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71.
OBJECTIVE: To determine the extent of clinical knowledge of HIV/AIDS that physicians in Barbados have and their attitudes towards persons living with HIV/AIDS. METHODS: In 2000 the Barbados Association of Medical Practitioners conducted a survey in order to assess its members' views on HIV/AIDS issues. Over a two-month period 203 physicians (76% of all those practicing in the country) were interviewed. The survey included physicians working in private practice and the public sector. They were surveyed individually concerning their attitudes towards counseling as well as their clinical knowledge, perception of safe practices, fear of occupational exposure, views on ethical issues, experience treating HIV/AIDS patients, and background with HIV/AIDS continuing education. RESULTS: In comparison to physicians who had graduated in later years, physicians who had graduated in 1984 or earlier had seen fewer HIV/AIDS clients, had lower levels of knowledge about the disease, were more likely to test for HIV/AIDS without informed consent, and were less likely to have ever attended a continuing education training course on HIV/AIDS. Overall, knowledge of the clinical indications of HIV/AIDS was low, and 76% of the physicians did not think they had adequate counseling skills. Over 80% of the physicians were comfortable looking after HIV/AIDS patients. While 95% of the physicians would not release HIV test results without a patient's consent, 33% would test, without consent, a seriously ill patient, and 15% would test without consent a patient upon whom they had to perform an invasive procedure if they perceived the patient to be from a high-risk population such as gay men or commercial sex workers. Only 53% of the physicians had attended an HIV/AIDS in-service training program between 1995 and 1999. CONCLUSIONS: Physician training in Barbados should focus on all aspects of HIV/AIDS care, including clinical and emotional factors. Attendance at such training should be mandatory for public sector physicians, and medical school curricula need to be examined to ensure their HIV/AIDS content is current and comprehensive.  相似文献   
72.
Colorectal cancer prevention.   总被引:10,自引:0,他引:10  
Colorectal cancer is the second leading cause of mortality in the United States. In the United States, the cumulative lifetime risk of developing colorectal cancer for both men and women is 6%. Despite advances in the management of this disease, the 5-year survival rate in the United States in only 62%. Because only 38% of patients are diagnosed when the cancers are localized to the bowel wall, it is likely that widespread implementation of screening could significantly improve the outcome. Colorectal cancer screening is cost effective, irrespective of the methods used. In addition to currently available methods (fecal occult blood, flexible sigmoidoscopy, colonoscopy, and double contrast barium enema), computed tomographic colonography (virtual colonoscopy) and stool-based molecular screening are under development. Four classes of chemopreventive compounds have demonstrated efficacy in reducing recurrent colorectal adenomas and/or cancer in randomized, controlled trials. They are selenium, calcium carbonate, hormone replacement therapy, and nonsteroidal anti-inflammatory drugs. The mechanisms of action of nonsteroidal anti-inflammatory drugs include inhibition of the cyclooxygenase system as well as cyclooxygenase-independent effects. Considerable effort is being expended to define chemopreventive activity, optimal dose, administration schedule, and toxicity for the coxibs in adenoma recurrence prevention trials. The threshold for tolerating toxicities is very low in asymptomatic individuals at minimally increased risk for colorectal neoplasia.  相似文献   
73.
Most patients with Hodgkin's disease (HD) are cured with chemotherapy and/or radiotherapy. However, half of those with advanced stage disease (IIIB, IV) do not respond adequately to treatment or relapse. Salvage therapy used in such cases gives from 10% to 50% complete remission but only 10% long term survival. The results of bone marrow transplantation reported in acute leukemia and non-Hodgkin's lymphoma encouraged some authors to develop this new therapeutic strategy in Hodgkin's disease. In the early 1980's promising results were achieved when refractory and relapsed patients were selected to receive myeloablative therapy followed by bone marrow transplantation. Today, high dose chemotherapy with hematopoietic stem cell transplantation (HSCT) is used more and more often in poor prognosis Hodgkin's disease.  相似文献   
74.

