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At least 361 records · Page 20Linked to original sources
PubMed1993

A risk-benefit appraisal of transdermal estradiol therapy.

Estrogen replacement therapy (ERT) is very effective in relieving many menopausal symptoms such as hot flushes, night sweats, urogenital atrophy and psychological disturbances. Moreover, it is effective in the prevention of postmenopausal osteoporosis and has a favourable effect on some risk factors for cardiovascular disease in the long term, via several mechanisms including mediating effects on the lipid profile. Most of these beneficial effects are maintained with transdermal estradiol therapy, involving the use of a cutaneous delivery system attached to the skin which delivers a controlled rate of estradiol over a period of up to 4 days. However, the clear demonstration of a favourable effect on some risk factors for cardiovascular disease remains to be established. Transdermal administration of estradiol appears to be at least as effective as oral conjugated estrogen therapy on most of the end-points which have been evaluated, but allows a lower dose to be used, avoiding some of the metabolic adverse effects experienced with oral treatment. Endocrinological adverse effects, such as breast tenderness, breakthrough bleeding and fluid retention, are similar in both treatments, and can be minimised by dose adjustments in most cases. The most common adverse effects related to transdermal therapy are local skin reactions at the site of application. These are usually mild and transient in nature, and can be overcome by changing the site of application. Serious risks of transdermal therapy appear to be the same as those for other forms of ERT, namely an increased risk of endometrial hyperplasia and cancer with estrogen therapy alone. However, combination therapy involving the sequential administration of a progestogen has been shown to substantially reduce the risk of endometrial proliferation. The potential increased risk of breast cancer has been controversial and appears to be minimal with ERT. The role of progestogens on breast cancer risk remains controversial, but the data to date do not indicate any significant change in risk when progestogens are added to ERT.

Administration, Cutaneous↗
PubMed2002

[Chemotherapy and radiotherapy for urological cancer].

Prostate cancer, bladder cancer, renal cancer and testicular cancer are common among urological cancers. The treatment strategy for testicular cancer using chemotherapy has been well established and has been shown to be successful. Chemotherapy and radiotherapy play important roles in multidisciplinary therapy for bladder cancer. Radiotherapy is often used as a radical treatment that is practically equivalent to surgery for prostate cancer. In addition, radiotherapy is useful in cases of bone or brain metastases. In the field of chemotherapy, the development of new agents that would make breakthroughs similar to that of cisplatin is awaited. Taxanes and gemcitabine are good candidates. In the field of radiotherapy, 3D conformal radiation therapy (CRT), which has excellent beam distribution, has recently come into wide use. Moreover, brachytherapy and proton and ion beam therapy are expected to prove useful in prostate cancer therapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Patients with negative skin tests.

PURPOSE OF REVIEW: The aim of this article is to present and discuss the clinical problem of systemic anaphylaxis to Hymenoptera venoms in patients without detectable immunoglobulin E, as it appears in recent literature. Reported at variable frequency in large series of patients undergoing evaluation, systemic anaphylaxis was previously considered to reflect lost sensitization or to involve non-immunoglobulin E mediated mechanisms. Sporadic case-reports drew attention to the fact that severe or even fatal reactions may occur in patients with negative skin tests. RECENT FINDINGS: A breakthrough article by Golden et al., who performed deliberate stings on skin test negative venom anaphylaxis patients, demonstrated that clinical sensitivity was still present in a subset of these subjects and pointed out to the limitations of present diagnostic methods or reagents. New immunobiochemical methods and highly specific recombinant allergens--when all clinically relevant Hymenoptera venom allergens have been identified, cloned, sequenced and expressed in the proper system--are anticipated to increase the diagnostic yield. Non-specific mechanisms causing anaphylactoid reactions will probably explain some enigmatic, skin test negative radioallergosorbent test negative cases in the future. Occult mastocytosis, predisposing patients to anaphylactoid reactions, has been reported with increasing frequency among skin test negative patients. Lastly, other causes mimicking venom anaphylaxis may on rare occasions contribute to the problem. SUMMARY: With the present understanding of venom allergy, the practising clinician is not infrequently faced with the dilemma of the skin test negative patient. Once other identifiable causes have been carefully ruled out, referral to a specialized center for deliberate sting-challenges appears in selected cases to be a medically appropriate and ethically justified management approach.

