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Biomedical subjects

P Rivera

Publications and source records attributed to P Rivera.

At least 37 records · Page 2Linked to original sources
PubMed1997

Benefit of two-step PPD testing of new employees at a New York City hospital.

BACKGROUND: Recent concern about nosocomial transmission of tuberculosis has led hospitals to scrutinize employee tuberculin conversion rates. The Centers for Disease Control and Prevention recommends two-step testing of new employees to limit the booster phenomenon. The cost of such a program and its subsequent yield have not recently been examined. METHODS: Employee health records were retrospectively reviewed of persons hired from 1993 and 1994 at St. Clare's Hospital in New York City, all of whom received two-step testing at time of initial employment. RESULTS: Of 262 new employees, 107 (41%) had positive tuberculin results on initial testing. The results of 15 (9.7%) of the remaining 155 patients became positive on two-step testing administered 1 week later. Persons with a positive second test result were significantly more likely to be male or foreign born or to have received previous bacille Calmette-Guérin vaccination. Identification of these 15 persons and exclusion of them from probable subsequent conversion prevented an almost 50% increase in the annual conversion rate at our hospital, from 3.2% to 4.7%. CONCLUSION: Two-step tuberculin testing is an essential means of identifying persons with a baseline positive tuberculin test result, thus allowing accurate reporting of subsequent employee tuberculin conversions.

Adult↗
PubMed1997

Biological and chemical study of paico (Chenopodium chilense, Chenopodiaceae).

The methanolic extract of the aerial portion of Chenopodium chilense Schrad., used in Chilean traditional medicine as a remedy for stomach-ache, has been found to exert the major spasmolytic activity in acetylcholine contracted rat ileum. This extract, with a complex flavonoid patterns on thin layer chromatography (TLC) analysis, is practically non-toxic both for rats and brine shrimp Artemia salina in acute toxicity test.

Acetylcholine↗
PubMed1997

Does a cheaper mask save money? The cost of implementing a respiratory personal protective equipment program.

OBJECTIVE: To determine the annual cost of implementing and maintaining a respiratory personal protective equipment (PPE) program at an urban hospital. SETTING: St Clare's Hospital and Health Center, a 250-bed hospital in Manhattan that treats 60 to 100 cases of tuberculosis annually. METHODS: Review of Purchasing Department records for all masks acquired by the hospital from 1992 to 1995, and an estimate of administrative time spent developing and implementing the guidelines recommended by various agencies during the study interval. RESULTS: Respiratory isolation was provided for 6,360 to 10,883 days annually during the 4-year interval. Yearly costs for the PPE program ranged from $86,560 to $175,690. Of note, the daily cost for a respiratory isolation day decreased dramatically between 1994 and 1995 ($25/day to $13/day), when the high-efficiency particulate air-filter (HEPA) respirator was used by all staff. The decrease occurred because of lower administrative costs and a sharp decrease in the numbers of HEPA units purchased. Objective measures of worker compliance with HEPA respirators demonstrated the decrease was not due to less HEPA use but rather that employees were using each HEPA unit for several weeks, as recommended. CONCLUSION: We found a significant decrease in cost in the second year of our HEPA program due to increasing employee familiarity with the program. Newly approved, cheaper, but less durable, N-95 masks are unlikely to withstand multiple wearings and may be discarded after a few uses. Thus, cheaper masks may result in a more expensive PPE program.

Cost-Benefit Analysis↗
PubMed1997

Risk of tuberculin conversion according to occupation among health care workers at a New York City hospital.

Concern about the risk to health care workers of occupationally acquired tuberculosis has resulted in extensive and frequently revised guidelines from the Centers for Disease Control and Prevention (CDC). Most recent studies, however, have determined that community, rather than occupational, exposure is the more significant risk for tuberculin conversion. To assess the relative contribution of community versus occupational risk, we reviewed the health records of 1,303 persons employed from 1991 to 1994 at St. Clare's Hospital in New York City, a hospital with a high tuberculosis case-rate. Demographic information included age, gender, postal zone of residence, country of birth, and BCG vaccination status, while occupations were placed into one of five groups. In multivariate analysis, occupation was significantly associated with risk of tuberculin conversion, while postal zone of residence was not. The group that included housekeeping, laundry, and security personnel and the physician-nurse group had the highest conversion rates. After implementation of CDC guidelines, there was a significant improvement in the employee tuberculin conversion rate. At our hospital, occupation was strongly associated with risk of tuberculin conversion.

