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Biomedical subjects

A Ferrara

Publications and source records attributed to A Ferrara.

At least 37 records · Page 2Linked to original sources
PubMed2001

Effect of different antibacterial agents and surfactant protein-A (SP-A) on adherence of some respiratory pathogens to bronchial epithelial cells.

Some antibiotics at sub-inhibitory concentrations are able to alter bacterial surface structures and modulate adhesiveness by affecting the expression of microbial adhesins. An important mechanism of pulmonary defence against pathogens is SP-A, one of the proteins of the alveolar surfactant having opsonizing activity. The aim of this study was to investigate the effect that sub-inhibitory concentrations of different antibiotics and physiological concentrations of SP-A (1 and 5 microg/ml) could exert on the adherence of respiratory pathogens to the bronchial epithelial cell line, WI26VA4. Cefdinir and clarithromycin showed high efficacy, mainly at 1/2 MIC, in reducing the adherence of Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae strains to values lower or equal to 50% of the control; sparfloxacin showed the same effect on S. aureus and S. pneumoniae but teicoplanin only on S. pneumoniae. Other similar results were observed with netilmicin on Klebsiella pneumoniae (40%) and with cefepime and ciprofloxacin on Pseudomonas aeruginosa (60%). Clarithromycin reduced the adherence of K. pneumoniae to 80% although it is not active against this strain. Adherence of the test strains was not modified by SP-A alone or in combination with any of the antibiotics used.

Anti-Bacterial Agents↗
PubMed2001

Effect of some fractions of alveolar surfactant (phospholipids and SP-A) on the bactericidal activity of different antimicrobials against some respiratory pathogens.

OBJECTIVES: To investigate the effects of physiologic concentrations, at alveolar level, of some fractions of pulmonary surfactant (phospholipids and SP-A) on the bactericidal activity of different antimicrobials against some respiratory pathogens. METHODS: The antimicrobial agents cefdinir, sparfloxacin, clarithromycin, teicoplanin, cefepime, ciprofloxacin, netilmicin and tobramycin, depending on their specific activity, were investigated against Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae and Pseudomonas aeruginosa. Killing curves were carried out with antimicrobials at 0.5 and 2 MIC, SP-A at 1 and 5 mg/L and phospholipids at 50 mg/L. RESULTS: Time-kill experiments showed that while SP-A never modified the activity of antimicrobials, phospholipids exerted, in some cases, a weak antagonistic effect. Among antibacterials and pathogens investigated, phospholipids were able to decrease the rate of killing of cefepime and ciprofloxacin only on P. aeruginosa, both at 0.5 and at 2 MIC, with an increase of about 1 log in CFU. The combination of SP-A and phospholipids never modified the effect observed in the presence of lipids alone. CONCLUSIONS: The paucity of data only allow us to observe that the examined antibiotics do not have substantially reduced activity against respiratory pathogens studied in the presence of physiologic concentrations of some fractions of surfactant. Cefepime alone already exerted a small effect, and ciprofloxacin at 2 MIC, even in the presence of phospholipids, retained its bactericidal activity.

Anti-Bacterial Agents↗
PubMed2001

Hormone replacement therapy is associated with better glycemic control in women with type 2 diabetes: The Northern California Kaiser Permanente Diabetes Registry.

OBJECTIVE: In women with diabetes, the changes that accompany menopause may further diminish glycemic control. Little is known about how hormone replacement therapy (HRT) affects glucose metabolism in diabetes. The aim of this study was to examine whether HbA(1c) levels varied by current HRT among women with type 2 diabetes. RESEARCH DESIGN AND METHODS: In a cohort of 15,435 women with type 2 diabetes who were members of a health maintenance organization, HbA(1c) and HRT were assessed by reviewing records in the health plan's computerized laboratory and pharmacy systems. Sociodemographic and clinical information were collected by survey. RESULTS: The mean age was 64.7 years (SD +/- 8.7). The study cohort comprised 55% non-Hispanic whites, 14% non-Hispanic blacks, 12% Hispanics, 11% Asians, 4% "other" ethnic groups, and 4% with missing ethnicity data. Current HRT was observed in 25% of women. HbA(1c) levels were significantly lower in women currently using HRT than in women not using HRT (age-adjusted mean +/- SE: 7.9 +/- 0.03 vs. 8.5 +/- 0.02, respectively, P = 0.0001). No differences in HbA(1c) level were observed between women using unopposed estrogens and women using opposed estrogens. In a Generalized Estimating Equation model, which took into account patient clustering within physician and adjusted for age, ethnicity, education, obesity, hypoglycemic therapy, diabetes duration, self-monitoring of blood glucose, and exercise, HRT remained significantly and independently associated with decreased HbA(1c) levels (P = 0.0001). CONCLUSIONS: HRT was independently associated with decreased HbA(1c) level. Clinical trials will be necessary to understand whether HRT may improve glycemic control in women with diabetes.

