitope. (iii) The lipid portion of the molecule is important for optimum expression of the LOS epitopes. (iv) The proposed compositions of the O-deacylated LOS are consistent with the presence of a phosphorylated diheptose core and are as follows: for O-deacylated L10 LOS, 3Hex (hexose), 1HexNAc (N-acetylhexosamine), 2KDO (2-keto-3-deoxy-D-manno-octulosonic acid), 2Hep (heptose), 1PEA or 2PEA (phosphoethanolamine), and O-deacylated lipid A; and for O-deacylated L11 LOS, 2Hex, 1HexNAc, 2KDO, 2Hep, 2PEA, and O-deacylated lipid A. Because the phosphorylated diheptose core region of the LOS is essential for the formation of a conserved LOS epitope (D6A) that is immunogenic in humans, care should be taken to maintain stereochemical requirements for the expression of this conserved epitope in the design of effective, nontoxic LOS vaccines.

Animals↗
PubMed1996

Dominance of conserved B-cell epitopes of the Plasmodium falciparum merozoite surface protein, MSP1, in blood-stage infections of naive Aotus monkeys.

We have shown that conserved B epitopes were immunodominant in animals hyperimmunized with parasite-purified or recombinant merozoite surface protein MSP1 of Plasmodium falciparum. Cross-priming studies also suggested that a conserved T-helper epitope(s) is efficient in inducing the anti-MSP1 antibody response. In this study, we determined whether a similar profile of immune responses was induced during live P. falciparum infections. Naive Aotus monkeys were infected by blood-stage challenge with either one of the two dimorphic MSP1 alleles represented by the FUP and FVO parasites. Sera collected after parasite clearance were analyzed by enzyme-linked immunosorbent assays (ELISAs). Monkeys infected with parasites carrying one allelic form of MSP1 had antibodies that were equally reactive with homologous or heterologous MSP1s. This preferential recognition of conserved epitopes of MSP1 was confirmed by competitive binding ELISAs. Studies with Plasmodium yoelii and P. falciparum show that the C-terminal 19-kDa fragment of MSP1, MSP1(19), is the target of protective immunity. Thus, monkey sera were assayed for recognition with recombinant MSP1(19)s expressing variant and conserved B epitopes. Results of direct and competitive binding ELISAs showed that the anti-MSP1(19) antibodies were also directed primarily against conserved determinants. The similarities between vaccine- or infection-induced antibody responses suggest a possible reciprocal enhancement of the two populations of anti-MSP1 antibodies when a subunit MSP1 vaccine is introduced into populations living in areas where malaria is endemic. This together with previous observations that conserved determinants are important in MSP1-mediated immunity provides an optimistic outlook that a subunit MSP1 vaccine may be effective and practical for field applications in malaria-exposed populations.

Alleles↗
PubMed1996

Antibodies to a conserved-motif peptide sequence of the Plasmodium falciparum thrombospondin-related anonymous protein and circumsporozoite protein recognize a 78-kilodalton protein in the asexual blood stages of the parasite and inhibit merozoite invasion in vitro.

Athrombospondin-related anonymous protein (TRAP) of the human malaria parasite Plasmodium falciparum shares highly conserved amino acid sequence motifs with the circumsporozoite protein of all plasmodia sequenced so far, as well as with unrelated proteins like thrombospondin and properdin. Although it was first described as an asexual blood stages protein, there has been some controversy about its expression in these stages. Pursuant to our interest in the conserved sequences within the malaria antigens, we synthesized an 18-residue peptide (18-mer) representing a conserved motif of TRAP and raised polyclonal antibodies against it. In an immunoblot assay in which we probed proteins from the asexual blood stages of the parasite, we found that this antibody recognized predominantly a 78-kDa protein in the whole parasite lysate. Furthermore, in another immunoblot, the recombinant TRAP constructs containing the conserved-motif sequence were distinctly recognized by the antipeptide antibodies, whereas a construct lacking the motif sequence was not, suggesting that the antibodies specifically cross-reacted with a protein which might be a TRAP-like protein present in the asexual blood stages of the parasite. Also, in an immunofluorescence assay, this antibody brightly stained the acetone-fixed trophozoites of the parasite. Most significantly, anti-18-mer immunoglobulin G, as well as antipeptide antibody against a smaller (nonamer) construct representing the most conserved motif within the 18-mer, inhibited the merozoite invasion of erythrocytes in a dose-dependent manner. These results provide evidence of the expression of TRAP or a TRAP-like protein in the asexual blood stages of the parasite and of a possible role of the conserved motifs in the parasite-host cell interaction during the process of invasion.