Female↗
PubMed1997

[Cancer of the prostate: evaluation of the expression of the mutated protein of the 53 tumor suppressor gene].

UNLABELLED: Prostate cancer is the most common tumour in men, and is most frequently established late in life. The objective of the article is to determine the protein expression of gene p53 in prostate cancer and to correlate the findings with clinical, morphological and epidemiological parameters. MATERIAL AND METHODS: Immunohistochemical techniques with monoclonal antibody used to study the gene p53 expression. The study included 35 prostate carcinoma: 4 cases in stage A; 5 cases in stage B; 12 in stage C and 14 in stage D. The control group consisted in 10 benign prostate hyperplasia. Average age was 66.8 (SD +/- 6.7 years). RESULTS: Positive staining for gene p53 protein was seen in 11 of the 35 cases (31.4%). All stage A and B tumours were negative; however, stage C and D tumours were positive in 16 and 64% cases respectively. In the control group all cases were gene p53 negative. No statistical relationship was seen between Gleason Index and positive results for p53. There was a significant difference between gene 53 expression and clinical stage. CONCLUSIONS: Results show that the immunohistochemical expression of gen p53 mutated protein keeps no relation to Gleason's rating index and is seen with significantly higher frequency in advanced, primarily stage D tumours.

Adenocarcinoma↗
PubMed1997

[Collagenous colitis: presentation of 12 cases].

Collagenous colitis (CC) is a cause of chronic aqueous diarrhea with normal radiologic study and endoscopic appearance of the colonic mucosa. Histologically, it is defined by the presence of a thickened subepithelial collagenous band and inflammatory changes of the mucosa. The cause of CC is currently unknown, although several mechanisms have been proposed, such as an inflammatory, autoimmune, origin, disregulation in collagen synthesis, plasma vasculosis and a possible role of bacterial or drug toxins. The clinicopathological data of 12 patients (9 females and 3 males) with a mean age of 52.4 years diagnosed by histologic criteria are presented. Aqueous diarrhea was observed in all the patients with a mean number of 5.4 stools/day during a time period between 3 weeks and 10 years (mean, 14.7 months). In a 6 patients allergies and/or associated diseases, mainly rheumatologic diseases were found. Laboratory and endoscopic data were normal or unspecific, with colon biopsy being carried out in all the patients. Several treatments were tested with good response with sulphasalazine derivatives, corticoids, antibiotics, and mebeverine, with no solution to the diarrhea in 2 patients. A review of the literature is also provided.

Adult↗
PubMed1997

Rotavirus and coronavirus outbreak: etiology of annual diarrhea in Costa Rican children.

In Costa Rica, an annual outbreak of infant diarrheal disease (December and January) was reported since 1976, and rotavirus was incriminated later as the main etiological agent (1976-1981). Apparently the disease has not been systematically studied in Costa Rica after 1981. For that reason the occurrence of the outbreak was retrospectively documented for 1993-1995 and etiology was studied in 48 children treated for diarrhea at the Nacional Children Hospital (capital city of San Jose) during December, 1994 and January, 1995. Rotavirus (33%) and coronavirus (27%) were the main agents. To our knowledge, this is the first time that these viruses are incriminated in an outbreak of diarrhea.

Child↗
PubMed1996

Pneumococcal keratitis, bacteremia, and septic arthritis in an asplenic patient.

