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Biomedical subjects

M G Wise

Publications and source records attributed to M G Wise.

At least 19 recordsLinked to original sources
PubMed2001

Methylosarcina fibrata gen. nov., sp. nov. and Methylosarcina quisquiliarum sp.nov., novel type 1 methanotrophs.

Two novel species of obligate methane-oxidizing bacteria, isolated from landfill soil, were characterized. Both strains were unusual in that some members of the population grew in irregularly shaped, refractile cell packets that resembled sarcina-like clusters. Electron microscopy revealed that the cell packets were covered with a slime layer and the cells contained many large granular inclusion bodies. The individual cells of each strain were sometimes motile and had differing morphologies. Isolate AML-C10T was always coccoidal in shape, and the cells were covered with extracellular fibrils. Isolate AML-D4T was pleomorphic, changing from rod to coccal form, sometimes exhibiting an unusual fusiform morphology. AML-D4T lacked the extensive fibrillar matrix observed with AML-C10T. Both strains utilized only methane and methanol as carbon sources. In stationary phase, the cells of each strain swelled in size and formed cysts. Aside from morphological differences, strains could also be distinguished from each other by cellular protein patterns, as well as by temperature and pH tolerances. 16S rDNA phylogenetic analysis showed that these are type I methanotrophs (family: Methylococcaceae) most closely related to the Methylobacter/Methylomicrobium clade, although they form a monophyletic grouping supported by moderately high bootstrap values. By 16S rDNA database searches, the most similar species to both isolates were Methylobacter spp. However, partial particulate methane monooxygenase sequence analysis suggested that these bacteria might be more closely related to Methylomicrobium than Methylobacter. Furthermore, cellular fatty acid profiles of the strains more closely resemble those of Methylomicrobium, although the absence of significant levels of 16:1omega5c argues for the uniqueness of these two strains. On the basis of the results described here, it is proposed that a new genus should be created, Methylosarcina gen. nov., harbouring two species, Methylosarcina fibrata sp. nov. (type species) and Methylosarcina quisquiliarum sp. nov. The type strains are AML-C10T (= ATCC 700909T = DSM 13736T) and AML-D4T (= ATCC 700908T = DSM 13737T), respectively.

Bacterial Proteins↗
PubMed1999

Factitious disorders.

Reports of factitious disorders, Munchausen's syndrome, and self-induced illness exist throughout medical history. In practice, disease simulation represents a spectrum of behaviors that range from relatively common and benign (e.g., pleading illness to avoid an unwanted social obligation) to rare and malignant forms (e.g., Munchausen's syndrome and factitious disorder by proxy). Factitious disorders are differentiated from malingering by the goal that motivates the individual's behavior. The only apparent goal in factitious illness is to gain the sick role; the goal in malingering is to gain rewards, such as compensation, or to avoid the unwanted, such as military service or jail. This article summarizes clinically relevant information on factitious disorders for primary care physicians.

Diagnosis, Differential↗
PubMed1999

Anxiety and neurological disorders.

Anxiety disorders occur quite frequently in patients who have neurologic disorders. In fact, several studies show that anxiety disorders occur more frequently than mood disorders in patients with neurologic conditions. Despite high prevalence rates, investigators have neglected the study of anxiety disorders in these patients. Two major reasons for the neglect are the diagnostic hierarchy and exclusion criterion found in Diagnostic and Statistical Manual (DSM)-III-R and DSM-IV. This article discusses problems in the diagnosis of anxiety disorders in patients with neurologic conditions and presents a brief literature review of the relationship between anxiety and neurologic disorders. In addition, the authors describe the differential diagnosis of anxiety in neurologic conditions and treatment options.

Anxiety↗
PubMed1999

Methanotroph diversity in landfill soil: isolation of novel type I and type II methanotrophs whose presence was suggested by culture-independent 16S ribosomal DNA analysis.

