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PubMed1997

Infection prevention and control in the long-term-care facility. SHEA Long-Term-Care Committee and APIC Guidelines Committee.

More than 1.5 million residents reside in US nursing homes. In recent years, the acuity of illness of nursing home residents has increased. Long-term-care facility residents have a risk of developing nosocomial infection that is similar to acute-care hospital patients. A great deal of information has been published concerning infections in the long-term-care facility, and infection control programs are nearly universal. This position paper reviews the literature on infections and infection control programs in the long-term-care facility, covering such topics as tuberculosis, bloodborne pathogens, epidemics, isolation systems, immunization, and antibiotic-resistant bacteria. Recommendations are developed for long-term-care infection control programs based on interpretation of currently available evidence. The recommendations cover the structure and function of the infection control program, including surveillance, isolation, outbreak control, resident care, and employee health. Infection control resources also are presented.

Cross Infection↗
PubMed1999

Hippocampal synaptic plasticity in streptozotocin-diabetic rats: impairment of long-term potentiation and facilitation of long-term depression.

Streptozotocin-diabetic rats, an animal model for diabetes mellitus, show learning deficits and impaired long-term potentiation in the CA1-field of the hippocampus. The present study aimed to further characterize the effects of streptozotocin-diabetes on N-methyl-D-aspartate receptor-dependent long-term potentiation in the CA1-field, to extend these findings to N-methyl-D-aspartate receptor-dependent and independent long-term potentiation in other regions of the hippocampus and to examine effects on long-term depression. First, the effect of diabetes duration on long-term potentiation in the CA1-field was determined. A progressive deficit was observed after a diabetes duration of six to eight weeks, which reached a maximum after 12 weeks of diabetes and remained stable thereafter. Next, long-term potentiation was examined in the dentate gyrus and in the CA3-field after 12 weeks of diabetes. Both were found to be impaired compared to controls. Finally, long-term depression was examined in the CA1-field of the hippocampus after 12 weeks of diabetes and found to be enhanced in slices from diabetic rats compared to controls. Changes in synaptic plasticity were observed in hippocampal slices from streptozotocin-diabetic rats. Expression of N-methyl-D-aspartate receptor-dependent long-term potentiation was impaired in the CA1-field and dentate gyrus and expression of N-methyl-D-aspartate receptor-independent long-term potentiation was impaired in the CA3-field. In contrast, expression of long-term depression was facilitated in CA1. It is suggested that this combination of changes in plasticity may reflect alterations in intracellular signalling pathways.

Animals↗
PubMed1996

Messengers from the synapses to the nucleus (MSNs) that establish late phase of long-term potentiation (LTP) and long-term memory.

The late stage of long-term potentiation (LTP) and long-term memory is believed to be largely governed by altered gene expression for its generation and maintenance, while the early stages of LTP and memory are controlled mainly by the phosphorylation-dephosphorylation of the synaptic proteins. For the altered gene expression, synaptic information must be transmitted from the synaptic sites to the nucleus. This article describes the presence of specific messenger molecules that transmit synaptic information to the nucleus; these molecules are referred to as MSNs (Messengers from Synapse to the Nucleus). In addition, recent studies have indicated that certain transcription factors localize at postsynaptic sites as well as the nucleus, and may function as MSNs.

Animals↗
PubMed1991

Prescription and intake patterns in long-term and ultra-long-term benzodiazepine treatment in primary care practice.

Pharmacoepidemiological data show that long-term treatment accounts for a considerable part of benzodiazepine prescriptions in primary care practice. Prescription and intake patterns were, therefore, investigated in a study of 196 patients who had been treated with benzodiazepines for longer than six months by internists or general physicians in private practice. Patients were 64 years of age on average, half of them being 65 years or older. Females were in the majority (73.5%). The average duration of tranquilizer or hypnotic intake was 11.0 years, or 5.3 years for the current benzodiazepine medication. The mean daily dose was 9 mg diazepam equivalent. All benzodiazepine hypnotics and 61% of benzodiazepine tranquilizers had been prescribed solely for night-time use. Only 6% of the patients were taking benzodiazepines as single medication: on average they were taking 3.1 additional types of medication for other conditions, these being predominantly cardiac and antirheumatic/analgesic in nature. One in five patients was taking additional psychotropic medication. The compliance coefficient was on average 0.8, showing that patients did not tend to abuse benzodiazepines, with noncompliance generally being similar to noncompliance with other forms of medication.