Aged↗
PubMed2001

Developing a prediction rule from automated clinical databases to identify high-risk patients in a large population with diabetes.

OBJECTIVE: To develop and validate a prediction rule for identifying diabetic patients at high short-term risk of complications using automated data in a large managed care organization. RESEARCH DESIGN AND METHODS: Retrospective cohort analyses were performed in 57,722 diabetic members of Kaiser Permanente, Northern California, aged > or =19 years. Data from 1994 to 1995 were used to model risk for macro- and microvascular complications (n = 3,977), infectious complications (n = 1,580), and metabolic complications (n = 316) during 1996. Candidate predictors (n = 36) included prior inpatient and outpatient diagnoses, laboratory records, pharmacy records, utilization records, and survey data. Using split-sample validation, the risk scores derived from logistic regression models in half of the population were evaluated in the second half. Sensitivity, positive predictive value, and receiver operating characteristics curves were used to compare scores obtained from full models to those derived using simpler approaches. RESULTS: History of prior complications or related outpatient diagnoses were the strongest predictors in each complications set. For patients without previous events, treatment with insulin alone, serum creatinine > or =1.3 mg/dl, use of two or more antihypertensive medications, HbA(1c) >10%, and albuminuria/microalbuminuria were independent predictors of two or all three complications. Several risk scores derived from multivariate models were more efficient than simply targeting patients with elevated HbA(1c) levels for identifying high-risk patients. CONCLUSIONS: Simple prediction rules based on automated clinical data are useful in planning care management for populations with diabetes.

Adult↗
PubMed2001

[Ectopic thyroid: report of a case].

The development of thyroid tissue can occur in any moment of the migration of the thyroid along the thyroglossal duct from the tongue, resulting in lingual (at tongue base), sublingual (below the tongue), prelaryngeal (in front of the larynx), and substernal (in the mediastinum) ectopy. Thyroglossal duct cyst is the most common type of clinical abnormality related to thyroid ectopy. Surgical removal of such ectopic tissue is justified since some Authors describe thyroid cancer arising from aberrant thyroid tissue. The Authors report a case of thyroid ectopy in a patient who underwent 20 years before a left thyroid resection with isthmectomy; during the operation the surgeon described a hypertrophic pyramidal lobe which was left in situ and the patients did not receive any hormone suppressing therapy.

Choristoma↗
PubMed2000

Hemodynamic and pulmonary changes during open, carbon dioxide pneumoperitoneum and abdominal wall-lifting cholecystectomy. A prospective, randomized study.