Allergens↗
PubMed2001

Changing concepts concerning the management of vesicoureteral reflux.

PURPOSE: Conservative estimates indicate that up to 54% of patients who present with vesicoureteral reflux have dysfunction voiding. Children with voiding dysfunction and vesicoureteral reflux historically have a high breakthrough infection rate of 34% to 43%. Breakthrough infection represents significant morbidity and it is the most common indication for surgical intervention for vesicoureteral reflux. Voiding dysfunction is present in 79% of patients who proceed to reflux surgery. We evaluated the impact of pelvic floor muscle retraining combined with a medical program in patients with voiding dysfunction and vesicoureteral reflux. MATERIALS AND METHODS: Children with a history consistent with voiding dysfunction and vesicoureteral reflux were screened by uroflowmetry/electromyography, bladder scan for post-void residual urine, renal ultrasound and voiding cystourethrography. Confirmed cases of voiding dysfunction and vesicoureteral reflux were prospectively enrolled in this study. Children participated in an interactive, computer assisted, pelvic floor muscle retraining program that involved a conservative medical regimen and pelvic floor muscle retraining. All patients received prophylactic antibiotics. We evaluated the rate of breakthrough urinary tract infection, reflux outcome and surgical intervention. A literature review with the key words vesicoureteral reflux, voiding dysfunction and urinary tract infection was performed to identify historical control cases for comparison. RESULTS: Study enrollment criteria were fulfilled by 49 girls and 4 boys 4 to 13 years old (average age 8.8), representing 72 units with low grades I to II (48) and high grades III to V (24) reflux. Mean followup was 24 months. Initial uroflowmetry/electromyography and bladder scan revealed a staccato flow pattern and normal post-void residual urine in 11% of cases, staccato flow pattern and elevated post-void residual urine in 10%, flattened flow pattern and normal post-void residual urine in 28%, and flattened flow pattern and elevated post-void residual urine in 51%. Breakthrough infection developed in 5 patients (10%), including 1 in whom reflux had resolved and 1 with grade I reflux who underwent observation. The parents of 2 patients elected to complete biofeedback without surgical intervention and these patients did not have a repeat infection. Reimplantation was performed in 1 case (2%). There was resolution in 18 low and 7 high grade refluxing units, including 2 older patients with a long history of high grade bilateral disease. Average time to resolution was 7.8 months. We noted elevated post-void residual urine in 88% of the patients with high grade reflux. Average age at resolution was 9.2 years. During a 24-month period one of us (P. H. M.) noted a greater than 90% decrease in surgical intervention. CONCLUSIONS: A combined conservative medical and computer game assisted pelvic floor muscle retraining program appears to have decreased the incidence of breakthrough urinary tract infections and facilitated reflux resolution in children with voiding dysfunction and vesicoureteral reflux. Patients with high grade reflux and voiding dysfunction commonly present with elevated post-void residual urine, contraindicating the indiscriminate administration of anticholinergics. Decreasing the rate of urinary tract infections may have a dramatic impact on the need for surgical intervention and enable the reflux resolution rate to approximate that in patients without voiding dysfunction. Prospective controlled trials are needed to determine whether pelvic floor muscle retraining combined with a conservative medical regimen alters the natural history of vesicoureteral reflux in patients with voiding dysfunction.

Adolescent↗
PubMed1980

Episodic drug treatment in the management of paroxysmal arrhythmias.

The use of maintenance medication in the treatment of episodic cardiac arrhythmia is often complicated by problems of patient compliance with therapy and adverse side effects. Furthermore, repeated hospitalizations and cardioversions are both costly and inconvenient. A method of intermittent drug therapy is described in which antiarrhythmic medication is taken only at the onset of an episode of arrhythmia. This approach was effective in terminating both supraventricular and ventricular arrhythmias in 24 of 32 patients and obviated the need for hospitalization and further treatment. In cases in which maintenance therapy was required because of the frequent occurrence of arrhythmia, periodic drug therapy was still of value in the treatment of breakthrough episodes. The use of intermittent drug therapy is a safe and effective approach to the management of episodic cardiac arrhythmia and, in addition, results in significant financial saving.

