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At least 19 recordsLinked to original sources
PubMed1992

Long-term metabolic effects of urinary diversion: a comparison of myelomeningocele patients managed by clean intermittent catheterization and urinary diversion.

We previously reported that chronic urinary diversion through intestinal segments may have adverse effects on bone and mineral metabolism. This study examined the long-term health of patients managed by urinary diversion (94% by ileal conduit) for neuropathic bladders secondary to myelomeningocele defects and compared them to a control population of myelomeningocele patients managed by intermittent catheterization. Of the patients 93 were studied by personal interview, chart review, morphometric analysis, serum studies and dual-photon bone density determination. Average followup was 23 +/- 6 years in the urinary diversion group and 17 +/- 5 years in the intermittent catheterization group. Fractures occurred in 40% of the patients in both groups. Patients with a urinary diversion had an increased need for surgery to correct spinal curvature (57% versus 40%) and a significantly increased incidence of complications resulting from orthopedic procedures (17% versus 3%, p less than or equal to 0.05). There was also an adverse effect on renal function. The urinary diversion group had an increased incidence of radiographic renal deterioration (57% versus 8%, p less than 0.001), nephrolithiasis (43% versus 2%, p less than 0.001), pyelonephritis (60% versus 21%, p less than 0.001) and intermittent metabolic acidosis (20% versus 5%, p = 0.05). Surgery was required in 37% for stomal complications and in 17% for ureterointestinal stricture. Linear growth was adversely affected by urinary diversion. Patients with urinary diversion had decreased lengths for all morphometric parameters and a greater percentage of them were at or below the 10th percentile standards. Serum electrolytes, liver function studies, vitamin D3 and parahormone showed no differences in the 2 groups. No patient had a significant metabolic acidosis at the time of study. Bone densities were significantly diminished in both groups and not significantly different. This study strongly suggests that urinary diversion through intestinal segments is associated with adverse effects on bone health.

Bone Density↗
PubMed1991

[Urinary de-diversion after diversion with chronic bladder contamination. An experimental study in male rats].

We have carried out an experimental model of urinary diversion and dis-diversion on male Wistar rats in order to study the complications that are produced after diversion, as well as to see whether the alterations continue unchanged, or increase, or diminish after dis-diversion. The following experimental design was used: a control group made up of 48 animals an a problem group of 200 animals all submitted to vesicosigmoidostomy of which 100 were designed to be subsequently dis-diverted. The sacrificed animals (n = 112) were studied for somatic, biochemical and histological parameters. Statistical comparison of the problem group with the controls showed significant differences for the somatic and biochemical parameters, especially in the form of weight-size retardation, increase of urea, creatinine, calcium, phosphorus, uric acid, cholesterol, transaminase, alkaline phosphatase, sodium and chlorine and decrease in albumin and total proteins. After dis-diversion there is an improvement of some of these parameters without reaching total normalization. This leads us to think that either the lesions are irreversible, or more time after dis-diversion is needed for there to be reversibility. We also describe the histological lesions found at the level of the vesicointestinal anastomosis, and the mortality of our series which is higher than that presented by females, a fact inducing us to think that factors exist in the male which increase the mortality.

Animals↗
PubMed1986

Antigenic diversity and size diversity of P. falciparum antigens in isolates from Gambian patients. II. the schizont surface glycoprotein of molecular weight approximately 200 000.

A panel of monoclonal antibodies has been shown previously to identify both serologically diverse and serologically conserved epitopes on a major polymorphic surface protein of P. falciparum schizonts from culture-adapted isolates. The molecular nature of the antigen recognized by eight of these monoclonal antibodies was studied with three isolates analyzed directly from patients in The Gambia. Malarial (glyco) proteins were labelled by biosynthetic uptake of 3H-glucosamine or 3H-leucine during culture of ring-stage parasites from infected blood to the late-trophozoite/early-schizont stage (26-30 h). Those monoclonal antibodies which reacted positively with an isolate by indirect immunofluorescence also immunoprecipitated a single 3H-leucine or 3H-glucosamine labelled antigen of mol. wt approximately 200 000 from Triton X-100 extracts of the same isolate. Monoclonal antibodies which did not react by indirect immunofluorescence failed to immunoprecipitate this antigen. Although each of the three isolates studied in detail was very similar serologically with the panel of monoclonal antibodies specific for this mol. wt approximately 200 000 antigen, this protein could be distinguished with each isolate on the basis of its apparent size on SDS-polyacrylamide gel electrophoresis. The specifically immunoprecipitated antigen had a mol. wt of 204 000, 197 000 or 202 000, depending on the isolate. Size diversity of this malarial glycoprotein was also detected with seven other Gambian P. falciparum isolates. We conclude that natural isolates of P. falciparum express a major 3H-glucosamine labelled glycoprotein of mol. wt Mr approximately 200 000 which exhibits size diversity and expresses antigenically conserved as well as diverse epitopes as defined by the panel of monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1990