Amino Acid Sequence↗
PubMed2004

Properties of Bacillus subtilis sigma A factors with region 1.1 and the conserved Arg-103 at the N terminus of region 1.2 deleted.

sigma factors in the sigma(70) family can be classified into the primary and alternative sigma factors according to their physiological functions and amino acid sequence similarities. The primary sigma factors are composed of four conserved regions, with the conserved region 1 being divided into two subregions. Region 1.1, which is absent from the alternative sigma factor, is poor in conservation; however, region 1.2 is well conserved. We investigated the importance of these two subregions to the function of Bacillus subtilis sigma(A), which belongs to a subgroup of the primary sigma factor lacking a 254-amino-acid spacer between regions 1 and 2. We found that deletion of not more than 100 amino acid residues from the N terminus of sigma(A), which removed part or all region 1.1, did not affect the overall transcription activity of the truncated sigma(A)-RNA polymerase in vitro, indicating that region 1.1 is not required for the functioning of sigma(A) in RNA polymerase holoenzyme. This finding is consistent with the complementation data obtained in vivo. However, region 1.1 is able to negatively modulate the promoter DNA-binding activity of the sigma(A)-RNA polymerase. Further deletion of the conserved Arg-103 at the N terminus of region 1.2 increased the content of stable secondary structures of the truncated sigma(A) and greatly reduced the transcription activity of the truncated sigma(A)-RNA polymerase by lowering the efficiency of transcription initiation after core binding of sigma(A). More importantly, the conserved Arg-103 was also demonstrated to be critical for the functioning of the full-length sigma(A) in RNA polymerase.

Amino Acid Sequence↗
PubMed2007

Conservative treatment for patent ductus arteriosus in the preterm.

BACKGROUND: A patent ductus arteriosus (PDA) is common among preterms, and prophylactic medical treatment has been advocated as the first-line approach. Conservative treatment may result in similar outcome, but without exposure to the harmful side effects of medication. A retrospective analysis revealed a ductal closure rate of 94% after conservative treatment with adjustment of ventilation (lowering the inspiratory time and increasing positive end expiratory pressure) and fluid restriction. OBJECTIVE: To study prospectively over one year the rate of PDA closure, and morbidity and mortality following conservative treatment. METHOD: Prospective study (1 January 2005 - 31 December 2005) including 30 newborns <or=30 weeks' gestation, all of whom were being ventilated and required surfactant. Echocardiography was performed 48-72 h after birth. Clinically important PDA was conservatively treated as described above. The percentage of children with PDA, ductal ligation and major complications was determined. RESULTS: Ten neonates (33%) developed a clinical important PDA. Following conservative treatment the duct closed in all neonates (100%), and none required ductal ligation or medical treatment. The rates of major complications were no higher than those reported by the Vermont Oxford Network and in the literature. CONCLUSION: The managed care plan resulted in an overall ductal closure rate of 100%. These results suggest that conservative treatment of PDA is a worthy alternative to prophylactic medical treatment.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2002

Suturing versus conservative management of lacerations of the hand: randomised controlled trial.

OBJECTIVE: To assess the difference in clinical outcome between lacerations of the hand closed with sutures and those treated conservatively. DESIGN: Randomised controlled trial. SETTING: Emergency department in a tertiary hospital. PARTICIPANTS: Consecutive patients presenting between 16 February and 30 November 2000 with uncomplicated lacerations of the hand (full thickness <2 cm; without tendon, joint, fracture, or nerve complications) who would normally require sutures. 154 patients were eligible, 58 refused, and 5 were missed; 91 patients with 95 lacerations were enrolled. INTERVENTION: Participants were randomised to suturing or conservative treatment. MAIN OUTCOME MEASURES: Primary outcome was cosmetic appearance after three months, rated on a previously validated visual analogue scale. Duration of treatment, pain during treatment, patients' assessment of their outcome, and the time for patients to resume normal activities were also measured. RESULTS: Participants treated with sutures and those treated conservatively did not differ significantly in the assessment of cosmetic appearance by independent blinded doctors after three months: 83 mm v 80 mm, (mean difference 3 (95% confidence interval -1 to 8) mm) on the visual analogue scale. The mean time to resume normal activities was the same in both groups (3.4 days). Patients treated conservatively had less pain (difference 18 (12 to 24) mm) and treatment time was 14 (10 to 18) min shorter. CONCLUSION: Similar cosmetic and functional outcomes result from either conservative treatment or suturing of small uncomplicated lacerations of the hand, but conservative treatment is faster and less painful.