Adolescent↗
PubMed1985

Chloroquine-resistant falciparum malaria in northern Malawi.

An American Peace Corps volunteer contracted chloroquine-resistant Plasmodium falciparum malaria while serving in Malawi and taking regular chloroquine prophylaxis. Resistance was confirmed by in vitro testing of his parasites for chloroquine and pyrimethamine. The possibility of Fansidar-resistant falciparum malaria was also suggested in this case. American expatriates residing in or traveling to Malawi are advised to either take both chloroquine and Fansidar, or alternatively amodiaquine or doxycycline alone. Any breakthrough of slide-proven falciparum malaria in these individuals should be seriously suspected to be chloroquine- and Fansidar-resistant malaria, and should be treated with quinine and tetracycline.

Adult↗
PubMed2006

A low rate of hepatitis B virus vaccine breakthrough infections in Mongolia.

A nation-wide hepatitis B virus (HBV) immunization program of all newborn babies was launched in Mongolia in 1991. However, the continuation of clinical icteric viral hepatitis infections in children led to the investigation to determine whether HBV breakthrough infections were occurring and if any were due to hepatitis B surface antigen (HBsAg) mutants. Hepatitis A virus (HAV) infections accounted for most of these cases with 3% of the jaundiced children shown to have acute hepatitis B. Hepatitis B vaccine protection was 93% against HBV infection and 97% against HBV carriage. A G145A "escape mutant" was found in one HBV carrier child only. Anti-HBs levels, however, were low with 85% having titers less than 100 IU/L, 46% of whom had levels less than 10 IU/L. The results from this study demonstrate that the HBV immunization program in Mongolia provides an effective level of protection. However, continued surveillance of breakthrough infections and close monitoring of "vaccine escape" mutants is required.

Adult↗
PubMed2006

Airway disease in highway and tunnel construction workers exposed to silica.

BACKGROUND: Construction workers employed in a unique type of tunnel construction known as tunnel jacking were exposed over an 18-month period to respirable crystalline silica at concentrations that exceeded the OSHA permissible exposure limit. The present study examines workplace exposures and occurrence of airway disease in these workers. METHODS: Medical and occupational histories and chest radiographs were obtained on 343 active construction workers who had worked on the site during the period in question. Chest radiographs were interpreted according to the ILO-1980 system of classification. Standardized questions were used to develop an algorithm to define symptoms consistent with asthma (SCA) and to determine these respiratory outcomes: chronic bronchitis, shortness of breath (SOB), and physician-diagnosed asthma (current vs. not current). Relationships with each of three work activities were examined: slurry wall breakthrough (SWB), chipping caisson overpour, and tunneling/mining. RESULTS: Participants included laborers, carpenters, tunnel workers, ironworkers, operating engineers, and electricians. No cases of silicosis were found on chest X-ray. Overall prevalence of chronic bronchitis, SCA, SOB, and physician-diagnosed asthma was 10.7%, 25%, 29%, and 6.6%, respectively. Odds ratios (OR) for carpenters compared to laborers were significantly elevated for chronic bronchitis, SCA, and SOB. SWB was associated with chronic bronchitis and SCA (OR 4.93, 95% CI = 1.01, 24.17; OR 3.32, 95% CI = 1.25, 8.84, respectively). The interaction between SWB, SCA, and trade was significant for carpenters (OR 6.87, 95% CI = 1.66, 28.39). Inverse trends were observed for months on the site and chronic bronchitis, SCA, and SOB (P = 0.0374, 0.0006, and 0.0307, respectively). CONCLUSIONS: Tunnel construction workers exposed to respirable crystalline silica and cement dust are at increased risk for airway disease. Extent of risk varies by trade and work activity. Our data indicate the importance of bystander exposures and suggest that tunnel jacking may be associated with greater risk compared to more traditional methods of tunnel construction. A healthy worker effect is suggested.