Diversity in junctional sequences associated with the common human V gamma 9 and V delta 2 gene segments in normal blood and lung compared with the limited diversity in a granulomatous disease.

The T cell receptor (TCR) junctional regions (N regions) of the common human V gamma 9 and V delta 2 gene segments were sequenced from the blood and lung of normal individuals (195 transcripts) and a group of individuals with sarcoidosis (220 transcripts), a granulomatous disease in which increased numbers of V gamma 9+ gamma/delta + T cells are often observed. In normal individuals, the vast majority (86%) of blood V gamma 9 transcripts used the J gamma P gene segment. In contrast to this restriction of J region usage, there was a large diversity of the junctional region, with less than 20% of blood V gamma 9 junctional regions showing identical sequences for any one normal individual. For the blood V delta 2 transcripts in normal individuals, there was restriction of J region usage, with 93% using J delta 1. The junctional regions were even more diverse than for V gamma 9, with a unique sequence observed in each transcript examined. Compared with blood, sequences from the normal lung showed a small increase in identical junctional regions, particularly in one individual where 46% of V gamma 9 transcripts examined were identical, suggesting a response of some gamma/delta T cells to antigens found in the lung in the normal state. In marked contrast to normals, some individuals with sarcoidosis had large numbers of V gamma 9 transcripts, as well as V delta 2 transcripts, sharing identical sequences. For V gamma 9 blood transcripts, two individuals showed 84 and 56% of junctional region sequences to be identical, respectively. Similarly, blood V delta 2 transcripts showed 43, 33, and 25% identical junctional region sequences in three individuals. In the sarcoid patient with the most striking over-representation of blood V gamma 9 junctional sequences, lung V gamma 9 transcripts showed increased (67%) use of the same junctional region sequence as in blood. This limited diversity of TCR junctional regions among some individuals with sarcoidosis suggests a response from specific stimuli, possibly antigenic, and that gamma/delta T cells may play a specific role in granuloma formation in sarcoidosis, as has been suggested in other granulomatous diseases.

Adult↗
PubMedDate not supplied

Genetic diversity of Plasmodium falciparum in a village in eastern Sudan. 1. Diversity of enzymes, 2D-PAGE proteins and antigens.

Twenty-nine plasmodium falciparum isolates from patients in Asar village, eastern Sudan, were characterized for variation in 18 different genetically controlled characters, including iso-enzymes, proteins detected by two-dimensional polyacrylamide gel electrophoresis and blood-stage antigens. Considerable allelic diversity in the genes determining these characters was detected. Each isolate contained genetically distinct parasites. Fifteen individuals were infected with more than one parasite genotype. The diversity of parasite types is most probably generated by recombination during mosquito transmission of mixed parasite clones.

Animals↗
PubMed1986

Antigenic diversity and size diversity of Plasmodium falciparum antigens in isolates from Gambian patients. I. S-antigens.

Ring-stage asexual parasites of P. falciparum were collected from six Gambian children and the S-antigens radiolabelled by 3H-glycine uptake during in vitro culture up to rupture of infected cells and merozoite release. Ouchterlony double diffusion of boiled culture supernatants against a panel of adult Gambian sera identified one S-antigen precipitin arc for five isolates and two precipitin arcs for one isolate. Five of the six isolates were serologically distinct. Analysis of S-antigens by comparison of SDS-polyacrylamide gel electrophoresis patterns of heat-treated soluble proteins revealed a more complex pattern of 3H-labelled S-antigens that was different for each isolate. There were between two and six different 3H-labelled bands for each isolate in the size range of molecular weight 137 000 to 285 000. This result confirms the large size range of S-antigens identified with culture adapted P. falciparum. Several bands were relatively weakly labelled with 3H-glycine, suggesting that natural isolates contain one or two predominant S-antigen phenotypes and several other S-antigen phenotypes expressed by minor parasite subpopulations. Immunoprecipitation was performed using a panel of sera from Gambian adults, or, acute and 3 week convalescent sera from the same patients used for S-antigen radiolabelling. Adult sera generally immunoprecipitated some of the S-antigens in each isolate, including antigens that must represent extremely minor parasite subpopulations since they could not be seen in the patterns of non-immunoprecipitated heat-stable proteins. Sera from convalescent children were generally negative on immunoprecipitation, even with the homologous isolate. In one case we observed the acquisition of specific immunoprecipitating antibody to one of the homologous S-antigens during the convalescent period. The antigenic and structural complexity of S-antigens in natural isolates that have not been submitted to the selection pressure of adaptation for in vitro culture is clearly greater than for culture adapted P. falciparum.

