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1.
Chem Commun (Camb) ; 53(54): 7624-7627, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28640293

RESUMO

Traditional methods for deriving computationally-generated collision cross sections for comparisons with ion mobility-mass spectrometry data require 3-dimensional energy-minimized structures and are often time consuming, preventing high throughput implementation. Here, we introduce a method to predict ion mobility collision cross sections of lipids and peptide analogs important in prebiotic chemistry and other fields. Using less than 100 2-D molecular descriptors this approach resulted in prediction errors of less than 2%.

2.
Science ; 196(4294): 1084-5, 1977 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-17778540
3.
J Hosp Infect ; 23(3): 167-74, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8099091

RESUMO

Infection control is an important issue in the dental surgery but the potential hazards associated with contaminated dental water have received relatively little attention in recent years. The complex design of the equipment results in stagnation of water within the dental chair and subsequent amplification of contaminating environmental organisms, including pseudomonads and legionellae, to potentially hazardous levels. Immunocompromised patients may be at particular risk of infection. Very poor water quality with total bacterial counts above 10(4) ml-1 is unpleasant for all patients, and the dental chair supply should be of drinking water quality. In addition to these problems, bacteria and viruses may be aspirated from the oral cavity and contaminate the handpiece. Measures to reduce microbial contamination of dental chairs and equipment include flushing water through the chair's equipment at the beginning of each day; continuous or pulsed water chlorination, or application of biocides other than chlorine; provision of sterile bottled water in the system; and autoclaving handpieces between patients. Future dental chair design must attempt to resolve the problems associated with microbial contamination of the water supply and aerosols generated during dental procedures.


Assuntos
Equipamentos Odontológicos , Contaminação de Equipamentos , Microbiologia da Água , Infecções Bacterianas/transmissão , Humanos , Hospedeiro Imunocomprometido , Controle de Infecções/métodos , Controle de Qualidade , Fatores de Risco
4.
J Hosp Infect ; 16(1): 9-18, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1974912

RESUMO

The apparent failure of hyperchlorination and continuous dosing with chlorine to eliminate legionellae from a dental teaching hospital water supply prompted a prospective study to evaluate charcoal filters as a means of decontamination. Legionella pneumophila serogroup 10 and L. bozemanii serogroup 2 were isolated from dental units yielding 10(1)-10(3) colony forming units (cfu) ml-1 with total bacterial counts in the range 10(2)-greater than 10(4) cfu ml-1. After chair-side installation of charcoal filters bacterial contamination of the dental unit water was prevented and legionellae were initially not detected, but after 7 days the total count returned to pre-filtration levels of greater than 10(4) cfu ml-1; L. pneumophila serogroup 10 was eliminated but L. bozemanii serogroup 2 persisted. These results suggest that neither chlorination nor charcoal filtration deal adequately with the potential hazard of Legionella spp. in dental water.


Assuntos
Cloro , Equipamentos Odontológicos , Desinfecção/métodos , Legionella/isolamento & purificação , Esterilização/métodos , Abastecimento de Água , Carvão Vegetal , Filtração , Legionella/efeitos dos fármacos , Estudos Prospectivos
5.
J Hosp Infect ; 27(3): 195-9, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7963460

RESUMO

A review of all blood culture isolates for the 16 years from 1976 were collated with prospective laboratory and clinical records of 620 sickle cell patients treated at King's College Hospital. Over half of all salmonella bacteraemias diagnosed in the clinical laboratory occurred in sickle cell disease (SCD) patients. Of 21 bacteraemias in SCD patients, 11 (52.3%) were due to Salmonella spp. compared with 23 (0.4%) of 4884 bacteraemias in patients without SCD (P = < 0.00001). In SCD, Gram-negative bacilli were responsible for 16 (76.2%) bacteraemias, of which 11 (68.8%) were due to Salmonella spp. but there were no cases of S. typhi or S. paratyphi. An increase in the number of salmonella infections over the past 5 years were noted in the SCD and non-SCD patients, nine and 16 cases respectively, compared with two and seven cases in the previous decade. However, the recent increase of S. enteritidis phage type 4 in the UK was not evident in SCD patients. These findings have important preventative and therapeutic implications for the management of SCD patients.


