Search PubMed⌕ Search

Biomedical subjects

M Sierra

Publications and source records attributed to M Sierra.

At least 73 records · Page 4Linked to original sources

[Gastric ulcer as a unique and symptomatic manifestation of infection by cytomegalovirus in a healthy adult].

A previously healthy female without risk factors had cytomegalic inclusion disease with symptomatic gastric involvement and without evidence of systemic cytomegalovirus (CMV) infection. Multiple ulcerations with a fibrinous bottom were discovered by fibrogastroscopy in the gastric body and antrum. Histological study showed cells with intranuclear inclusions and basophilic nuclear cytoplasm. The detection of specific IgM and its subsequent negativization suggest an active CMV infection. Gastric infection may be the isolated and symptomatic feature of the disease in the healthy adult.

Aged↗

Ceftriaxone treatment of penicillinase-producing Neisseria gonorrhoeae infections in children.

The incidence of penicillinase-producing Neisseria gonorrhoeae (PPNG) among adults with gonorrhea in Brooklyn now exceeds 24%. Because children usually acquire their infection from adults, it follows that we have had a concomitant rise in PPNG among sexually abused children. The Centers for Disease Control now recommends ceftriaxone for the first line treatment of gonorrhea but there are no data as to its use in children for this indication. From May, 1987, through March, 1989, 33 children, 4 days to 10 years of age, were admitted to Kings County Hospital for 34 episodes of gonorrhea. Nine (26.5%) were caused by PPNG. Twenty-three were female; 10 were male. There were 17 isolates from the vagina, 3 from the urethra, 9 from the pharynx, 9 from the rectum and 6 from the eye. Eight children (all girls) had infections at greater than or equal to 1 site; 2 were infected at 3 sites. Twenty-eight children were sexually abused and 5 were neonates with ophthalmia (1 PPNG). All isolates were susceptible to ceftriaxone by disc diffusion testing. Agar dilution was performed for 18 isolates; minimal inhibitory concentrations to ceftriaxone were less than or equal to 0.06 mg/liter. The 5 PPNG isolates tested had minimal inhibitory concentrations to penicillin of 2 to 16 mg/liter and 3 isolates were resistant to tetracycline with minimal inhibitory concentrations of 32 mg/liter. Twenty-eight children were treated with a single dose of ceftriaxone, including the 5 neonates with ophthalmia; the dose was 125 mg if less than 45 kg or 250 mg if greater than 45 kg.(ABSTRACT TRUNCATED AT 250 WORDS)

Ceftriaxone↗

Frequency of Mycobacterium tuberculosis bacteremia in patients with tuberculosis in an area endemic for AIDS.

Mycobacterium tuberculosis bacteremia has recently been reported in patients infected with the human immunodeficiency virus (HIV). At our institution, tuberculosis occurs commonly among patients with and without HIV infection. We sought to determine the frequency of M. tuberculosis bacteremia among patients with newly diagnosed tuberculosis. During a 4-month period, mycobacterial blood cultures were obtained on all identifiable patients with newly diagnosed tuberculosis. Fifteen percent (9/59) of consecutive patients with tuberculosis had positive blood cultures for M. tuberculosis. Twenty-six percent (7/27) of patients known to be infected with HIV had positive mycobacterial blood cultures; two intravenous drug users who refused HIV-serologic testing also had positive mycobacterial blood cultures. M. tuberculosis bacteremia occurred at a higher rate among HIV-infected patients with an AIDS-defining opportunistic infection in addition to tuberculosis (3/3) than among HIV-infected patients without such an opportunistic infection (4/24; p less than 0.02). M. tuberculosis bacteremia occurred in 83% (5/6) of patients with disseminated tuberculosis and in 8% (4/53) of patients without disseminated tuberculosis (p less than 0.001). In all cases, tuberculosis was diagnosed in patients with M. tuberculosis bacteremia or else they died prior to the blood cultures demonstrating mycobacterial growth (mean time to detection of mycobacterial growth: 43 days). However, the frequent occurrence of M. tuberculosis bacteremia in HIV-infected patients with disseminated tuberculosis suggests that mycobacterial blood cultures may help confirm the diagnosis of tuberculosis in this group of patients.

Acquired Immunodeficiency Syndrome↗

Microsomal enzyme induction by permethrin in rats.

The synthetic pyrethroid, permethrin, was evaluated for its ability to alter hepatic microsomal drug-metabolizing function. The influence of permethrin (25:75 cis-trans) on plasma antipyrine kinetics and gamma-glutamyl transpeptidase (gamma-GTP) activity were studied in rats. After 3 days of administration of 90 mg permethrin/kg/day, there was no significant change in the antipyrine half-life and the area under the curve, while the apparent volume of distribution and clearance were significantly increased. Treatment with 190 mg permethrin/kg/day for 3 days decreased antipyrine half-life and the area under the curve, and increased the apparent volume of distribution and the clearance significantly. The gamma-GTP activity was significantly increased within 21 days and 14 days after the start of permethrin administration, at doses of 90 and 190 mg permethrin/kg/day, respectively. The antipyrine kinetics results indicate that permethrin is capable of producing a dose-dependent marked enzyme-inducing effect.

