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1.
Biol Lett ; 20(7): 20240177, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38982849

ABSTRACT

While various marine predators form associations, the most commonly studied are those between subsurface predators and seabirds, with gulls, shearwaters or terns frequently co-occurring with dolphins, billfish or tuna. However, the mechanisms underlying these associations remain poorly understood. Three hypotheses have been proposed to explain the prevalence of these associations: (1) subsurface predators herd prey to the surface and make prey accessible to birds, (2) subsurface predators damage prey close to the surface and thereby provide food scraps to birds, and (3) attacks of underwater predators lower the cohesion of prey groups and thereby their collective defences making the prey easier to be captured by birds. Using drone footage, we investigated the interaction between Indo-Pacific sailfish (Istiophorus platypterus) and terns (Onychoprion sp.) preying on schooling fish off the eastern coast of the Malaysian peninsula. Through spatio-temporal analysis of the hunting behaviour of the two predatory species and direct measures of prey cohesion we showed that terns attacked when school cohesion was low, and that this decrease in cohesion was frequently caused by sailfish attacks. Therefore, we propose that sailfish created a by-product benefit for the bird species, lending support to the hypothesis that lowering cohesion can facilitate associations between subsurface predators and seabirds.


Subject(s)
Predatory Behavior , Animals , Charadriiformes/physiology , Fishes/physiology , Malaysia , Food Chain , Birds/physiology , Feeding Behavior
2.
Philos Trans R Soc Lond B Biol Sci ; 378(1878): 20220103, 2023 06 05.
Article in English | MEDLINE | ID: mdl-37066648

ABSTRACT

The open ocean offers a suite of ecological conditions promoting the occurrence of multi-species predator aggregations. These mixed predator aggregations typically hunt large groups of relatively small and highly cohesive prey. However, the mechanisms and functions of these mixed predator aggregations are largely unknown. Even basic knowledge of whether the predator species' interactions are mutualistic, commensal or parasitic is typically missing. Moreover, recordings of attack and capture rates of marine multi-species predator aggregations, which are critical in understanding how and why these interactions have evolved, are almost completely non-existent owing to logistical challenges. Using underwater video, we quantified the attack and capture rates of two high-trophic level marine predators, California sea lions (Zalophus californianus) and striped marlin (Kajikia audax) attacking schools of fishes in the Southern California Current System, offshore the Baja California Peninsula. Recording over 5000 individual attacks across 13 fish schools, which varied in species, size and predator composition, we found that sea lions kleptoparasitized striped marlin hunts and reduced the frequency of marlin attacks and captures via interference competition. We discuss our results in the context of the phenotypic differences between the predator species and implications for a better understanding of multi-species predator aggregations. This article is part of the theme issue 'Mixed-species groups and aggregations: shaping ecological and behavioural patterns and processes'.


Subject(s)
Perciformes , Predatory Behavior , Sea Lions , Animals , Fishes , Mexico
3.
Z Rheumatol ; 71(10): 841-9, 2012 Dec.
Article in German | MEDLINE | ID: mdl-22932980

ABSTRACT

Rheumatoid arthritis (RA) represents an autoimmune disease affecting mostly joints, in particular small finger and toe joints. In addition RA can show extra-articular manifestations in many organs. Information on the frequency of extra-articular manifestations (EAMs) in RA varies greatly in different publications from 17.8% to 40.9% and EAMs tend to become higher with increasing duration and severity of the disease. The exact etiology and pathogenesis are still unclear but vasculitic alterations together with deposition of immune complexes can often be found histopathologically in affected organs. It must also be taken into consideration that EAMs can also be a result of the pharmaceutical therapy. The organ findings can vary greatly which is also reflected in the multitude of clinical symptoms. Possible target organs are the blood vessels, kidneys, central nervous system, cardiovascular system, the lungs, eyes, skin, nails as well as blood and the hemopoetic system. The prognosis for RA becomes progressively worse in the presence of EAMs. Regular and continuous control investigations are necessary in order to be able to diagnose EAMs early and to begin therapy. Therapy includes the administration of non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs) and especially in advanced stages cyclophosphamide or biologicals. Therapy is still very empirical due to the lack of appropriate studies.