Ethnopharmacological relevance

Lignosus rhinocerus (known locally as ‘Tiger Milk mushroom’) is the most important medicinal mushroom used by the indigenous communities of Malaysia to treat fever, cough, asthma, cancer, food poisoning and as a general tonic. The sclerotium of the mushroom is the part with medicinal value. Lignosus rhinocerus was hitherto unexploited commercially because of limited supply. Recently, the mushroom was successfully cultivated.

Materials and methods

Sprague Dawley rats (5 rats/group/sex) were fed orally with 250, 500 and 1000 mg/kg TM02, 1000 mg/kg TM03 as well as 1000 mg/kg wild type Lignosus rhinocerus sclerotial powder. Sclerotial powder was orally administered once daily and consecutively for 28 days. Body weight of each animal was measured and any gross behavioral change was observed daily. Hematological and clinical biochemical parameters as well as histopathological analysis were carried out on 29th day.

Results

The results showed that oral administration of the sclerotial powder at daily dose of up to 1000 mg/kg had no adverse effect on the growth rate, hematological and clinical biochemical parameters (including renal and liver function parameters). Histological studies showed that the treatments did not induce any pathological changes in the liver, kidney, heart, spleen and lung of the animals.

Conclusion

In conclusion, our results show that there was no treatment-related sub-acute toxicity in rats following 28-days oral administration of 250, 500 and 1000 mg/kg TM02, 1000 mg/kg TM03 as well as 1000 mg/kg wild type Lignosus rhinocerus sclerotial powder. As the highest tested dose of 1000 mg/kg was not associated with any toxicity concern, the NOAEL dose is higher than 1000 mg/kg.  相似文献   
75.
In mammalian cells, DNA damage response initiates repair by error-free homologous recombination (HRR) or by error-prone non-homologous end joining (NHEJ). DNA damage is detected by PARP proteins that facilitate this repair, both in normal cells and in cancer cells. Cells containing BRCA1/2 mutations have an HRR-deficient repair mechanism which may result in unrepaired one-ended double-strand breaks and stalled replication forks, considered as the most lethal cell damage. Here, we review the state of the art of the role of Poly (ADP-ribose) polymerase (PARP) inhibitors as a precision-targeted anticancer drug in BRCA1/2-mutated female breast cancer. Although knowledge is incomplete, it is assumed that the main role of the archetype PARP1 in the cell nucleus is to detect and adhere to single-strand breaks. This mediates possible damage repair, after which cells may continue replication; this process is called synthetic lethality. As for PARP clinical monotherapy, progression-free survival has been observed using the FDA- and EMA-approved drugs olaparib and talazoparib. In the case of combined drug therapy, a synergy has been demonstrated between veliparib and platinum drugs. Information regarding adverse effects is limited, but hematological effects have been described. However, there is need for multicenter trials, preferably conducted without commercial guidance and funding. Some of the available trials reported resistance to PARP inhibitors. In this review, we also describe the various causes of resistance to PARP inhibitors and research indicating how resistance can be overcome.  相似文献   
76.
Tacrolimus (TAC) is a dose‐dependent immunosuppressor with considerable intrapatient variability (IPV) in its pharmacokinetics. The aim of this work is to ascertain the association between TAC IPV at 6 months after liver transplantation (LT) and patient outcome. This single‐center cohort study retrospectively analyzed adult patients who underwent transplantation from 2015 to 2019 who survived the first 6 months with a functioning graft. The primary end point was the patient’s probability of death and the secondary outcome was the loss of renal function between month 6 and the last follow‐up. TAC IPV was estimated by calculating the coefficient of variation (CV) of the dose‐corrected concentration (C0/D) between the third and sixth months post‐LT. Of the 140 patients who underwent LT included in the study, the low‐variability group (C0/D CV < 27%) comprised 105 patients and the high‐variability group (C0/D CV ≥ 27%) 35 patients. One‐, 3‐, and 5‐year patient survival rates were 100%, 82%, and 72% in the high‐variability group versus 100%, 97%, and 93% in the low‐variability group, respectively (p = 0.005). Moreover, significant impaired renal function was observed in the high‐variability group at 1 year (69 ± 16 ml/min/1.73 m2 vs. 78 ± 16 ml/min/1.73 m2, p = 0.004) and at 2 years post‐LT (69 ± 17 ml/min/1.73 m2 vs. 77 ± 15 ml/min/1.73 m2, p = 0.03). High C0/D CV 3–6 months remained independently associated with worse survival (hazard ratio = 3.57, 95% CI = 1.32–9.67, p = 0.012) and loss of renal function (odds ratio = 3.47, 95% CI = 1.30–9.20, p = 0.01). Therefore, high IPV between the third and sixth months appears to be an early and independent predictor of patients with poorer liver transplant outcomes.