We report the case of a 66-year-old black woman who presented with concomitant acute infectious keratitis, bacteremia, and septic arthritis caused by Streptococcus pneumonia. The septic arthritis resolved rapidly with surgical drainage and intravenous antibiotics, but despite aggressive topical and intravenous antibiotic therapy for the infectious keratitis, the cornea perforated, the patient developed endophthalmitis, and the eye eventually was eviscerated. To the best of our knowledge this is the first reported case of this nature. This patient had undergone splenectomy > 50 years prior to developing these infections. Although the risk of serious infection in clinically significant bacteremia is greatest in the perioperative period after splenectomy, these patients are at increased risk of such events for a lifetime. Because encapsulated bacteria, especially Pneumococcus, pose the greatest risk of sepsis and infection in asplenic patients, pneumococcal vaccination of penicillin prophylaxis must always be considered in these patients. A careful and complete medical history and systemic evaluation remain a crucial element of the evaluation and management of serious infectious keratitis.

Aged↗
PubMed1996

[Splenic infarction].

A 53-year-old male suffered splenic infarction etiologically related to atrial fibrillation and non-obstructive hypertrophic cardiomyopathy. The main clinical manifestations were a one-month history of epigastric and left upper quadrant pain, with tenderness to palpation in the later zone. Laboratory tests revealed a slight leucocytosis (14.700) with left shift and a marked increase in LDH concentration (945 IU). Abdominal CAT and arteriography established the diagnosis, Echography proved normal. Patient evolution was satisfactory with conservative medical treatment. We conclude that splenic infarction should be considered in all cases of acute or chronic pain in the left hypochondrium. The diagnosis is established by CAT, arteriography and hepatosplenic gammagraphy. Medical management is initially advocated, surgery being reserved for those cases involving complications or in which diagnosis is not clear. Emphasis is placed on the main etiological, clinical, diagnostic and management characteristics of splenic infarction.

Angiography↗
PubMed1996

[Response of lymphocytes and cytokines in patients with superficial bladder cancer treated with 1 mg of BCG vaccine instillations].

It was carried out a study of lymphocytes CD3, CD8 and cytokines in the blood of 13 patients, with superficial bladder cancer, and treated by instillations with BCG vaccine, with a dose of 1 mg. in an annual scheme, being related them before and after treatment. A control group of 10 patients without bladder cancer and without vaccine instillations were compared. The measurings took place in a blind way, previous to BCG treatment, 15 days, 3 days, 3 months, 6 months and 12 months of treatment. It was observed in postBCG treatment, a significative increase in the count of CD3 lymphocytes and the CD4/CD8 cociente (both, P < 0.05). Concerned to cytokines, a significative increase was only demonstrated by interleukin-2 in the post BCG group (P < 0.05). In both (lymphocytes and cytokines) the control groups didn't demonstrate statistics signification. The studies where analysed by means of ANDEVA test, under 2 x 2 cross over design, student t and no parametric tests. In conclusion, bladder instillations of 1 mg. of BCG vaccine as prophylactic treatment of superficial bladder cancer, it's capable of developing lymphocytic answer and stimulate the increase of interleukin-2 in the serum.

Adjuvants, Immunologic↗
PubMed1995

Dramatic decrease in tuberculin skin test conversion rate among employees at a hospital in New York City.

BACKGROUND: The Centers for Disease Control and Prevention recently issued updated guidelines for preventing the transmission of tuberculosis in health care facilities. Many recommendations, including the use of high-efficiency particulate air filter respirators, are expensive to implement and of unproven efficacy. We therefore reviewed the tuberculin skin test conversion rate among our employees from 1991 to 1993, before introduction of high-efficiency particulate air filter respirators. During this period, several other improvements in tuberculosis control were implemented. METHODS: Employee tuberculin test conversion rates were reviewed by 6-month interval from 1991 to 1993. RESULTS: Throughout the study period, several tuberculosis control measures were implemented, including early isolation of patients with suspected cases of tuberculosis in rooms with negative-pressure ventilation, placement of germicidal UV light fixtures into patient rooms and common areas, and use of Technol shields (Technol, Inc., Fort Worth, Texas) (1991), particulate respirators (1992), and dust-mist-fume respirators (1993). With these improvements, the conversion rate among employees fell from 20.7% in the first 6 months of 1991 to 5.8% in the latter half of 1993. CONCLUSIONS: The rate of skin test conversion among our employees decreased before introduction of high-efficiency particulate air filter respirators. This suggests that nosocomial spread of tuberculosis can be decreased by means of previously established, less costly methods.