The diversity of the methanotrophic community in mildly acidic landfill cover soil was assessed by three methods: two culture-independent molecular approaches and a traditional culture-based approach. For the first of the molecular studies, two primer pairs specific for the 16S rRNA gene of validly published type I (including the former type X) and type II methanotrophs were identified and tested. These primers were used to amplify directly extracted soil DNA, and the products were used to construct type I and type II clone libraries. The second molecular approach, based on denaturing gradient gel electrophoresis (DGGE), provided profiles of the methanotrophic community members as distinguished by sequence differences in variable region 3 of the 16S ribosomal DNA. For the culturing studies, an extinction-dilution technique was employed to isolate slow-growing but numerically dominant strains. The key variables of the series of enrichment conditions were initial pH (4. 8 versus 6.8), air/CH(4)/CO(2) headspace ratio (50:45:5 versus 90:9:1), and concentration of the medium (1x nitrate minimal salts [NMS] versus 0.2x NMS). Screening of the isolates showed that the nutrient-rich 1x NMS selected for type I methanotrophs, while the nutrient-poor 0.2x NMS tended to enrich for type II methanotrophs. Partial sequencing of the 16S rRNA gene from selected clones and isolates revealed some of the same novel sequence types. Phylogenetic analysis of the type I clone library suggested the presence of a new phylotype related to the Methylobacter-Methylomicrobium group, and this was confirmed by isolating two members of this cluster. The type II clone library also suggested the existence of a novel group of related species distinct from the validly published Methylosinus and Methylocystis genera, and two members of this cluster were also successfully cultured. Partial sequencing of the pmoA gene, which codes for the 27-kDa polypeptide of the particulate methane monooxygenase, reaffirmed the phylogenetic placement of the four isolates. Finally, not all of the bands separated by DGGE could be accounted for by the clones and isolates. This polyphasic assessment of community structure demonstrates that much diversity among the obligate methane oxidizers has yet to be formally described.

Base Sequence↗
PubMed1997

Bacterial diversity of a Carolina bay as determined by 16S rRNA gene analysis: confirmation of novel taxa.

Carolina bays are naturally occurring shallow elliptical depressions largely fed by rain and shallow ground water. To identify members of the domain Bacteria which inhibit such an environment, we used PCR to construct a library of 16S rRNA genes (16S rDNAs) cloned from DNA extracted from the sediments of Rainbow bay, located on the Savannah River Site, near Aiken, S.C. Oligonucleotides complementary to conserved regions of 16S rDNA were used as primers for PCR, and gel-purified PCR products were cloned into vector pGEM-T. Partial sequencing of the cloned 16S rDNAs revealed an extensive amount of phylogenetic diversity within this system. Of the 35 clones sequenced, 32 were affiliated with five bacterial groups: 11 clustered with the Proteobacteria division (including members of the alpha, beta, and delta subdivisions), 8 clustered with the Acidobacterium subdivision of the Fibrobacter division (as categorized by the Ribosomal Database Project's taxonomic scheme, version 5.0), 7 clustered with the Verrucomicrobium subdivision of the Planctomyces division, 3 clustered with the gram-positive bacteria (Clostridium and relatives subdivision), and 3 clustered with the green nonsulfur bacteria. One sequence branched very deeply from the Bacteria and was found not to be associated with any of the major divisions when phylogenetic trees were constructed. Two clones did not consistently cluster with specific groups and may be chimeric sequences. None of the clones exhibited an exact match to any of the 16S rDNA sequences deposited in the databases, suggesting that most of the bacteria in Rainbow Bay are novel species. In particular, the clones related to the Acidobacterium subdivision and the Verrucomicrobium subdivision confirm the presence of novel taxa discovered previously in other molecular surveys of this type.

Bacteria↗
PubMed1997

A treatment algorithm for the management of anxiety in primary care practice.

Patients frequently present to primary care physicians with somatic symptoms that mask an underlying anxiety disorder. As a result, unnecessary diagnostic tests are ordered, and inappropriate medications are prescribed. Psychiatrists may help improve their primary care colleagues' ability to identify and treat these anxiety disorders. This paper reviews the adverse effects of untreated anxiety in managed care settings and outlines a treatment algorithm that psychiatrists may wish to use to assist primary care physicians in the cost-efficient, pharmacologic treatment of anxiety disorders in their patients.

Algorithms↗
PubMed1995

Genetic structure of a lotic population of Burkolderia (Pseudomonas) cepacia.

The genetic structure of a population of Burkholderia (Pseudomonas) cepacia isolated from a southeastern blackwater stream was investigated by using multilocus enzyme electrophoresis to examine the allelic variation in eight structural gene loci. Overall, 213 isolates were collected at transect points along the stream continuum, from both the sediments along the bank and the water column. Multilocus enzyme electrophoresis analysis revealed 164 distinct electrophoretic types, and the mean genetic diversity of the entire population was 0.574. Genetic diversity values did not vary spatially along the stream continuum. From a canonical discriminant analysis, Mahalonobis distances (measurements of genetic similarity between populations) revealed significant differences among the subpopulations at the sediment sampling points, suggesting bacterial adaptation to a heterogeneous (or patchy) microgeographical environment. Multilocus linkage disequilibrium analysis of the isolates revealed only limited association between alleles, suggesting frequent recombination, relative to binary fission, in this population. Furthermore, the dendrogram created from the data of this study and the allele mismatch distribution are typical of a population characterized by extensive genetic mixing. We suggest that B. cepacia be added to the growing list of bacteria that are not obligatorily clonal.