BACKGROUND: Carbon dioxide (CO2) pneumoperitoneum effects are still controversial. The aim of this study was to investigate cardiopulmonary changes in patients subjected to different surgical procedures for cholecystectomy. METHODS: In this study, 15 patients were assigned randomly to three groups according to the surgical procedure to be used: open cholecystectomy (OC), CO2 pneumoperitoneum cholecystectomy (PP), and laparoscopic gasless cholecystectomy (abdominal wall lifting [AWL]), respectively. A pulmonary artery catheter was used for hemodynamic monitoring in all patients. A subcutaneous multiplanar device (Laparo Tenser) was used for abdominal wall lifting. To avoid misinterpretation of results, conventional anesthesia was performed with all parameters, and the position of the patients held fixed throughout surgery. The following parameters were analyzed: mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume index (SVI), central venous pressure (CVP), systemic vascular resistances index (SVRI), mean pulmonary arterial pressure (MPAP), pulmonary capillary wedge pressure (PCWP), pulmonary vascular resistances index (PVRI), peak inspiratory pressure (PIP), end-tidal CO2 pressure (ETCO)2, CO2 arterial pressure (PaCO2), and arterial pH. RESULTS: All the operations were completed successfully. The Laparo Tenser allowed good exposition of the surgical field. A slight impairment of the cardiopulmonary functions, with reduction of SVRI, MAP, and CI and elevation of pulmonary pressures and vascular resistance, followed induction of anesthesia. However, these effects tended to normalize in the OC and AWL groups over time. In contrast, CO2 insufflation produced a complex hemodynamic and pulmonary syndrome resulting in increased right- and left side filling pressures, significant cardiac index reduction, derangement of the respiratory mechanics, and respiratory acidosis. All of these effects normalized after desufflation. CONCLUSIONS: Cardiopulmonary adverse effects of general anesthesia were significant but transitory and normalized during surgery. Carbon dioxide pneumoperitoneum caused a significant impairment in cardiopulmonary functions. In high-risk patients, gasless laparoscopy may be preferred for reliability and absence of cardiopulmonary alterations.

Abdominal Muscles↗
PubMed2000

Temporal differentiation in two strains of small rodents: a wood mouse (Apodemus sylvaticus) and an albino mouse (Mus musculus OF1).

Wood mice (Apodemus sylvaticus) and OF1 albino mice (Mus musculus) were compared over durations ranging from 0.5 to 7 s, using the differential reinforcement of response duration schedule (DRRD) and a 'platform' response, i.e. staying on a small platform for a specified criterion duration to be reinforced. Species-related differences were found for mean response durations, efficiency and the number of trials needed to reach a preset performance criterion. Coefficients of variation of response durations did not differ. Overall, OF1 mice needed more trials than wood mice to reach a temporal criterion. However, over 3-7 s, data from both strains almost fitted the behavioral assumptions of Scalar Timing theory. Performance of mongolian gerbils (Meriones unguiculatus) trained in a similar setting was shown for visual comparison.

Journal Article↗
PubMed2000

The Influence of Galactic Outflows on the Formation of Nearby Dwarf Galaxies.

We show that the gas in growing density perturbations is vulnerable to the influence of winds outflowing from nearby collapsed galaxies that have already formed stars. This suggests that the formation of nearby galaxies with masses less, similar10(9) M( middle dot in circle) is likely to be suppressed, irrespective of the details of galaxy formation. An impinging wind may shock-heat the gas of a nearby perturbation to above the virial temperature, thereby mechanically evaporating the gas, or the baryons may be stripped from the perturbation entirely if they are accelerated to above the escape velocity. We show that baryonic stripping is the most effective of these two processes, because shock-heated clouds that are too large to be stripped are able to radiatively cool within a sound crossing time, limiting evaporation. The intergalactic medium temperatures and star formation rates required for outflows to have a significant influence on the formation of low-mass galaxies are consistent with current observations, but may soon be examined directly via associated distortions in the cosmic microwave background and with near-infrared observations from the Next Generation Space Telescope, which may detect the supernovae from early-forming stars.

Journal Article↗
PubMed2000

Prevalence and risk factors of Helicobacter pylori-negative peptic ulcer: a multicenter study.

Peptic ulcer disease (PUD) has been described in the absence of Helicobacter pylori (Hp) infection, suggesting that different factors are involved in its etiopathogenesis. We investigated prevalence and characteristics of Hp-negative (Hp-) PUD in an area of Northern Italy and calculated the rate of Hp-positive (Hp+) patients with PUD in whom Hp might be coincidental and not causal. Four hundred nine consecutive patients with endoscopically diagnosed PUD were enrolled in seven hospitals. Hp infection was assessed by rapid urease test and histologic examination. The attributable risk percentages in different age groups were calculated by appropriate formulas. Of 409 patients, 31 (7.6%) were Hp- (gastric, 8.3%; duodenal, 7.6%). Age, nonsteroidal antiinflammatory drug (NSAID) consumption, and complication rates were significantly higher in Hp-than Hp+ patients with duodenal ulcers (DUs). Of the Hp-patients with DU, 58% did not use NSAIDs. In patients with Hp+ DU, the attributable risk percentage for Hp infection in patients aged <40 years, 40-60 years, or >60 years was 98%, 88%, and 66%, respectively. The prevalence of Hp- PUD was about 8%, mainly unrelated to any known etiologic factor. In about one-third of Hp+ patients with PUD aged over 60 years, Hp infection might be coincidental and not causal.