Adult↗
PubMed1992

Diversity in nursing faculty hinges on diversity in nursing students.

In this chapter, I attempted to explicate and highlight some of the interrelationships which exist in higher education between white male and female faculty members from a minority perspective. I discussed the effect of attitudes on the success of minority students and faculty in light of projected demographic changes. I hope that white female faculty members will become more cognizant of how negative attitudes impact upon both their own performance in higher education and also how the inculcation of these attitudes can be transferred to minority faculty members with devastating results. Change is difficult in all spheres of life, but without some modicum of change, life will go on as usual. Minority faculty members and students deserve at the very least a fair chance in the game we call higher education.

Black or African American↗
PubMed1976

Cultural diversity in central America and Panama: its relationship to conservation and planning.

The most frequently overlooked aspect of conservation of natural resources and economic development is human cultural diversity. However, conservation and development of natural resources are basically human-oriented endeavors and all conservation and developmental efforts ought to start with a clear understanding of the varied needs of the people. In addition, cultural diversity is a natural resource that ought to be protected along with all the more commonly recognized resources of the ecosystems of which humans form an integral part. Cultural diversity in a large measure is an ecological phenomenon because such diversity includes variations in the ways different people perceive and utilize the environments in which they live. Thus, cultural diversity, in large measure, equates with ecological diversity. It has been well established that a high degree of ecological diversity (including taxonomic, niche, biogeochemical and other measures of diversity) is a necessary attribute of humid tropical ecosystems if such ecosystems are to remain viable over long periods of time. The current land-use trends in Central America and Panama are leading toward ever larger areas being devoted to monocultural use with sharply reduced ecological diversity that poses great dangers for the near and long terms. In addition, the resultant removal of people from rural areas results in growing social, economic and political problems, that are not being successfully met by developing nations. Not only is there a growing wastage of human resources, a weakening of the social structures, and an increasing and dangerous dependence upon monocultures oriented toward export markets, but the ecological diversity of the previous existing land-use systems are being lost. This kind of diversity is probably no less valuable to the ecological health of a nation's agriculture, forestry, and general resource utilization than is the genetic diversity of "primitive" crop plant varieties which biologists now recognize and increasingly seek to preserve as "modern" crop plant varieties become ever more simple genetically and hence ever more vulnerable to disease and other perturbations.

Agriculture↗
PubMed2026

Metagenomic Insights Into Microbial Diversity of Tea Rhizosphere of the Kangra Valley.

This study provides the first metagenomic assessment of microbial diversity from the tea rhizosphere of the Kangra valley. Tea rhizosphere soil samples were collected from 4 locations (Dharamshala, Baijnath, Palampur, and Joginder Nagar) of the Kangra valley. DNA extracts of rhizosphere samples were analysed for bacterial and Archaeal diversity using amplicon sequencing (V3-V4) region of the 16S rRNA gene and Fungal diversity using ITS1 and ITS2 regions. Baijnath and Palampur samples showed the highest bacterial richness, while Dharamshala and Palampur had the highest fungal richness. Proteobacteria was a dominant phylum in all the rhizosphere samples, followed by Firmicutes, Actinobacteria, Acidobacteria, and Bacteroidetes. A total of 11 fungal phyla were identified among all the locations, with abundance of Ascomycota and Basidiomycota. For the Archaea domain, uncultured archaeon and Aeropyrum camini were the most common found among all the locations. A small fraction (<&#x2009;0.5%) of Bacillus and Pseudomonas species were observed among all the locations. Alpha and beta diversity indices displayed notable differences within and between microbial diversities. Soil factors were variably associated with microbial diversity, with nitrogen positively aligned with fungal diversity, while EC and K were associated with Archaeal diversity. Soil pH and OM% showed moderate associations with bacterial diversity. These findings provided valuable and comprehensive insights into tea rhizosphere microbial ecology and could be used to better understand microbial functions and their role in plant health.

