Antibiotic resistance in bacterial urinary tract infections, 1991 to 1997

This study assessed changing patterns of antibiotic resistance in Escherichia coli urinary tract infections at a university student health center during three periods: the first 6 months each of 1991, 1994, and 1997. Urine culture and sensitivity results were taken from available medical records of female patients having urine cultures during the three periods (1991, n = 739; 1994, n = 938; 1997, n = 863); age and ethnicity were also noted. In E. coli isolates (the majority of positive cultures), resistance to four antibiotics changed significantly: ampicillin (30% to 45% to 39%), carbenicillin (29% to 42% to 39%), tetracycline (29% to 40% to 23%), and trimethoprim/sulfamethoxazole (15% to 32% to 15%). The results raise questions regarding the future clinical reliability of several commonly used antibiotics in the treatment of urinary tract infection.     

Isolation of putative plant transcriptional coactivators using a modified two-hybrid system incorporating a GFP reporter gene

Liver and spleen volumes and serum concentrations of nitrate (the end-product of NO in vivo), albumin, gamma-globulin, protein, creatine and urea were measured during the course of progressive infections with Leishmania infantum MON-1 (MHOM/PR/93/CRE29) in 10 Syrian golden hamsters. Each hamster was infected by intraperitoneal injection with 4 x 10(7) promastigotes. Five of the infected animals were treated, with 6 mg liposomal amphotericin B (L-AmB)/kg given by intracardiac injection, on day 107 post-infection (p.i.). Compared with those in the uninfected hamsters used as controls, the liver volumes in the infected animals became significantly enlarged by day 40 p.i. (38% larger than the controls; P < 0.001) whereas significant enlargement of the spleen was first detected on day 72. Each infected animal had detectable serum levels of antileishmanial antibodies on day 72. There were significant elevations in gamma-globulin concentration as early as day 40 (P < 0.05) but significant falls in albumin concentrations were only detected from day 107 (P < 0.001). Nitrate, creatinine and urea concentrations remained unchanged during the course of infection, even after L-AmB treatment. Serum nitrate levels were not enhanced by L. infantum infection nor by the L-AmB treatment which induced a 98.2% decrease in parasite burden. The lack of NO production in visceral leishmaniasis, with or without L-AmB treatment, points to the unresponsiveness of inducible nitric oxide synthase in this rodent model.     

Chronic intestinal pseudoobstruction associated with fetal alcohol syndrome

Alcohol acts as a teratogen in the fetus, resulting in prenatal or postnatal growth failure, characteristic facial dysmorphic features, and central nervous system dysfunction. The toxic effects of alcohol on the developing brain are well recognized, but gastrointestinal neuropathy has not been described in fetal alcohol syndrome (FAS). Five children with FAS presented in infancy with signs and symptoms suggestive of chronic intestinal pseudoobstruction. They were not able to sustain adequate caloric intake by mouth, and all required prolonged special methods of alimentation. We performed antroduodenal manometry in these children to determine whether their symptoms were associated with a gastrointestinal motility disorder. All patients had abnormally propagating phase III-like episodes during fasting (retrograde in four, simultaneous in two). Persistent clusters of stationary contractions were a prominent feature in two patients. In utero neurotoxicity of alcohol may not be limited to the central nervous system, but may also cause an enteric neuropathy presenting in infancy as chronic intestinal pseudoobstruction.     

Prions and neurodegenerative human diseases

The aim of our investigations was to elucidate some immune aspects of combination of caries and periodontitis with periodic disease (PD), also known as familial Mediterranean fever. In this regard in patients with active and non-active stage of PD we have studied dynamic changes of concentration of secretory immunoglobulin A (SIgA) in saliva and phagocytic activity of neutrophils derived from gum blood. It has been shown that in patients with PD these indices of local immunity of oral cavity had tendency to a decrease especially in case of PD and periodontitis combination. Disturbances of local immunity was significant in active stage of PD. Based on the obtained data and analysis of latest literature data we suppose that above mentioned changes in local immunity depended on the exhaustion of adaptive properties of patients' local immunity more pronounced in case of chronic inflammation and infection foci formation in oral cavity.     

Endothelial cell apoptosis is accelerated by inorganic iron and heat via an oxygen radical dependent mechanism

BACKGROUND: Iron participates in diverse pathologic processes by way of the Fenton reaction, which catalyzes the formation of reactive oxygen species (ROS). To test the hypothesis that this reaction accelerates apoptosis, we used human umbilical vein endothelial cells (HUVECs) as surrogates for the microvasculature in vivo. METHODS: HUVECs were loaded with Fe [III](ferric chloride and ferric ammonium citrate) with 8-hydroxyquinoline as carrier and were then challenged with two stimuli of the heat shock response, authentic heat or sodium arsenite. Iron dependence was tested with two chelators, membrane-impermeable deferoxamine and membrane-permeable o-phenanthroline. The role of ROS was assessed with superoxide dismutase, catalase, and the reporter compound dichlorofluorescein diacetate. The mechanism of cell death was assessed with three complementary techniques, Annexin V/propidium iodide labeling, the TUNEL stain, and electron microscopy. RESULTS: Iron-loaded HUVECs executed apoptosis after a heat shock stimulus. Iron-catalyzed formation of ROS appeared to be a critical mechanism, because both chelation of iron and enzymatic detoxification of ROS attenuated this apoptosis. CONCLUSIONS: Inorganic iron, in concert with chemical and physical inducers of the heat shock response, may trigger apoptosis. The accumulation of iron in injured tissue may thereby predispose to accelerated apoptosis and account, in part, for poor wound healing and organ failure.     