Adult↗
PubMed2000

Segmental colitis associated with diverticula: a prospective study. Gruppo di Studio per le Malattie Infiammatorie Intestinali (GSMII).

OBJECTIVE: Little is known about the clinical features and natural history of segmental colitis associated with diverticula. Our aim was to evaluate the incidence of segmental colitis associated with diverticula in patients undergoing colonoscopy, its clinical picture, and its outcome. METHODS: This was a multicenter, prospective study. Patients with inflammatory bowel disease (IBD)-like lesions limited to colonic segments with diverticula were enrolled. Patients were treated with oral and topical 5-aminosalicylic (5-ASA) until remission was achieved; clinical and endoscopic follow-up was planned at 6 wk and 12 months. RESULTS: A total of 5457 consecutive colonoscopies were recorded at five participating institutions; 20 patients (0.36%) met the endoscopic criteria for segmental colitis associated with diverticula. All had lesions in the left colon, and one also had lesions in the right colon. In six cases, a specific diagnosis was made thereafter. The remaining 14 patients (0.25% of colonoscopies; eight men; age range, 49-80 yr) were in clinical and endoscopic remission at the first follow-up visit. At onset, 13/14 had hematochezia, seven had diarrhea, and five had abdominal pain; only one had weight loss. No subject had fever. In all but one case, blood chemistries were normal. Five patients had had similar symptoms previously. Thirteen of 14 patients were in clinical and endoscopic remission at 12 months. CONCLUSIONS: This endoscopic picture is not an exceptional finding. Hematochezia was the main clinical feature, and no relation with gender, age, or smoking habit was found. Blood chemistries were generally normal and the rectum was spared. The histological features were not diagnostic and most patients did not complain of any abdominal symptoms 12 months after enrollment.

Aged↗
PubMed2000

Self-monitoring of blood glucose: language and financial barriers in a managed care population with diabetes.

OBJECTIVE: Self-monitoring of blood glucose (SMBG) is a cornerstone of diabetes care, but little is known about barriers to this self-care practice. RESEARCH DESIGN AND METHODS: This cross-sectional study examines SMBG practice patterns and barriers in 44,181 adults with pharmacologically treated diabetes from the Kaiser Permanente Northern California Region who responded to a health survey (83% response rate). The primary outcome is self-reported frequency of SMBG. RESULTS: Although most patients reported some level of SMBG monitoring, 60% of those with type 1 diabetes and 67% of those with type 2 diabetes reported practicing SMBG less frequently than recommended by the American Diabetes Association (three to four times daily for type 1 diabetes, and once daily for type 2 diabetes treated pharmacologically). Significant independent predictors of nonadherent practice of SMBG included longer time since diagnosis, less intensive therapy, male sex, age, belonging to an ethnic minority, having a lower education and neighborhood income, difficulty communicating in English, higher out-of-pocket costs for glucometer strips (especially for subjects with lower incomes), smoking, and excessive alcohol consumption. CONCLUSIONS: Considerable gaps persist between actual and recommended SMBG practices in this large managed care organization. A somewhat reduced SMBG frequency in subjects with linguistic barriers, some ethnic minorities, and subjects with lower education levels suggests the potential for targeted, culturally sensitive, multilingual health education. The somewhat lower frequency of SMBG among subjects paying higher out-of-pocket expenditures for strips suggests that removal of financial barriers by providing more comprehensive coverage for these costs may enhance adherence to recommendations for SMBG.

Adult↗
PubMed1999

Do elderly women have more physical disability than men do?