Subject(s)
Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/epidemiology , Brain Diseases/epidemiology , Cardiovascular Diseases/epidemiology , Hematologic Diseases/epidemiology , Kidney Diseases/epidemiology , Skin Diseases/epidemiology , Biological Products/therapeutic use , Brain Diseases/drug therapy , Cardiovascular Diseases/drug therapy , Comorbidity , Hematologic Diseases/drug therapy , Humans , Incidence , Kidney Diseases/drug therapy , Prognosis , Risk Factors , Skin Diseases/drug therapy
4.
Z Rheumatol ; 71(6): 515-7, 2012 Aug.
Article in German | MEDLINE | ID: mdl-22802026

ABSTRACT

Primary manifestation of an autoinflammatory systemic disease was found in a 15-year-old patient, which initially ran a fulminant course. The course was first controlled by therapy with steroids and cyclosporin A. In the course of the disease, the patient developed a therapy refractory polyarthritis, which failed to respond to a combination of disease-modifying antirheumatic drugs (DMARDs) and tumor necrosis factor (TNF) inhibitors. A good disease control could only be achieved with an interleukin 6 (IL-6) blockade and DMARDs.


Subject(s)
Arthritis/diagnosis , Arthritis/therapy , Cyclosporine/therapeutic use , Fever/diagnosis , Fever/therapy , Steroids/therapeutic use , Adolescent , Anti-Asthmatic Agents/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Arthritis/complications , Fever/complications , Humans , Male , Treatment Failure , Treatment Outcome
5.
J Hered ; 94(2): 133-47, 2003.
Article in English | MEDLINE | ID: mdl-12721225

ABSTRACT

The population structure of Anopheles gambiae in Africa was studied using 11 microsatellite loci in 16 samples from 10 countries. All loci are located outside polymorphic inversions. Heterogeneity among loci was detected and two putative outlier loci were removed from analyses aimed at capturing genome-wide patterns. Two main divisions of the gene pool were separated by high differentiation (F(ST) > 0.1). The northwestern (NW) division included populations from Senegal, Ghana, Nigeria, Cameroon, Gabon, Democratic Republic of Congo (DRC), and western Kenya. The southeastern (SE) division included populations from eastern Kenya, Tanzania, Malawi, and Zambia. Inhospitable environments for A. gambiae along the Rift Valley partly separate these divisions. Reduced genetic diversity in the SE division and results of an analysis based on private alleles support the hypothesis that a recent bottleneck, followed by colonization from the NW populations shaped this structure. In the NW division, populations possessing the M rDNA genotype appeared to form a monophyletic clade. Although genetic distance increased with geographic distance, discontinuities were suggested between certain sets of populations. The absence of heterozygotes between sympatric M and S populations in the DRC and the high differentiation in locus 678 (F(ST)>0.28) contrasted with low differentiation in all other loci (-0.02

Subject(s)
Anopheles/genetics , Genetics, Population , Africa South of the Sahara , Animals , Genetic Variation , Homozygote , Microsatellite Repeats , Phylogeny
6.
Mol Biol Evol ; 18(7): 1353-64, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11420373

ABSTRACT

Gene flow in malaria vectors is usually estimated based on differentiation indices (e.g., F(ST)) in order to predict the contemporary spread of genes such as those conferring resistance to insecticides. This approach is reliant on a number of assumptions, the most crucial, and the one most likely to be violated in these species, being mutation-migration-drift equilibrium. Tests of this assumption for the African malaria vectors Anopheles gambiae and Anopheles arabiensis are the focus of this study. We analyzed variation at 18 microsatellite loci and the ND5 region of the mitochondrial genome in two populations of each species. Equilibrium was rejected by six of eight tests for the A. gambiae population from western Kenya and by three tests in eastern Kenya. In western Kenya, all departures from equilibrium were consistent with a recent population expansion, but in eastern Kenya, there were traces of a recent expansion and a bottleneck. Equilibrium was also rejected by two of the eight tests for both A. arabiensis populations; the departure from equilibrium was consistent with an expansion. These multiple-locus tests detected a genomewide effect and therefore a demographic event rather than a locus-specific effect, as would be caused by selection. Disequilibrium due to a recent expansion in these species implies that rates of gene flow, as inferred from differentiation indices, are overestimates as they include a historical component. We argue that the same effect applies to the majority of pest species due to the correlation of their demography with that of humans.