Evolution of boride morphologies in TiAl-B alloys

The solidification of γ-TiAl alloys with relatively low (<2 at. pct) additions of boron is discussed. Binary Ti-Al alloys containing 49 to 52 at. pct Al form primary α-(Ti) dendrites from the melt, which are subsequently surrounded by γ segregate as the system goes through the peritectic reactionL + α →γ. Alloys between 45 and 49 at. pct Al go through a double peritectic cascade, forming primary β-(Ti) surrounded by α-(Ti) and eventually by γ in the interdendritic spaces. Boron additions to these binary alloys do not change the basic solidifi-cation sequence of the matrix but introduce the refractory compound TiB₂ in a variety of mor-phologies. The boride develops as highly convoluted flakes in the leaner alloys, but needles, plates, and equiaxed particles gradually appear as the B content increases above ∼1 at. pct. Increasing the solidification rate initially promotes the formation of flakes over plates/needles and ultimately gives way to very fine equiaxed TiB₂ particles in the interdendritic spaces of the metallic matrix. Furthermore, the primary phase selection in the 49 to 52 at. pct Al range changes from α-(Ti) to β-(Ti) at supercoolings of the order of 200 K. The different boride morphologies are fully characterized, and their evolution is rationalized in terms of differences in their nucleation and growth behavior and their relationship to the solidification of the inter-metallic matrix. Formerly Research Assistant, University of California-Santa Barbara (UCSB) Formerly Professor of Materials and Dean of the College of Engineering at UCSB     

Modulation of the action of gonadotrophin surge-attenuating factor by gonadotrophin-releasing hormone

Gonadotrophin surge-attenuating factor (GnSAF) is a putative non-steroidal ovarian factor which attenuates the luteinizing hormone (LH) surge in superovulated women through the reduction of the pituitary response to gonadotrophin-releasing hormone (GnRH). The mechanism of action of GnSAF on gonadotrophin secretion was further studied by investigating six normally ovulating women in two cycles--a spontaneous and a follicle-stimulating hormone (FSH)-treated cycle. The response of the pituitary to five consecutive pulses of GnRH was investigated in late follicular phase (follicle size 15 mm) of both cycles. GnRH pulses, 10 micrograms each, were injected i.v. every 2 h and LH was measured in blood samples taken before and 30, 60 and 120 min after each pulse. FSH was injected daily at the fixed dose of 225 IU starting on cycle day 2. Peak values of LH increment occurred 30 min after each pulse. However, maximal LH increment occurred in both cycles after the second GnRH dose. In the FSH cycles the response of LH to the first three pulses was significantly attenuated compared with the spontaneous cycles, while the response to the fourth and fifth pulses was similar in the two cycles. In both cycles, LH increment 30 min post GnRH (net increase above the previous value) was similar after the fourth and fifth pulses. Serum concentrations of oestradiol and immunoreactive inhibin, although higher in the FSH cycles, remained stable throughout the GnRH experimental period in both cycles. These results demonstrate that multiple submaximal doses of GnRH can override the attenuating effect of GnSAF on LH secretion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Changes in the lymph nodes of rats under the influence of natural sorbents in damaging exposure to carbophos

The experiment was performed in male Wistar rats to study the influence of natural sorbents (Tyumen diatomites and Novosibirsk kudurites) administered with food at dose 6% of its dry weight on lymph nodes. The data obtained demonstrated that addition of natural sorbents to food does not exert pathological influence on lymph nodes of experimental animals. Sorbent diet affects follicular and paracortical lymph node structures, changing their sizes and cytological composition; natural sorbents increase immune potential which is realized after the impairing action.     

Characterization of clinical isolates of Streptococcus agalactiae by random amplified polymorphic DNA using degenerate oligonucleotides

Epidemiological studies of Streptococcus agalactiae strains have been limited by the lack of sensitive and discriminatory methods for comparing clinical isolates. Serotyping, albeit a widely used methodology, has been shown to possess low capability to distinguish between epidemiologically related and unrelated isolates. We have employed here a random amplification of polymorphic DNA (RAPD) assay, using degenerate oligonucleotides as primers, to characterize S. agalactiae isolates from related or unrelated clinical samples. Epidemiologically-related isolates (mother-infant pairs) showed identical profiles by this methodology. On the contrary, 12 epidemiologically-unrelated isolates (classified into 5 different serotypes) resulted in 11 distinct RAPD patterns. This suggests that the proposed modified RAPD assay provides a highly discriminatory tool for the analysis of genomic diversity among isolates from pathogenic organisms.     

Auditory assessment in a protocol of concurrent carboplatin and irradiation use in fractionated therapy

Possible ototoxicity related with a hyperfractionated concurrent chemo-radiation schedule was studied in 36 patients with head and neck cancer. The schedule consisted of two daily fractions, each consisting of 5 mg/m2 of carboplatin plus 115 cGy. Therapy was given 5 days a week for 7 weeks up to a total dose of 700 mg carboplatin and 8050 cGy. Tonal audiograms and superliminal tests were carried out before treatment, at conclusion, six months post-treatment, and every year thereafter. After a mean follow-up of 18 months (maximum 30 months), no treatment-related sensorineural hearing loss was observed. However, recruitment disappeared in post-treatment superliminal tests in 37% of patients who presented sensorineural deafness with recruitment, although it reappeared in audiograms recorded six months later. We attributed this to transient demyelinization. After treatment, a previous tympanosclerosis reactivated in 1 case and effusive otitis media occurred in 8 patients. Previous effusive otitis media disappeared in 1 patient (nasopharyngeal tumor).