This study investigated whether the commonly observed higher prevalence of physical disability among women is due to higher incidence rates or to other factors such as selective mortality or poor recovery. Methods included observed measures of prevalent lower body physical disability and potential risk factors at baseline (1989-1991) and 4-year follow-up of 2,025 community-dwelling adults aged 55 years and older in Marin County, California. Incidence, recovery, and mortality rates were determined at the follow-up examination. Results indicated that women had higher age-specific and age-adjusted prevalence rates at both examinations (odds ratios = 1.66 and 1.60, p<0.001) but that incidence rates were not significantly different (odds ratio = 1.12, 95% confidence interval: 0.77, 1.64). In the classic formulation, prevalence = incidence x duration, the higher prevalence rates in women could not be due to a higher incidence rate, but could be explained by longer duration due to lower recovery and mortality rates in women. Incident physical disability was predicted by prevalent chronic illnesses, poor vision, obesity, physical inactivity, poor memory, fewer social activities, and higher depression scores, but not by sex. Prevention efforts should concentrate on reducing known risk factors in both men and women and on promoting higher recovery rates among women.

Aged↗
PubMed1999

Small-cell carcinoma of the rectum: report of two cases.

Small-cell carcinoma of the rectum is an infrequent pathologic finding, and its precise incidence is unknown. Its incidence is less than 0.2 percent among all colorectal cancers. This tumor manifests highly aggressive behavior. The treatment of choice is combination chemotherapy similar to that used for small-cell carcinoma of the lung, but in small localized tumors surgery plus chemotherapy is an alternative. We present two cases of small-cell carcinoma of the lower rectum and a review of the literature.

Aged↗
PubMed1999

Excess maternal transmission of type 2 diabetes. The Northern California Kaiser Permanente Diabetes Registry.

OBJECTIVE: To assess excess maternal transmission of type 2 diabetes in a multiethnic cohort. Previous studies have reported higher prevalence of diabetes among mothers of probands with type 2 diabetes than among fathers. This analysis is vulnerable to biases, and this pattern has not been observed in all populations or races. RESEARCH DESIGN AND METHODS: We assessed evidence for excess maternal transmission among 42,533 survey respondents with type 2 diabetes (probands) by calculating the prevalence of diabetes in their siblings and offspring. To assess data quality, we evaluated completeness of family history data provided. Accuracy of family information reported by probands was also evaluated by comparing survey responses in a subsample of 206 probands with family histories modified after further interviews with relatives. RESULTS: Siblings (n = 60,532) of probands with affected mothers had a greater prevalence of diabetes (20%) than those with affected fathers (17%) (P < 0.001 for adjusted odds ratios). Prevalence of diabetes was higher among the offspring (n = 72,087) of female (3.4%) versus male (2.2%) probands (P < 0.001 for adjusted odds ratios). These patterns were evident in all races and both sexes; however, the effect size was clinically insignificant in African-Americans and male offspring. In general, probands provided more complete data about diabetes status for the maternal arm of the pedigree than the paternal arm. Completeness of knowledge was not related to proband sex, but was related to education and race, and inversely to age. Accuracy of proband-reported family history was consistently good (kappa statistics generally > 0.70). CONCLUSIONS: Excess maternal transmission was observed in all races and both sexes, although the size of the excess was negligible in African-Americans and male offspring. Potential reporting and censoring biases are discussed.

Adolescent↗
PubMed1998

Peak procedure performance in young adult and aged rats: acquisition and adaptation to a changing temporal criterion.

Twenty-four-month-old and 4-month-old rats were trained on a peak-interval procedure, where the time of reinforcement was varied twice between 20 and 40 sec. Peak times from the old rats were consistently longer than the reinforcement time, whereas those from younger animals tracked the 20- and 40-sec durations more closely. Different measures of performance suggested that the old rats were either (1) systematically misremembering the time of reinforcement or (2) using an internal clock with a substantially greater latency to start and stop timing than the younger animals. Old rats also adjusted more slowly to the first transition from 20 to 40 sec than did the younger ones, but not to later transitions. Correlations between measures derived from within-trial patterns of responding conformed in general to detailed predictions derived from scalar expectancy theory. However, some correlation values more closely resembled those derived from a study of peak-interval performance in humans and a theoretical model developed by Cheng and Westwood (1993), than those obtained in previous work with animals, for reasons that are at present unclear.

Adaptation, Psychological↗