Animals↗

Plasma protein binding of an N-pyrrolyl derivative penicillin in several mammalian species.

The extents of protein binding of an N-pyrrolyl derivative penicillin in plasma of different species were determined in vitro by the equilibrium dialysis technique and spectrophotometry determination. The percentage of binding was determined in cows, sheep, pigs and dogs. The percentage of drug that was protein bound was independent of drug concentration for this penicillin within the range studied (5 to 40 micrograms ml-1). The extent of binding was determined at 20 micrograms ml-1. There was a significant difference in the extent of penicillin binding between species (t test P less than 0.005) except for between cows and dogs (t test P less than 0.05) and sheep and pigs (where it was not significantly different). In the species studied the extent of penicillin binding ranged from 41 to 55 per cent.

Animals↗

Comparison of HEp-2 cell culture and Abbott respiratory syncytial virus enzyme immunoassay.

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection in children. Rapid identification of RSV infections would allow for specific chemotherapy. We evaluated a means of rapid diagnosis, the Abbott enzyme immunoassay (EIA), by using 314 stored nasopharyngeal aspirates. RSV antigens were identified in 62 of 66 RSV culture-positive specimens. An additional 37 specimens from which RSV was not isolated were positive in the EIA. Of these, 29 were confirmed as truly positive by a blocking assay, for a total of 95 (66 + 29) positive specimens. The sensitivity of the EIA for total positive samples was 96% (91/95) versus 69% (66/95) for cell culture. The specificity of the EIA was 96% (211/219). In these stored specimens, Abbott EIA was superior to cell culture for the detection of RSV.

Antigens, Viral↗

Cytomegalovirus mononucleosis-associated antral gastritis simulating malignancy.

A 44-year-old man with epigastric pain, fever, and atypical lymphocytosis was found to have severe antral gastritis with radiologic and endoscopic features suggestive of malignancy. Histopathologic and serologic findings were diagnostic of cytomegalovirus gastric infection. Clinical involvement of the stomach in the course of cytomegalovirus mononucleosis is unique, and this case expands further the spectrum of clinical disease in the otherwise healthy adult.

Adult↗

Epidemiologic study of visceral leishmaniasis in Honduras, 1975-1983.

Between 1975 and 1983, 53 patients with parasitologically proven visceral leishmaniasis (VL) and 16 patients with suspected VL were diagnosed in Honduras. The patients' ages ranged from 3 months to 10 years, but 95% were younger than 3 years old. Since 1978, when 16 patients were reported, the yearly incidence has declined, and in 1982 only 4 patients were reported. We located and interviewed the families of 57 of the 69 patients. At the onset of illness, all 57 patients lived in rural areas, and 55 lived in southern Honduras. All the patients who were discharged from the hospital alive were still living at the time of the interview. A case-control study, using age-matched neighbors as controls, showed that patients were significantly more likely to have lived in poorly constructed, wood-stick houses. We used an indirect immunofluorescence test to analyze blood samples for Leishmania antibodies from 218 family members of patients, 170 family members of controls, and 156 children living on the island of El Tigre, where 4 of the 5 most recently diagnosed patients lived. Although 15 specimens gave a positive reaction to L. donovani antigen, each gave a stronger reaction when tested against Trypanosoma cruzi antigen, suggesting that the reactions to L. donovani were false positives. A serosurvey of 279 dogs of cases and controls and from El Tigre showed that 24 had positive reactions to L. donovani antigen, but only 4 (1.4%) had higher titers to L. donovani than to T. cruzi.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

Prevalence of Neisseria meningitidis in family members of patients with meningococcal infection.

The aim of the study was first, to determine the prevalence of Neisseria meningitidis among the family members living with patients suffering from meningococcal infections, and second, to ascertain the distribution among these family members of strains epidemiologically related to those isolated from patients. Forty-two family groups were studied and 135 nasopharyngeal samples were taken from family members living with patients. Twenty family groups were found to contain meningococcal carriers, and of these 20, 13 contained a carrier of the strain that caused the infection (65%). Among the family members who were carriers, the mother and father most frequently yielded the strain which caused the illness. The serotypes most frequently encountered both in patients and carriers were 2 and 8, as well as nontypable strains. The polyacrylamide gel electrophoretic patterns (PAGE) most frequently found were II and IV. A notable feature of the study is the high resistance of the strains to sulphadiazine, since more than 90% of the strains found in patients and more than 75% of those from carriers possessed a minimum inhibitory concentration greater than or equal to 10 micrograms/ml.

Adult↗

Flashbulb memories and other repetitive images: a psychiatric perspective.