Subject(s)
Anopheles/genetics , Insect Vectors/genetics , Africa , Animals , DNA, Mitochondrial/genetics , Evolution, Molecular , Genetics, Population , Humans , Malaria/transmission , Microsatellite Repeats , Models, Genetic , Mutation , Polymorphism, Genetic , Species Specificity
10.
Nephrol News Issues ; 15(5): 42, 46-8, 50, 2001 Apr.
Article in English | MEDLINE | ID: mdl-12108962

ABSTRACT

This article describes one renal disease management organization's experience in implementing a pre-dialysis care management program to improve outcomes in patients who develop end-stage renal disease (ESRD). Optimal Renal Care, a national renal disease management company, has implemented care management programs for 600+ ESRD patients and 600+ pre-ESRD patients in Oregon (1998) and Hawaii (1999). This article describes our Oregon pre-ESRD program's start-up experience.


Subject(s)
Disease Management , Kidney Failure, Chronic/therapy , Patient Care Planning , Renal Dialysis , Humans , Patient Advocacy , Patient Care Team , Patient Education as Topic , Patient Selection , Program Development , Treatment Outcome
11.
Fertil Steril ; 72(4): 666-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10521107

ABSTRACT

OBJECTIVE: To study the effect of in vitro culture on the quality of human testicular sperm and the efficiency of intracytoplasmic sperm injection with in vitro cultured testicular sperm. DESIGN: Clinical study. SETTING: A private IVF center. PATIENT(S): Twenty consecutively seen IVF patients undergoing testicular biopsies for ICSI. INTERVENTION(S): The testicular specimens were cultured in vitro for 24 hours and the isolated spermatozoa were microinjected. MAIN OUTCOME MEASURE(S): Preincubation and postculture sperm motility, and fertilization, implantation, and pregnancy rates after intracytoplasmic sperm injection. RESULT(S): Motility increased from initial nonmotile or twitching sperm to free motile sperm in 18 of 20 cases. The injection of in vitro cultured testicular sperm resulted in a fertilization rate of 58%, an implantation rate of 20%, and a pregnancy rate of 45%. CONCLUSION(S): A testicular biopsy procedure can be performed the day before egg retrieval. Despite the low initial sperm quality, a high percentage of the prepared testicular sperm showed increased motility after 24 hours of culture. The injection of in vitro cultured testicular sperm into matured oocytes resulted in fertilization, implantation, and pregnancy rates comparable to those obtained with ejaculated sperm.


Subject(s)
Oocytes , Sperm Injections, Intracytoplasmic , Spermatozoa , Tissue and Organ Harvesting , Adult , Cells, Cultured , Embryo Implantation , Female , Fertilization , Humans , Male , Pregnancy , Pregnancy Rate , Sperm Motility , Spermatozoa/physiology , Testis , Time Factors
12.
Clin Nucl Med ; 24(10): 781-3, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10512105

ABSTRACT

PURPOSE: To assess the use of a Tc-99m erythrocyte-labeled SPECT scan to characterize a giant splenic hemangioma. METHODS: A patient clinically mistaken to have a myelodysplastic disorder underwent a contrast-enhanced CT followed by a Tc-99m erythrocyte-labeled SPECT scan. RESULTS: CT showed a heterogeneous vascular lesion arising in the spleen. Percutaneous biopsy was nondiagnostic. A Tc-99m erythrocyte-labeled SPECT study revealed findings consistent with a giant splenic hemangioma, which was subsequently confirmed at surgery. CONCLUSION: A Tc-99m erythrocyte-labeled SPECT scan may be very useful in confirming the diagnosis of a large or giant splenic hemangioma.

14.
Compr Ther ; 25(2): 90-4, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10091013

ABSTRACT

Erectile dysfunction is a common problem affecting men. Sildenafil (Viagra) is the first oral medication approved for the treatment of erectile dysfunction. It has proven to be an effective option in the treatment of erectile dysfunction of different etiologies.