Rhizosphere↗
PubMed2026

Spatial scaling of metagenomic diversity reveals ecological disruption in the gut microbiome of gout patients.

Gout, a painful inflammatory arthritis, is characterized by hyperuricemia and monosodium urate crystal deposition, with growing evidence linking its pathogenesis to gut microbiome dysbiosis. However, traditional diversity metrics fail to capture the complex spatial organization of microbial communities. This study addresses this gap by applying the novel metagenomic Diversity-Area Relationship (m-DAR) model to investigate scaling laws in the gout microbiome-quantifying how metagenomic diversity changes with the number of individuals sampled. Our analysis of gut microbiomes from gout patients and healthy controls revealed fundamental ecological disruptions. We found that gout microbiomes exhibited significantly altered scaling patterns: they showed greater inter-individual dissimilarity (higher z-values) at the level of rare genes (q&#x2009;=&#x2009;0), but weaker scaling of dominant genes (q&#x2009;=&#x2009;1-3) compared to healthy controls. Crucially, the maximal accrual diversity (MAD) was substantially lower in gout patients, indicating a severely constrained potential for total microbial gene diversity. Furthermore, profiling of metagenomic functional gene clusters (MFGCs) uncovered widespread functional perturbations, including increased diversity scaling for carbohydrate-active enzymes (CAZy) but decreased scaling in essential metabolic pathways (KEGG, KO). These results demonstrate that the gout gut microbiome is defined by a loss of ecological structure, featuring reduced homogeneity in dominant taxa, expanded rare biosphere variation, and an overall collapsed diversity capacity. This work introduces an ecological framework for characterizing dysbiosis in gout that complements traditional diversity metrics and may inform the development of microbiome-based therapeutic strategies. Further research is needed to translate these ecological patterns into clinical applications.

Humans↗
PubMed1987

Cutaneous ureterostomy as palliative diversion in adults with malignancy.

Over a twenty-one-year period (1963-1984) 46 patients underwent a permanent urinary diversion using cutaneous ureterostomy. Thirty-seven of these patients had this method of diversion employed as palliation for pelvic malignancies. In 70 per cent of the patients diversion was done secondary to ureteral obstruction and in the other patients because of either severe lower urinary tract symptoms or a failed alternate form of diversion. Forty-nine per cent of the patients experienced a postoperative complication. The late postoperative complications were either related to the choice of diversion or presumed progression of the patient's disease. Palliative diversion is now best initially attempted with percutaneous nephrostomy or indwelling ureteral stents if bladder function allows. Cutaneous ureterostomy no longer is indicated as a primary form of palliative diversion, however, it may be used as an alternative to open nephrostomy tube placement or intestinal conduit should other more conservative forms of management fail. The presence of at least one dilated ureter is a prerequisite to the success of this form of diversion.

Adult↗
PubMed1988

Urinary diversion in gynecologic malignancies.

A variety of methods for urinary diversion are employed in patients with gynecologic malignancies depending on whether there is an obstruction or fistula formation due to either tumor growth or radiotherapeutic injury. Percutaneous nephrostomy (PCN) has a low complication rate and is a good method for palliative urinary diversion or may precede some form of permanent diversion to restore the kidney function first. Indication for palliative diversion in tumor obstruction depends on many individual factors. A relative contraindication is tumor progression during therapy. 6-month survival was about 70% in patients with previously untreated tumors or recurrences. This rate is far better than reported in earlier studies, so that a palliative diversion has to be considered for these patients. Also a high rate of recanalization after therapy could be observed in the untreated group, allowing the PCN to be removed. However, this has not been shown to be a prognostic factor. In the individual patient some other aspects, such as quality of life and social status, have to be taken into account before a final decision can be made. Ureteral obstruction after radiotherapy is a rare finding and often mistaken for a more likely recurrence. Different methods to restore the urinary tract, such as reimplantation of the ureter, should be used as a first choice. When the stenosis is due to radiocystitis, enterocytoplasty will often be indicated. Diversion has then to be omitted. The poor quality of life because of permanent incontinence due to fistula formation makes diversion mandatory even if life expectancy is very short. Surgical closure of a large radiogenic fistula is rarely successful. In this situation, ileal conduit has proven its efficacy for long-term urinary diversion.