Alleles↗
PubMed1995

A combined treatment approach to anxiety in the medically ill.

Anxiety occurs frequently in patients who are medically ill. A proper search for the underlying cause of the anxiety is essential if the clinician is to make a correct diagnosis and initiate appropriate treatment. Two aspects of the patient's history are particularly important during assessment: the duration and severity of medical illness (and treatments) and the duration and severity of anxiety symptoms. When acute anxiety is encountered, the clinician must rule out a rapidly worsening medical condition, substance-induced anxiety (toxicity or withdrawal), and a psychological reaction to stressors associated with the medical illness. During evaluation of medically ill individuals with chronic anxiety, the clinician must rule out medical disorders that can mimic anxiety disorders, psychiatric disorders associated with anxiety symptoms, and poor adjustment to the medical illness. It is also worth remembering that anxiety disorders occur at an increased frequency in individuals who have chronic medical illness.

Aged↗
PubMed1993

Diagnostic considerations and treatment approaches to underlying anxiety in the medically ill.

Autonomic and somatic manifestations of anxiety are common in medically ill patients. When anxiety symptoms occur in such patients, the psychiatrist's ability to rapidly identify anxiety and perform a proper differential diagnosis is important, and can be life-saving. For example, a patient with deteriorating cardiac or pulmonary function may be misidentified as primarily "anxious" and referred to the psychiatrist. The change in the patient's medical status is missed until the situation becomes critical. Medication side effects can also cause anxiety symptoms in the medically ill patient. It is important for the psychiatrist to have knowledge of medications commonly associated with such side effects. Diagnosing primary anxiety disorders, such as generalized anxiety disorder, panic disorder, or posttraumatic stress disorder, can be difficult in medically ill patients, but it is an important skill for the consulting psychiatrist. Anxiety can occur secondary to the stress or fear associated with illness, particularly serious illness. This presentation will discuss all of the aforementioned aspects of anxiety in the patient with concomitant medical illness.

Anti-Anxiety Agents↗
PubMed1992

Psychopharmacology in the elderly.

By the year 2030, it is estimated that 17% of the population (52 million people) will be over age 65. Most of these individuals will be taking several medications, and one or more of these medications may be a psychotropic, that is, an antidepressant, anxiolytic, antipsychotic, or lithium. This article summarizes the pharmacokinetic changes that accompany aging and highlight how these changes impact the elderly.

Age Factors↗
PubMed1990

Psychiatric disorders in the medically ill.

Psychiatric disorders commonly coexist in patients with medical illness. Three disorders encountered frequently are anxiety disorders, depression, and delirium. The authors discuss these psychiatric disorders and their treatment in medically ill patients. Psychiatric consultation may be helpful in such cases.

Anxiety↗
PubMed1990

Anxiety and mood disorders in medically ill patients.

In medically ill patients, anxiety symptoms and mood alteration are common. Anxiety or mood alteration may be due to a reaction to the stress of illness, a preexisting psychiatric disorder, a manifestation of the medical condition, or an adverse effect of medication. Psychiatrists are frequently called upon to differentiate among these causes and to recommend treatment. This article reviews anxiety, depression, and mania, which are frequently associated with physical disease, and provides an approach to differential diagnosis and treatment.

Antidepressive Agents↗
PubMed1989

Choreoathetosis: a sign of lithium toxicity.

Two patients who developed choreoathetosis in the course of lithium treatment are described, and other cases of choreoathetosis in lithium-treated patients are reviewed. Choreoathetosis is suggested to be a sign of lithium toxicity, almost always accompanied by other signs of neurotoxicity, such as delirium and cerebellar dysfunction. Of the reported cases, 44% developed permanent movement disorders, and 63% of the patients with permanent deficits were taking both lithium and neuroleptic. When choreoathetosis was not permanent, the average duration was seven days after discontinuation of lithium (range, 1 to 90 days).

Aged↗
PubMed1989

Causes of organic mood disorder.

A retrospective review of the records of 755 patients seen by a psychiatric consultation-liaison service in a general hospital was performed. The authors found that 87% of manic patients and 38% of depressed patients had a diagnosis of organic mood disorder. The most frequent precipitants of mania were corticosteroids, human immunodeficiency virus (HIV) infection, and temporolimbic epilepsy. The most frequent precipitants of depression were stroke, Parkinson's disease, and HIV infection.

Bipolar Disorder↗