Esthetics↗
PubMed1998

Is resolution of vesicoureteric reflux by conservative management predictable in patients with myelodysplasia?

OBJECTIVE: To evaluate the probable factors that might predict the outcome of conservative management of vesicoureteric reflux (VUR) in myelodysplastic patients. PATIENTS AND METHODS: A retrospective review of 24 children with VUR secondary to neurogenic bladder (15 girls and 9 boys, age range 1-18 years) out of 75 myelodysplasia patients between 1994 and 1996 was made. Patients were grouped according to their response to conservative management: Group I: patients with their VUR resolved or downgraded (n = 15), and group II: patients with their VUR unchanged or increased (n = 9). The following parameters were compared between the two groups: age, sex, VUR grade and laterality, urodynamic parameters (bladder capacity, compliance, leak point pressure), type of bladder neuropathy, accompanying neuropathology (walking problem, anal incontinence). RESULTS: Most of the parameters studied failed to predict the outcome of conservative management of VUR in patients with neurogenic bladder dysfunction. Higher grades of VUR if bilateral seem to benefit more from conservative management than lower grades do. Conservative management appears to be more effective in hyperreflexic bladders than areflexic bladders in terms of VUR resolution. CONCLUSION: Although prediction of patients resistant to conservative management of VUR could save myelodysplastic children from prolonged risk of renal damage, current methods of evaluation are of very little help in this aspect.

Adolescent↗
PubMed1976

Impaired renal conservation of sodium and chloride during sustained correction of systemic acidosis in patients with type 1, classic renal tubular acidosis.

In 10 patients with classic renal tubular acidosis in whom correction of acidosis was sustained with orally administered potassium bicarbonate, renal conservation of sodium was evaluated when dietary intake of sodium was restricted to 9--13 meq/day. In five patients, renal conservation of sodium was impaired by at least one criterion of impairment. In the remaining patients, renal conservation of sodium appeared to be relatively well-maintained, but an impairment could not be excluded. In each of six patients studied during induced water diuresis, including two in whom renal conservation of sodium was not unequivocally impaired, the minimal urinary concentrations of sodium were inappropriately high and the urinary excretion rates of sodium were flow-dependent. These results provide direct evidence that an abnormality in renal transport of sodium can occur in classic renal tubular acidosis, and compel a reconsideration of the pathophysiology of disordered renal transport of sodium in this disorder. The results indicate that in at least some patients with classic renal tubular acidosis impaired renal conservation of sodium is not exclusively a reversible consequence of the renal acidification defect. These findings raise the question whether renal transport of sodium is unimpaired in any patients with classic renal tubular acidosis. In the presently studied patients, the impairment in renal conservation of sodium appeared to be in part the consequence of an impaired ability of the vasopressin-responsive segments of the distal nephron to generate and maintain appropriately steep transepithelial sodium concentration gradients.

Acid-Base Equilibrium↗
PubMedDate not supplied

Neck dissection: radical or conservative.

Four hundred and forty-five neck dissections for epidermoid carcinoma over a 10-year period are reviewed as to local recurrence of neck disease. Three hundred and forty-seven dissections were radical en bloc procedures and in 98 a modified conservative technique was utilized. Cervical lymph node classification was applied and a comparison made of the two techniques. A review of the anatomy of cervical fascias and the technique of conservative neck dissection is given. Evaluation of this series of cases indicate that the control of local disease in the neck in the N0 and N1 groups is is accomplished as well with conservative dissection as with radical neck dissection. The number of conservative neck dissections for N2 disease was too limited for accurate comparison. There were no conservative neck dissections done for N3 disease. We suggest that conservative neck dissection be utilized for subclinical and N1 disease and that the classic en bloc dissection be reserved for N2 and N3 situations.