Cross Infection↗
PubMed1995

Prevalence of PPD positivity among new employees at a hospital in New York City.

OBJECTIVE: To determine the prevalence of tuberculin reactivity among all new employees at a hospital in New York City. DESIGNS: Prospective measurement of purified protein derivative (PPD) status in consecutive new employees at a hospital in New York City from 1991 to 1993. All employees are tested as part of a preemployment physical, assuring complete compliance. Aplisol (Parke-Davis, Morris Plains, NJ) was used in 1991 and 1992, and Tubersol (Connaught, Swiftwater, PA) in 1993. Tests were applied and interpreted by trained employee health personnel. RESULTS: Of 313 consecutive new employees, comprising all job categories, 40% were PPD positive at time of initial hire, including 20% of US-born and 70% of foreign-born employees. Of 114 persons who had received BCG vaccination, 67% were PPD positive. By multivariate regression analysis, age, BCG vaccination history, and foreign country of birth were independent predictors of a reactive PPD test. CONCLUSIONS: The high prevalence of tuberculin reactivity may reflect high rates of Mycobacterium tuberculosis infection and disease in the community, complicating interpretation of the efficacy of Centers for Disease Control and Prevention (CDC) guidelines to prevent the spread of tuberculosis in healthcare facilities.

Adolescent↗
PubMed1994

[Evaluation of prostatic specific antigen after a digital rectal examination: experience with 36 patients].

Levels of prostatic specific antigen may be modified with procedures over the prostatic gland. We measured this antigen in 36 hospitalized patients before and immediately after a digital rectal examination. Antigen levels were 8.3 +/- 21.3 ng/ml before and 13.8 +/- 27.5 ng/ml after the examination (NS). It is concluded that digital rectal examination did not modify antigen levels in our sample.

Adult↗
PubMed1994

[Nucleolar organizer region in bladder cancer. Relationship with histologic grade, stage, and prognosis].

By means of silver staining, 31 transitional bladder cancer were studied in order to quantify the number of the nucleolar organizer regions and ist relationship with histological grade, tumoral stage and prognosis of the disease. The group under study was composed by 18 cases superficial carcinomas (T1 stage), and 13 deep carcinomas (T2 and T3b stage). A significant difference between normal and neoplastic bladder mucosa, and between T1 and t3b stage was demonstrated (p = 0.03). However, ther was not difference between patients whom develop recurrences. In this study we were not able to demonstrate the importance of the count of the nucleolar organizer regions as prognostic factor in bladder cancer.

Aged↗
PubMed1993

Immunoelectron microscopy of parainfluenza virion glycoproteins with polyclonal and monoclonal antibodies: movement of glycoprotein with monoclonal antibody.

Two glycoproteins (HN and F) of parainfluenza virus were immunogold-labeled with polyclonal and monoclonal antibodies, respectively, and their labeling patterns were compared. Both glycoproteins HN and F were efficiently and homogeneously labeled with polyclonal antibodies, whereas they were labeled much less and heterogeneously with monoclonal antibodies. When either protein was initially labeled with monoclonal antibody, and then the other one, with polyclonal antibody, immunolabels of two glycoproteins were almost completely segregated. Although this segregation deformed virion morphology, it supported the concept of monoclonal antibody-mediated movements of glycoproteins.

Animals↗
PubMed1993

[Microdoses of BCG vaccine for prophylaxis in bladder cancer stage T1].

A prophylaxis with a minidose of BCG Vaccine (1 mgr.) is performed in vesical instillation during one year, to 108 patients bearing bladder cancer in the stage T1. In the first month the instillations are once a week, each fifteen days the second and third month and then, once a month for one year. An 19.4% of recurrences is obtained with an general average observation time of 37.3 months as well as an important increase of muster populations of T lymphocytes and a positive test of dinitroclorobenzene. As complications we have obtained an inguinal BCG adenitis and in a few cases disury and frequency for two or three days. We conclude that the doses of the BCG vaccine used during the period of one year, is satisfactory in the reduction of recurrences and without important complications.

Administration, Intravesical↗