Assuntos
Anemia Falciforme/complicações , Bacteriemia/complicações , Infecções por Salmonella/complicações , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Hospitais Universitários , Humanos , Londres/epidemiologia , Estudos Prospectivos , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Fatores de Tempo
6.
J Infect ; 20(1): 11-9, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2405057

RESUMO

Nocardiosis arose in seven of 191 liver transplant patients (3.7%) over a period of 3.5 years. Four patients had only pulmonary lesions while three had disseminated disease. Nocardia asteroides was isolated from three patients following bronchoscopy, percutaneous aspirate of a pulmonary lesion in one patients, and from the skin from the aspirates in three patients. Delay in diagnosis in two cases was due to negative microscopy; in one, the diagnosis was made only after repeated bronchoscopy. Of the seven patients, three (43%) died. In two of these, nocardiosis was considered to have directly contributed to death. Co-existent bacterial and viral infections were present in all patients who died. In vitro susceptibility of the organism to co-trimoxazole was variable and did not necessarily reflect clinical efficacy. In one patient, a good clinical response was achieved with co-trimoxazole despite apparently reduced in vitro susceptibility.


Assuntos
Transplante de Fígado , Nocardiose/diagnóstico , Sulfadiazina/uso terapêutico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto , Resistência Microbiana a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nocardiose/tratamento farmacológico , Nocardiose/etiologia , Nocardia asteroides/isolamento & purificação
8.
J Exp Biol ; 135: 65-76, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3373145

RESUMO

Transport mechanisms for NaCl in intestinal brush border membrane vesicles (BBMV) of herbivorous, seawater-adapted tilapia, Oreochromis mossambicus, were investigated with a rapid filtration technique using 22Na+ and 36Cl- as tracers. Evidence to support the existence of cotransport mechanisms (Na+/Cl- or Na+/K+/2Cl-) in tilapia intestinal BBMV was not found. An inwardly directed Cl- gradient or KCl gradient did not stimulate the uptake of Na+ into tilapia intestinal BBMV. Furthermore, the uptake of Na+ under these conditions was not significantly affected by furosemide. Evidence was found to indicate the existence of Na+/H+ and Cl-/HCO3- antiport mechanisms for NaCl transport in tilapia intestinal BBMV. An outwardly directed proton gradient (pH 6.0 in, pH 7.5 out) stimulated the uptake of Na+ above that of the control (pH 7.5 in, pH 7.5 out). Exogenous amiloride (1 mmol l-1) significantly reduced Na+ uptake in the presence of an outwardly directed proton gradient. Apparent influxes of 1 mmol l-1 Na+ were (nmol mg protein -1 15 s-1 +/- 1 S.E.): control, 1.46 +/- 0.09; pH gradient, 3.36 +/- 0.14; pH gradient plus amiloride, 1.55 +/- 0.05. The uptake of Cl- was stimulated by outwardly directed HCO3- and Cl- gradients in comparison with an outwardly directed gluconate gradient. Apparent influxes of 10 mmol l-1 Cl- were (nmol mg protein-1 15 s-1 +/- 1 S.E.): gluconate, 12.90 +/- 0.19; HCO3-, 15.83 +/- 0.34; Cl-, 14.62 +/- 0.42. These results suggest that, in contrast to the cotransport mechanisms for NaCl that have been reported for other fish intestine, the herbivorous marine teleost, Oreochromis mossambicus, possesses dual antiport mechanisms for the transport of NaCl across its intestinal brush border membrane.


Assuntos
Proteínas de Transporte/metabolismo , Cloretos/metabolismo , Peixes/metabolismo , Mucosa Intestinal/metabolismo , Microvilosidades/metabolismo , Sódio/metabolismo , Simportadores , Amilorida/farmacologia , Animais , Dieta , Furosemida/farmacologia , Cinética , Microvilosidades/efeitos dos fármacos , Plantas , Simportadores de Cloreto de Sódio
9.
Appl Opt ; 14(12): 2827-30, 1975 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20155118

RESUMO

This brief sketch of the contributions of the fourth Baron Rayleigh is intended to supplement the biographical material contained in the October 1964 issue of Applied Optics.