The term "flashbulb memory" was used by Brown and Kulik in 1977 to refer to the vivid recollections that humans may have of events considered to be of particular significance to the individual or group. These memories are described as having a photographic quality and as being accompanied by a detail-perfect apparel of contextual information (weather, background music, clothes worn, etc.) pertaining to the time and place where the event was first known. They may even evoke emotions similar to the ones felt upon hearing the news. It has been suggested that flashbulb memories are formed by the activity of an ancient brain mechanism evolved to capture emotional and cognitive information relevant to the survival of the individual or group. Some of the original assumptions made by Brown and Kulik have since been challenged, but the phenomenon in question remains an important area of research. However, the latter is often marred by the fact that flashbulb memories are studied as if they were unique psychological events without parallel in clinical practice. Psychiatrists, however, should consider flashbulb memories as being members of a broad family of experiences that include drug flashbacks, palinopsia, palinacusis, posttraumatic memories, and the vivid and haunting memories experienced by subjects with some forms of mental disorder (e.g., phobias, panic attacks, obsessional disorder, phantom-limb phenomena, and depressive melancholia). All of these experiences share clinical features such as paroxysmal repetition, sensory vividness, a capacity to trigger emotions, dysphoria, and a tendency for the rememberer to shift from the role of actor to that of observer and for the reminiscence to become organized in a stereotyped narrative. Some of these clinical phenomena are discussed, and the suggestion is made that seeking phenomenological and neurobiological common denominators to all of these experiences may be a superior research strategy versus studying flashbulb memories alone.

Affect↗

Visual imagery and depersonalisation.

Twenty-eight people diagnosed with depersonalisation disorder (DD) were assessed using self-report measures of imagery ability in relation to a range of symptoms and in comparison with age- and sex-matched controls. It was found that symptoms of depersonalisation as well as other dissociative symptoms and depressed mood correlated with impaired ability to generate visual images. This was particularly evident with images pertaining to the self and other people as opposed to objects. A subgroup of 10 patients was tested on a neuropsychological battery of visual perception tests and found to be unimpaired compared with normal controls and patients with obsessive compulsive disorder, despite subjective impairments in imagery and high symptom scores. The findings add further weight to the distinctions made between imagery and perceptual processes.

Adult↗

[Prospective study of the invasive strains of Streptococcus pneumoniae isolated in 16 hospitals in Cataluna, Spain].

BACKGROUND: The increasing penicillin resistance rates of Streptococcus pneumoniae led us to review the strains isolated from usually sterile sources during 1996 in 16 hospitals of Cataluña. METHODS: A card was designed for the prospective collection of patients' data. Susceptibility to penicillin, cefotaxime and erytromicin, as well as serotypes, were studied. RESULTS: 237 S. pneumoniae strains were isolated from patients aged from one month to 95 years (19% younger than 5 years), 9.7% of adult patients being HIV antibodies carriers. Global penicillin resistance was of 35.4% (27.4% with minimal inhibitory concentration [MIC] between 0.1 and 1 microgram/ml and and 8.0% > 1 microgram/ml), but it was only of 25% in strains causing meningeal infections, and of 34.1% in those involved in respiratory processes. Paediatric patients less than five years old had a higher resistance rate (47.7%), as well as octagenarian ones (44.7%), but HIV+ patients had a lower rate (30.4%). 12.2% of strains (10% of meningeal ones) showed some degree of cefotaxime resistance but only five of them (none from meningeal origin) reached a MIC of 2 micrograms/ml. Global erythromicin resistance was 17.7% (17.1% in strains causing respiratory infections). Prevalent serotypes were 6, 9 and 14. CONCLUSIONS: The high percentage of strains, mainly from paediatric patients, with diminished penicillin, cefotaxime and erythromicin susceptibility among those causing meningitis and respiratory infections, alerts of possible therapeutic failures if empiric treatments are established in infections produced by this microorganism. For this reason, nowadays it is necessary the routine study of the susceptibility of all pathogen strains of pneumococci. Most strains (208 out of 216) causing invasive disease in our area belong to serotypes covered by the present 23-valent vaccine.

Adolescent↗

Persistent hypercalcitoninemia in patients with medullary thyroid cancer: a therapeutic approach based on selective venous sampling for calcitonin.

BACKGROUND: Persistent or recurrent medullary thyroid carcinoma (MTC) can be cured by microdissection of residual metastatic lymph nodes in the neck. Selective venous sampling can be used for localization. The aim of this study is to prospectively analyze our results with a therapeutic approach based on venous sampling, in patients with hyperthyrocalcitoninemia after thyroidectomy for MTC. METHODS: Selective venous sampling for determination of stimulated calcitonin was obtained in all patients after performing a complete laboratory and imaging workup. Patients with a gradient between the suprahepatic vein and the superior vena cava underwent unilateral or bilateral extensive lymph node dissection. We used the gradient between the right and left jugular veins to decide which side of the neck to operate. Calcitonin levels were obtained after surgery and a pentagastrin test was performed one year later if basal levels remained normal. RESULTS: Mean age of the five women with a neck gradient in the selective venous sampling who underwent neck exploration was 45 years. In all patients metastatic lymph nodes were found at the site suggested by the study. Mean positive/resected lymph nodes were 5/20. Postoperative basal and stimulated levels of calcitonin became normal in two patients at one year of follow up. CONCLUSION: Selective venous sampling is useful to localize recurrent MTC.

Adult↗