Abbreviations

BPAR
Biopsy proven acute rejection
BMI
Body mass index
CKD‐EPI
chronic kidney disease epidemiology collaboration
CV
coefficient of variation
C0/D
dose‐corrected concentration
CMV
cytomegalovirus
eGFR
estimated glomerular filtration rate
HR
hazard ratio
HCC
hepatocellular carcinoma
ICU
intensive care unit
IPV
intrapatient variability
i.v.
intravenously
LC–MS/MS
liquid chromatography‐ tandem mass spectrometry
LT
liver transplantation
MELD
model for end‐stage liver disease
MMF
mycophenolate mofetil
NASH
Non‐Alcoholic Steatohepatitis
OR
odds ratio
PCR
polymerase chain reaction
SD
Standard Deviation
TAC
tacrolimus
3–6 M
three–six months
Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
There is high intrapatient variability of tacrolimus and its correlation with liver transplantation (LT) outcomes.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
Could the intrapatient variability of tacrolimus between months 3 and 6 post‐LT be a potential prognostic tool for poor outcomes?
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Those patients with dose‐corrected concentration coefficient of variation greater than or equal to 27% between months 3 and 6 post‐LT have worst overall survival and impaired renal function.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
If we promptly identify those patients, a closer therapeutic drug monitoring program should be imperative with the possibility to make therapeutic interventions to improve outcomes.  相似文献   
77.
INTRODUCTIONLinkage to care among individuals with substance misuse remains a barrier to the elimination of the hepatitis C virus (HCV). We aimed to determine whether point-of-care (PoC) education, screening and staging for liver disease with direct access to hospitals would improve linkage to care among this group.METHODSAll participants were offered PoC education and HCV screening. HCV-positive participants were randomised to standard care (controls) or direct access, which provided a direct pathway to hospitals. Linkage to care was determined by reviewing electronic medical records. Linkage of care cascade was defined as attendance at the specialist clinic, confirmation of viraemia by HCV RNA testing, discussion about HCV treatment and initiation of treatment.RESULTS351 halfway house residents were screened. The overall HCV prevalence was 30.5% (n = 107), with 69 residents in the control group and 38 in the direct access group. The direct access group had a significantly higher percentage of cases linked to specialist review for confirmatory RNA testing (63.2% vs. 40.6%, p = 0.025), HCV treatment discussion (p = 0.009) and treatment initiation (p = 0.01) compared to the controls. Overall, only 12.6% (n = 13) had treatment initiation during follow-up. PoC HCV screening with direct access referral had significantly higher linkage to HCV treatment initiation (adjusted odds ratio 9.13, p = 0.005) in multivariate analysis.CONCLUSIONPoC HCV screening with direct access improves linkage to care and simplifies the HCV care cascade, leading to improved treatment uptake. PoC education, screening, diagnosis and treatment may be an effective strategy to achieving HCV micro-elimination in this population.  相似文献   
78.
79.
The isolation of group specific B substance from human stomach juice is described. The substance is carbohydrate-like in nature and is as potent as the carbohydrate-like substance group A isolated from commercial pepsin and peptone respectively.  相似文献   
80.
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