Subject(s)
Erectile Dysfunction/drug therapy , Phosphodiesterase Inhibitors/therapeutic use , Piperazines/therapeutic use , Clinical Trials as Topic , Contraindications , Drug Synergism , Erectile Dysfunction/physiopathology , Humans , Hypotension/chemically induced , Male , Nitrates/adverse effects , Penile Erection/drug effects , Penile Erection/physiology , Phosphodiesterase Inhibitors/pharmacology , Piperazines/pharmacology , Purines , Sildenafil Citrate , Sulfones
15.
Cleve Clin J Med ; 65(6): 301-4, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9637957

ABSTRACT

Sildenafil, the first oral drug for treating male erectile dysfunction, appears effective and well tolerated. However, more time and experience will be needed to establish this drug's true efficacy and safety.


Subject(s)
Enzyme Inhibitors/therapeutic use , Erectile Dysfunction/drug therapy , Piperazines/therapeutic use , Enzyme Inhibitors/pharmacology , Humans , Male , Penis/drug effects , Piperazines/pharmacology , Purines , Sildenafil Citrate , Sulfones , Treatment Outcome
16.
Proc Natl Acad Sci U S A ; 95(8): 4425-30, 1998 Apr 14.
Article in English | MEDLINE | ID: mdl-9539753

ABSTRACT

We have analyzed DNA sequences from world-wide geographic strains of Plasmodium falciparum and found a complete absence of synonymous DNA polymorphism at 10 gene loci. We hypothesize that all extant world populations of the parasite have recently derived (within several thousand years) from a single ancestral strain. The upper limit of the 95% confidence interval for the time when this most recent common ancestor lived is between 24,500 and 57,500 years ago (depending on different estimates of the nucleotide substitution rate); the actual time is likely to be much more recent. The recent origin of the P. falciparum populations could have resulted from either a demographic sweep (P. falciparum has only recently spread throughout the world from a small geographically confined population) or a selective sweep (one strain favored by natural selection has recently replaced all others). The selective sweep hypothesis requires that populations of P. falciparum be effectively clonal, despite the obligate sexual stage of the parasite life cycle. A demographic sweep that started several thousand years ago is consistent with worldwide climatic changes ensuing the last glaciation, increased anthropophilia of the mosquito vectors, and the spread of agriculture. P. falciparum may have rapidly spread from its African tropical origins to the tropical and subtropical regions of the world only within the last 6,000 years. The recent origin of the world-wide P. falciparum populations may account for its virulence, as the most malignant of human malarial parasites.


Subject(s)
Genes, Protozoan , Malaria, Falciparum/parasitology , Phylogeny , Plasmodium falciparum/genetics , Plasmodium/genetics , Polymorphism, Genetic , Africa , Animals , Asia , Climate , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Demography , Evolution, Molecular , Humans , Life Cycle Stages , Malaria/parasitology , Netherlands , Plasmodium/classification , Plasmodium falciparum/classification , Plasmodium falciparum/physiology , South America , Tetrahydrofolate Dehydrogenase/genetics , Time
17.
J Urol ; 158(2): 460-3, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9224323

ABSTRACT

PURPOSE: We describe a surgical modification of the Nesbit procedure to correct Peyronie's disease, and compare the results of this procedure with those of 2 other surgical techniques. MATERIALS AND METHODS: In 30 patients a vertical incision in the tunica albuginea was closed in a horizontal fashion with permanent suture knots buried beneath the tunica in a running looped fashion, resulting in watertight closure with no exposed suture material. A standard Nesbit procedure and plaque excision with a polyethylene terephthalate mesh reinforced silicone sheet patch graft were done in 28 cases each. RESULTS: Elimination of penile curvature, patient satisfaction and postoperative impotence rates were not statistically different for standard and modified Nesbit procedures. However, plaque excision and synthetic patch grafting resulted in less elimination of curvature (61%, p = 0.004), a lower rate of satisfaction (30%, p = 0.00002) and a higher incidence of impotence after surgery (18%, p = 0.04). The modified Nesbit procedure achieved an overall higher rate of correction of curvature than the standard approach (93 versus 79%). CONCLUSIONS: A modified Nesbit procedure achieves the greatest functional success for Peyronie's disease with an acceptably low complication rate.