Female↗
PubMed2026

PaNDA: Efficient Optimization of Phylogenetic Diversity in Networks.

Phylogenetic diversity (PD) plays an important role in biodiversity, conservation, and evolutionary studies by measuring the diversity of a set of taxa based on their phylogenetic relationships. In phylogenetic trees, a subset of k taxa with maximum PD can be found by a simple and efficient greedy algorithm. However, this algorithmic tractability is lost when considering phylogenetic networks, which incorporate reticulate evolutionary events such as hybridization and horizontal gene transfer. To address this challenge, we introduce PaNDA (Phylogenetic Network Diversity Algorithms), the first software package and interactive graphical user-interface for exploring, visualizing, and maximizing diversity in phylogenetic networks. PaNDA includes a novel algorithm to find a subset of k taxa with maximum diversity, running in polynomial time for networks of bounded scanwidth, a measure of tree-likeness of a network that grows slower than the well-known level measure. This algorithm considers the variant of PD on networks in which the branch lengths of all paths from the root to the selected taxa contribute towards their diversity. We demonstrate the scalability of this algorithm on simulated networks, successfully analyzing level-15 networks with up to 200 taxa in seconds. We also provide a proof-of-concept analysis using a phylogenetic network on Xiphophorus species, illustrating how the tool can support diversity studies based on real genomic data. The software is easily installable and freely available at https://github.com/nholtgrefe/panda. Additionally, we extend the definition of PD to semi-directed phylogenetic networks, which are mixed graphs increasingly used in phylogenetic analysis to model uncertainty of the root location. We prove that finding a subset of k taxa with maximum diversity remains NP-hard on semi-directed networks, but do present a polynomial-time algorithm for networks with bounded level.

network↗
PubMed2025

Temporal Genomics Reveal a Century of Genomic Diversity Shifts Across a Biodiversity Hotspot Avian Assemblage.

Biodiversity has experienced tremendous shifts in community, species, and genetic diversity during the Anthropocene. Understanding temporal diversity shifts is especially critical in biodiversity hotspots, i.e., regions that are exceptionally biodiverse and threatened. Here, we use museomics and temporal genomics approaches to quantify temporal shifts in genomic diversity in an assemblage of eight generalist highland bird species from the Ethiopian Highlands (part of the Eastern Afromontane Biodiversity Hotspot). With genomic data from contemporary and historical samples, we demonstrate an assemblage-wide trend of increased genomic diversity through time, potentially due to improved habitat connectivity within highland regions. Genomic diversity shifts in these generalist species contrast with general trends of genomic diversity declines in specialist or imperiled species. In addition to genetic diversity shifts, we found an assemblage-wide trend of decreased realized mutational load, indicative of overall trends for potentially deleterious variation to be masked or selectively purged. Across this avian assemblage, we also show that shifts in population genomic structure are idiosyncratic, with species-specific trends. These results are in contrast with other charismatic and imperiled African taxa that have largely shown strong increases in population genetic structure over the recent past. This study highlights that not all taxa respond the same to environmental change, and generalists, in some cases, may even respond positively. Future comparative conservation genomics assessments on species groups or assemblages with varied natural history characteristics would help us better understand how diverse taxa respond to anthropogenic landscape changes.

Animals↗
PubMed1990

Comparison of phenotypic diversity and DNA heterogeneity in a population of soil bacteria.

The phenotypic diversity of about 200 bacterial strains isolated from soil was compared with the genotypic diversity of the same population. The strains were phenotypically characterized by the API 20B test system. The results of these tests were subjected to cluster analysis, which revealed 41 biotypes at 80% similarity. The five dominating biotypes contained 43% of the strains. The phenotypic diversity as determined by the Shannon index, equitability, rarefaction, and cumulative differences was high, but indicated some dominant biotypes. The genetic diversity was measured by reassociation of mixtures of denatured DNA isolated from the bacterial strains (C0t plots). The observed genetic diversity was high. Reassociation of DNA from all bacterial strains together revealed that the population contained heterologous DNA equivalent to 20 totally different bacterial genomes (i.e., genomes that have no homology). This study showed that reassociation of DNA isolated from a collection of bacteria gave a good estimate of the diversity of the collection and that there was good agreement with different phenotypic diversity measures. The Shannon index in particular has features in common with the genetic diversity measure presented here.

Bacteria↗