Carcinoma, Squamous Cell↗
PubMed2005

Conservation of pregnancy-specific glycoprotein (PSG) N domains following independent expansions of the gene families in rodents and primates.

BACKGROUND: Rodent and primate pregnancy-specific glycoprotein (PSG) gene families have expanded independently from a common ancestor and are expressed virtually exclusively in placental trophoblasts. However, within each species, it is unknown whether multiple paralogs have been selected for diversification of function, or for increased dosage of monofunctional PSG. We analysed the evolution of the mouse PSG sequences, and compared them to rat, human and baboon PSGs to attempt to understand the evolution of this complex gene family. RESULTS: Phylogenetic tree analyses indicate that the primate N domains and the rodent N1 domains exhibit a higher degree of conservation than that observed in a comparison of the mouse N1 and N2 domains, or mouse N1 and N3 domains. Compared to human and baboon PSG N domain exons, mouse and rat PSG N domain exons have undergone less sequence homogenisation. The high non-synonymous substitution rates observed in the CFG face of the mouse N1 domain, within a context of overall conservation, suggests divergence of function of mouse PSGs. The rat PSG family appears to have undergone less expansion than the mouse, exhibits lower divergence rates and increased sequence homogenisation in the CFG face of the N1 domain. In contrast to most primate PSG N domains, rodent PSG N1 domains do not contain an RGD tri-peptide motif, but do contain RGD-like sequences, which are not conserved in rodent N2 and N3 domains. CONCLUSION: Relative conservation of primate N domains and rodent N1 domains suggests that, despite independent gene family expansions and structural diversification, mouse and human PSGs retain conserved functions. Human PSG gene family expansion and homogenisation suggests that evolution occurred in a concerted manner that maintains similar functions of PSGs, whilst increasing gene dosage of the family as a whole. In the mouse, gene family expansion, coupled with local diversification of the CFG face, suggests selection both for increased gene dosage and diversification of function. Partial conservation of RGD and RGD-like tri-peptides in primate and rodent N and N1 domains, respectively, supports a role for these motifs in PSG function.

Amino Acid Motifs↗
PubMed2004

Conservative management of asymptomatic spinal lipomas of the conus.

OBJECTIVE: The natural history of spinal lipomas of the conus (SLCs) has not been well studied. Because of disappointing long-term results with early surgical treatment of asymptomatic children with SLCs, we have followed a protocol of conservative management for these patients. The results are presented in this report. METHODS: Since 1994, all asymptomatic children with SLCs who were examined at Necker-Enfants Malades Hospital were subject to a protocol of conservative management. The records for those patients were reviewed, to determine the incidence and timing of neurological deterioration. The findings were compared with those for a previously reported historical cohort of asymptomatic patients who underwent early surgery at our institution. RESULTS: Fifty-three asymptomatic children (35 girls and 18 boys) with SLCs were monitored, with conservative management. During a mean follow-up period of 4.4 years (range, 12 mo to 9 yr), 13 patients (25%) exhibited neurological deterioration. At 9 years, the actuarial risks of deterioration, as determined with the Kaplan-Meier method, were 33% for the conservatively treated patients and 46% for the surgically treated patients. With a Cox proportional-hazards model, there was no significant difference in the risks of neurological deterioration for patients who were treated conservatively and those who underwent early surgery. CONCLUSION: The incidences and patterns of neurological deterioration seemed to be very similar, regardless of whether early surgery was performed. These results suggest that conservative treatment of asymptomatic patients is a reasonable option. A more definitive randomized study will be required to clarify the relative efficacy of early surgery for SLCs among asymptomatic patients.

Actuarial Analysis↗
PubMed1981

The contralateral ear in acoustic tumors and hearing conservation.