Adult↗
PubMed1979

Bleeding and ovulation control with use of a small contraceptive vaginal ring releasing levonorgestrel and estradiol.

Levonorgestrel and estradiol releasing contraceptive vaginal rings (CVR) with an outer diameter of 50 mm were used by twenty women. The treatment was given in three-week cycles followed by one treatment-free week. The treatment was planned to cover six cycles. All subjects kept records of bleeding and were controlled clinically in the course of treatment. Three subjects were followed by blood sampling. Plasma levonorgestrel, estradiol, progesterone and gonadotropins were determined. The subjects experienced no difficulties in using the CVR and 90 per cent continued the treatment through the whole experimental period of six months. One subject discontinued after three cycles because of irregular bleedings and one subject after five cycles because of urinary discomfort. Regular bleedings were observed only in three subjects and in nine cases the bleeding started with the CVR in situ during the last days of the three-week treatment period. Breakthrough bleeding occurred in the remaining eight subjects. The subjective side-effects were as follows: weight gain in four subjects, oedema in one subject and urinary discomfort in one subject. Pituitary function was not generally suppressed as judged by plasma gonadotropins. Out of the three subjects studied, two experienced ovulatory plasma progesterone concentrations.

Body Weight↗
PubMed1987

Permeation of protective clothing materials: comparison of liquid contact, liquid splashes and vapors on breakthrough times.

A disturbing number of common liquid chemicals permeated the best available protective clothing material when evaluated by the ASTM Standard Test Method F739-81. Since this method involved continuous liquid contact during the 3-hr test used by the Coast Guard, it was considered unusually severe. The question then arose as to whether intermittent contact--better approximating conditions likely to be encountered in real-world situations--would give usable breakthrough times (longer than pure liquid). Comparative tests were conducted with liquid exposure for 3 hr, and three levels of intermittent exposure (splashes every 15 min or every 30 min until breakthrough, or a single initial splash), and with saturated vapor at 25 degrees C and 0 degree C [decreasing amounts of exposure]. Chemicals displayed two distinct modes of behavior. In one mode, the results were as might be expected: the more prolonged or concentrated the liquid contact, the faster the breakthrough. In the other mode, there was little difference between a single splash and continuous liquid contact. In the latter case, it was observed that the liquid wet the surface of the clothing material. There are serious implications in the second mode of behaviour, not only for those wearing totally encapsulated suits, but for those wearing protective gloves. The work reported here is the basis for a proposed modification of the standard ASTM permeation test to include intermittent liquid contact (splash testing).

Chromatography, Gas↗
PubMed1994

Imported falciparum malaria in British troops returning from Kenya.

The objective of this study was to report on a breakthrough of Plasmodium falciparum infection following a military exercise in central Kenya and the treatment regimens used. A series of case reports are presented from the three UK hospitals involved. Among 150 British soldiers who had been on exercises for five weeks in central Kenya, taking proguanil/chloroquine anti-malarial prophylaxis, seven developed symptomatic falciparum malaria. Initial symptoms, which started between 2 and 10 days before their return to England, included faintness, sweating, shivering, diarrhoea, headache and myalgia. Diagnosis was delayed from between 5 and 13 days after the first symptom. One patient was severely ill with 50% parasitaemia: he required intensive care, exchange blood transfusion and haemofiltration for acute renal failure. Compliance with chemoprophylaxis was not measured and anti-mosquito measures were not generally practised. However, British Army policy was amended in June 1993 so that mefloquine will be used in future rather than proguanil/chloroquine. It was concluded therefore that even in an educated and motivated population simple preventive measures are not observed. Chemoprophylactic compliance could be improved by changing to a simpler regime. Falciparum malaria is a medical emergency that requires urgent admission for confirmation of diagnosis, supportive and curative treatment. Its presence should be suspected in any ill traveller.

Adolescent↗
PubMed2004

SARS transmission among hospital workers in Hong Kong.