10.
J Antimicrob Chemother ; 31(6): 973-84, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8360134

RESUMO

An open, randomized study was performed at 18 European centres to compare the efficacy, safety and tolerance of oral fluconazole with oral polyenes for the prophylaxis of fungal colonization and infection in adults at high risk of developing neutropenia. Five hundred and thirty-six hospitalized patients with malignant disease, about to receive chemotherapy, radiotherapy, or bone marrow transplantation, and who were already neutropenic or were expected to develop neutropenia were included in the study. Before therapy or transplantation, patients commenced either oral fluconazole therapy (50 mg/day as a single dose) or oral polyenes therapy (amphotericin B 2 g/day and/or nystatin 4 x 10(6) units/day in four or more divided doses), for a mean of 29.3 days and 31.3 days, respectively. After baseline clinical and mycological testing, patients were re-evaluated at least weekly during prophylaxis, at the end of prophylaxis and two to six weeks later to identify proven or suspected fungal infection and to determine rates of colonization with fungi. Fungal infection was diagnosed in 41 of 511 evaluable patients, 10 (3.9%) of 256 in the fluconazole group and 31 (12.2%) of 255 in the polyene group (P = 0.001). This total included four patients (1.6%) in the fluconazole group who developed oropharyngeal candidiasis compared with 22 (8.6%) in the polyene group (P < 0.001). Systemic infections comprised 6 (2.3%) in the fluconazole group and 9 (3.5%) in the polyene group (P = not significant), and included three Candida krusei infections in each group. Parenteral amphotericin B therapy was given empirically for persistent fevers in an additional 62 (24.2%) patients receiving fluconazole and 59 (23.1%) receiving polyenes (P = not significant). Colonization with fungi was generally similar in each treatment group, although an increased proportion of patients receiving fluconazole developed colonization of the faeces (P < 0.01). Adverse reactions, possibly related to treatment, were recorded in 15 (5.6%) of 269 patients in the fluconazole group and 14 (5.2%) of 267 in the polyene group; these necessitated discontinuation of therapy in seven patients in each group. Once-a-day fluconazole was therefore more effective than oral polyenes for the prevention of oropharyngeal fungal infection and as effective for the prevention of infections at other sites in patients with neutropenia.


Assuntos
Anfotericina B/uso terapêutico , Fluconazol/uso terapêutico , Micoses/prevenção & controle , Neutropenia/complicações , Nistatina/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anfotericina B/administração & dosagem , Anfotericina B/efeitos adversos , Criança , Feminino , Fluconazol/administração & dosagem , Fluconazol/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Nistatina/administração & dosagem , Nistatina/efeitos adversos
11.
J Antimicrob Chemother ; 26 Suppl F: 89-99, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2292549

RESUMO

In a randomized multicentre study ciprofloxacin combined with azlocillin was compared with gentamicin and azlocillin for the treatment of febrile episodes in neutropenic patients. In 147 evaluable episodes in 108 patients, 80 patients received ciprofloxacin/azlocillin and 67 received gentamicin/azlocillin. The two treatment groups were comparable in terms of age, underlying diagnosis, and duration of neutropenia. Microbiologically documented infections were the cause of fever in 34 (42.5%) and 29 (43.3%) episodes in the ciprofloxacin/azlocillin and gentamicin/azlocillin groups respectively. At the end of therapy, 46 patients (57.5%) receiving ciprofloxacin/azlocillin showed complete resolution compared with 30 (44.7%) for the gentamicin/azlocillin group (P = 0.14). The clinical response rate for microbiologically documented episodes was 58.8% and 48.3% respectively (P = 0.45). Among the microbiologically documented infections with follow-up cultures available, 24 (92.3%) of 26 isolates from patients receiving ciprofloxacin/azlocillin were eradicated, in comparison with 19 (86.4%) of 22 in the gentamicin/azlocillin group (P = 0.65). There were five superinfections, all in the gentamicin/azlocillin group. Significant resistance to the study drugs was not seen. Of all evaluable patients, including those subsequently withdrawn because of early modification of therapy, there were 12 deaths within the study period; six (6.8%) of these occurred in 88 patients randomized to the ciprofloxacin/azlocillin group, compared with two of 80 (2.5%) in the gentamicin/azlocillin group. Both treatments were generally well-tolerated; one patient in the ciprofloxacin/azlocillin group developed convulsions, probably related to ciprofloxacin. The combination of ciprofloxacin and azlocillin is as effective as gentamicin plus azlocillin and offers a useful alternative for the empirical treatment of febrile neutropenic patients.


Assuntos
Azlocilina/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Ciprofloxacina/uso terapêutico , Gentamicinas/uso terapêutico , Neutropenia/complicações , Adolescente , Adulto , Azlocilina/efeitos adversos , Ciprofloxacina/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/uso terapêutico , Feminino , Febre/tratamento farmacológico , Febre/etiologia , Gentamicinas/efeitos adversos , Humanos , Indução de Remissão , Superinfecção/tratamento farmacológico
12.
Appl Opt ; 26(5): 753, 1987 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20454212
13.
Appl Opt ; 26(12): 2283, 1987 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20489858
14.
Appl Opt ; 7(1): 59-60, 1968 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20062406
15.
Appl Opt ; 7(2): 323-4, 1968 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20062465
16.
Appl Opt ; 7(4): 693-4, 1968 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20068661
17.
Appl Opt ; 7(6): 1059, 1968 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20068740
18.
Appl Opt ; 7(12): 2449-50, 1968 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20069031
19.
Appl Opt ; 6(1): 106, 1967 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20057702
20.
Appl Opt ; 6(2): 219, 1967 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20057730
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