Subject(s)
Penile Induration/surgery , Adolescent , Adult , Aged , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Surgical Procedures, Operative/methods , Treatment Outcome
18.
J Urol ; 154(5): 1740-3, 1995 Nov.
Article in English | MEDLINE | ID: mdl-7563336

ABSTRACT

PURPOSE: We evaluated the relative use of RigiScan measurement of radial rigidity compared to sleep laboratory measurement of axial rigidity and trained observer determination of erectile function in the diagnosis of organic impotence. MATERIALS AND METHODS: A total of 28 patients underwent simultaneous 2-night formal sleep laboratory nocturnal penile tumescence and RigiScan monitoring. Standard normal values for radial rigidity and axial rigidity were tested for accuracy in predicting normal nocturnal penile tumescence compared to trained observer determination of the adequacy of an erection for penetration. RESULTS: RigiScan tip measurements correlated poorly with buckling pressure, while base measurements strongly correlated (p = 0.0005). Observer determination of a functional erection was strongly associated with tip (p = 0.002), base (p = 0.0005) and buckling pressure measurements (p = 0.0005). Using observer determination as the gold standard receiver operating curves were generated to select RigiScan base and buckling pressure measurements that predicted functional erections with the highest sensitivity and specificity. CONCLUSIONS: RigiScan is a useful tool for measuring nocturnal penile tumescence. However, base measurements are more accurate than tip measurements for evaluating erectile function. The currently accepted level of rigidity used to define a normal erection (70% or greater) overestimates organic erectile dysfunction.


Subject(s)
Erectile Dysfunction/diagnosis , Adult , Aged , Humans , Male , Middle Aged , Penile Erection , Prospective Studies , Sensitivity and Specificity , Sleep
19.
Semin Urol Oncol ; 13(4): 262-6, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8595549

ABSTRACT

Renal adenoma and oncocytoma are relatively common, benign solid renal tumors. These lesions rarely present with specific genitourinary symptoms and are most often incidentally detected as small renal masses. While some radiologic findings are suggestive of either lesion, there are no pathognomonic radiologic features that can dependably differentiate them from renal cell carcinoma. Renal adenoma is often histologically indistinguishable from renal cell carcinoma, and renal oncocytoma shares many cellular features with granular renal cell carcinoma, thereby limiting the utility of needle biopsy or aspiration cytology for diagnosis. These tumors are also often found associated with renal cell carcinoma in the same or contralateral kidney, so that surgical excision is the only reliable means to achieve both definitive diagnosis and treatment.


Subject(s)
Adenoma, Oxyphilic/diagnosis , Adenoma/diagnosis , Kidney Neoplasms/diagnosis , Adenoma/epidemiology , Adenoma/pathology , Adenoma/surgery , Adenoma, Oxyphilic/epidemiology , Adenoma, Oxyphilic/pathology , Carcinoma, Renal Cell/diagnosis , Diagnosis, Differential , Female , Humans , Male , Nephrectomy , Prognosis , Tomography, X-Ray Computed
20.
Urology ; 46(4): 577-80, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7571235

ABSTRACT

Erectile dysfunction can result from blunt or penetrating pelvic or perineal trauma. Rupture of the corpora cavernosa leading to loss of the veno-occlusive mechanism and penile artery occlusion have been found in these patients. We present a case of immediate loss of erectile function after penetrating perineal trauma resulting in corpus cavernosum rupture and traumatic occlusion of multiple arteries in the hypogastric-cavernous bed. Conservative management of the corpus injury resulted in post-traumatic aneurysmal dilation at the site of injury with venous leakage from aberrant veins. Penile arterial revascularization and aneurysm repair with deep penile venous ligation resulted in near-complete return of normal erectile function.


Subject(s)
Aneurysm/surgery , Erectile Dysfunction/surgery , Penis/blood supply , Penis/injuries , Perineum/injuries , Wounds, Penetrating/complications , Adolescent , Aneurysm/etiology , Arteries/surgery , Erectile Dysfunction/etiology , Humans , Ligation , Male , Penis/surgery , Remission Induction , Veins
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