Despite infection control measures, breakthrough transmission of severe acute respiratory syndrome (SARS) occurred for many hospital workers in Hong Kong. We conducted a case-control study of 72 hospital workers with SARS and 144 matched controls. Inconsistent use of goggles, gowns, gloves, and caps was associated with a higher risk for SARS infection (unadjusted odds ratio 2.42 to 20.54, p < 0.05). The likelihood of SARS infection was strongly associated with the amount of personal protection equipment perceived to be inadequate, having <2 hours of infection control training, and not understanding infection control procedures. No significant differences existed between the case and control groups in the proportion of workers who performed high-risk procedures, reported minor protection equipment problems, or had social contact with SARS-infected persons. Perceived inadequacy of personal protection equipment supply, infection control training <2 hours, and inconsistent use of personal protection equipment when in contact with SARS patients were significant independent risk factors for SARS infection.

Case-Control Studies↗
PubMed2001

[New developments in medical mycology].

Not only have the systemic mycoses clearly increased in number but also mycoses of the skin are more common than presumed in the past. Today onychomycosis is found in up to 10% of human beings. Onychomycosis can compromise quality of life markedly. Common tinea pedis is one of the most important risk factors for erysipelas of the lower legs. The clinical presentation of oral candidosis in HIV-infected patients is changing; Candida dubliniensis has been identified as another important causative microorganism. Onychomycosis today in most cases can be cured using terbinafine or itraconazole. When choosing the ideal drug in a given case, both the benefit risk ratio and the benefit cost ratio have to be taken into account. Liposomally encapsulated amphotericin B represents a major breakthrough in the treatment of systemic mycoses or fever of unknown origin. The same applies to liposomally encapsulated econazole with respect to tinea pedis. In regard to the pathogenesis of Candida infections the family of secreted aspartic proteinases plays a major role as a virulence factor and possible future target for antimycotic treatment.

AIDS-Related Opportunistic Infections↗
PubMed1976

Developing cardiac rupture as initial sign of acute myocardial infarction.

Pathological data are given of 4 patients in whom the development of cardiac rupture was the initial sign of myocardial infarction. The term 'concealed cardiac rupture' is proposed for this condition. In each instance the clinical diagnosis was 'onset of infarction', whereas the necropsy suggested that the acute onset of symptoms was caused by the start of rupture. The arguments for classifying the cases as 'concealed rupture' are (1) the lack of correlation between histological and clinical dating of the infarct, (2) the observation that the tear may take considerable time before actual epicardial breakthrough occurs, and (3) the fact that a high percentage of infarcts may pass clinically unnoticed.

Aged↗
PubMedDate not supplied

Normal perfusion pressure breakthrough occurring during treatment of carotid and vertebral fistulas.

Of the 185 carotid and vertebral fistulas treated by the authors over the past 10 years, five developed neurologic deficits after abrupt closure of their fistulas. The earliest case, treated initially by proximal surgical carotid occlusion, presented 32 years later with cerebral steal symptoms from the large, long-standing carotid cavernous fistula. Upon completion of a surgical trapping procedure, there was immediate massive cerebral edema, brain herniation, and death. In the remaining four patients (three vertebral fistulas and one with carotid cavernous fistula), all treated by transvascular embolization techniques, neurologic deficits occurred coincidentally with the abrupt closure of the fistula and resolved with reestablishment of fistula flow. This indicated that the cerebral vasculature is unable to tolerate the reestablishment of normal cerebral perfusion after abrupt closure of the fistula. All four patients were treated with staged or slow occlusion of their fistulas, which resulted in complete fistula closure without permanent neurologic sequelae. All five patients who developed symptoms consistent with normal perfusion pressure breakthrough had large, long-standing fistulas, ranging in duration from 9 to 32 years. Two of the five patients developed slowly progressive neurologic deficits consistent with cerebral steal prior to treatment. This sign was not observed in the 180 patients who did not develop symptoms during treatment. We conclude that patients with carotid or vertebral fistulas of long duration, particularly those with cerebral steal symptoms, are at risk to develop neurologic deficits related to perfusion breakthrough if their fistulas are abruptly closed. Staged or gradual closure may prevent this potentially devastating complication.

Adult↗