Hearing conservation in acoustic tumor surgery is an admirable goal and a logical extension of micro neurotologic surgery, but ideal candidates for conservation are few, and attempts to preserve hearing in those few fail in about half of all cases. Conserved hearing most often falls far beyond a range that will provide binaural function and is, therefore, of questionable use. The problem of hearing conservation in acoustic tumor surgery is rationally approached based upon the implications of the total presurgical overview, particularly with reference to age, general health, tumor size, and especially hearing in the tumor ear, the contralateral ear, and interaural relationships. Technical considerations, the morbidity and mortality, and, finally, probability factors are reviewed from the literature, The patient's consideration regarding potentials for hearing conservation, his need for conservation, and alternative options are discussed. Rehabilitative options for unilateral hearing impairment are discussed. A review of the amplification requirements of 45 acoustic tumor patients - 5 or more years postoperative - indicated that three-quarters had normal hearing in the contralateral ear, 24% of whom required CROS amplification; 67% of the remaining quarter had mild to moderate hearing losses and were effectively wearing BiCROS aids. None were rehabilitated with monaural aids; 20% of the entire group studied had demonstrated some degree of additional hearing loss in the non-tumor ear since surgery.

Amplifiers, Electronic↗
PubMed2003

Conservative treatment as an option in the management of pancreatic pseudocyst.

BACKGROUND: Management of pancreatic pseudocysts is associated with considerable morbidity (15-25%). Traditionally, pancreatic pseudocysts have been drained because of the perceived risks of complications including infection, rupture or haemorrhage. We have adopted a more conservative approach with drainage only for uncontrolled pain or gastric outlet obstruction. This study reports our experience. PATIENTS AND METHODS: A consecutive series of 36 patients with pancreatic pseudocysts were treated over an 11-year period in one district general hospital serving a population of 310,000. This study group comprised of 19 men and 17 women with a median age of 55 years (range, 10-88 years). Twenty-two patients had a preceding attack of acute pancreatitis whilst 12 patients had clinical and radiological evidence of chronic pancreatitis. The aetiology comprised of gallstones (16), alcohol (5), trauma (2), tumour (2), hyperlipidaemia (1) and idiopathic (10). RESULTS: All patients were initially managed conservatively and intervention, either by radiological-assisted external drainage or cyst-enteric drainage (by surgery or endoscopy), was only performed for persisting symptoms or complications. Patients treated conservatively had 6 monthly follow-up abdominal ultrasound scans (USS) for 1 year. Fourteen of the 36 patients (39%) were successfully managed conservatively, whilst 22 patients required intervention either by percutaneous radiological drainage (12), by endoscopic cystogastrostomy (1) or by open surgical cyst-enteric anastomosis (9). Median size of the pancreatic pseudocysts in the 14 patients managed conservatively (7 cm) was nearly similar to that of the 22 patients requiring intervention (8 cm). The most common indications for invasive intervention in the 22 patients were persistent pain (16), gastric outlet obstruction (4), jaundice (1) and dyspepsia with weight loss (1). Although one patient required surgery for persistent pain, no other patients required urgent or scheduled surgery for complications of untreated pancreatic pseudocysts. Two of the 12 patients treated by percutaneous radiological drainage had recurrence of pancreatic pseudocysts requiring surgery. Two patients developed an intra-abdominal abscess following cyst-enteric drainage of pancreatic pseudocysts and one patient had a pulmonary embolism. On the mean follow-up of 37.3 months, one patient with alcoholic pancreatitis died 5 months after surgical cyst-enteric bypass. CONCLUSIONS: These results suggest that many patients with pancreatic pseudocysts can be managed conservatively if presenting symptoms can be controlled.

Adolescent↗
PubMed1991

Conservation and metaphor acquisition in hearing-impaired children. Some relationships with communication mode, hearing acuity, schooling, and age.

This study focused on conservation and metaphor acquisition in 35 hearing-impaired children who used different modes of communication and who spanned a wide age range. Children who used either cued speech or oral-aural communication modes were tested at two different school sites. Relationships were determined between the dependent variables, conservation and metaphor, and the independent variables of age, degree of hearing loss, years of schooling, and mode of communication. Findings revealed a significant positive relationship between conservation and metaphor in both communication modes. Significant relationships between age and metaphor and between age and conservation were also found, suggesting that experience plays an important role in understanding both of them. Neither conservation nor metaphor was significantly related to either degree of hearing loss or communication mode. The conservation order of acquisition was number (91%), weight (60%), volume (50%), and liquid (46%). Suggestions for teachers based on the findings are presented.

Adolescent↗