Adult↗
PubMed1977

Ultrastructure of muscle biopsies in recent, short-term and long-term juvenile diabetes.

Muscle biopsies from juvenile diabetics were studied by electron microscopy and the results correlated to earlier published light microscopical abnormalities of the same biopsies. A total of 32 striated muscle biopsies from 29 juvenile recent, short-term and long-term diabetes were examined. The ages ranged from 16 to 43 years with a diabetes duration from 1 week to 32 years. The material was compared with biopsies from healthy persons of the same ages. The electron microscopy revealed degenerative changes of the striated muscle fibres which signify a neurogenic atrophy. No myopathic alterations were found. The capillaries in both the recent and long-term diabetics showed an extremely pronounced pinocytosis indicating an increased metabolic activity. In the long-term group the intramuscular capillaries both from upper and lower extremities displayed a definitely thickened basement membrane. In the recent and short-term group the capillary wall alterations were debatable. The motor end plate in the recent diabetics revealed minimal alterations. Contrary to this the long-term group showed severe alterations with occasional disappearance of the nerve fibres.

Adolescent↗
PubMed2002

Industrial hygiene sampling for airborne TDI in six flexible slabstock foam manufacturing facilities in the United States: a comparison of the short-term and long-term sampling data.

A majority of all the flexible polyurethane foams are produced by the continuous slabstock process using toluene diisocyanate (TDI) and polyether polyol. The commercially available TDI product is predominantly an 80:20 mixture of the 2,4-TDI and 2,6-TDI isomers. TDI can be used in many applications, but the market is dominated by the flexible slabstock foam industry. Even though there has been a considerable amount of industrial hygiene sampling conducted for airborne TDI in this industry, the focus of the sampling has generally included long-term (time-weighted average) monitoring with a limited amount of sampling for short-term (peak) episodes. By conducting only long-term sampling, which averages the exposure over some extended time period, these short-term episodes (i.e., tasks or activities) of peak exposure were often not characterized. To investigate whether long-term sampling was adequately predictive of short-term excursions, simultaneous (side-by-side) short-term and long-term breathing zone samples were collected on 31 flexible slabstock foam line employees at six manufacturing facilities throughout the United States. Four hundred three short-term samples averaging 15 minutes in length, and 78 long-term samples averaging 124 minutes in length were collected for four operator categories. From these 78 long-term samples, 31 eight-hour TWAs were projected (assuming no further exposure to airborne TDI for the remainder of the work shift) for comparison to the short-term samples. Based on the data collected, compliance with the current ACGIH TLV TWA of 5 ppb would also ensure compliance with the OSHA PEL-C of 20 ppb in a majority of the cases associated with the flexible slabstock foam industry provided that (1) the TLV TWA accounted for the 2,6-TDI isomer in addition to the 2,4-TDI isomer (at this time, exposure limits are published for only the 2,4-TDI isomer), and (2) the TLV TWA was compared to the partial shift TWA measured over the operational time of the workday rather than as an average over an eight-hour workday. Further, exceedences of the 20 ppb PEL-C did occur (e.g., when the foam line tunnel was entered, where there was an "upset" condition, or where there was close contact with hot [fresh cut] buns), but can be protected against with (1) improved work practices, (2) engineering controls, and (3) respiratory protection.

Air Pollutants, Occupational↗
PubMed1978

Genetic dissection of short-term and long-term facilitation at the Drosophila neuromuscular junction.

Transmitter release at the Drosophila larval neuromuscular junction may be increased by previous activity of the nerve. This facilitation phenomenon involves at least two processes, one short-term and other long-term. These are shown to based on different mechanisms because (i) a mutant was found that had abnormal long-term facilitation but normal short-term facilitation; and (ii) long-term facilitation was eliminated by tetrodotoxin or by removing external Na+ but short-term facilitation was not. In long-term facilitation, there was a prolonged release of transmitter due to a prolonged Ca2+ sensitivity of the presynaptic terminal after each nerve stimulus. The cause of this is probably accumulation of Na+ inside the nerve terminal.

Animals↗
PubMed2003

Activation of a tyrosine kinase-MAPK cascade enhances the induction of long-term synaptic facilitation and long-term memory in Aplysia.

Tyrosine kinases have been implicated in cellular processes thought to underlie learning and memory. Here we show that tyrosine kinases play a direct role in long-term synaptic facilitation (LTF) and long-term memory (LTM) for sensitization in Aplysia. Tyrosine kinase activity is required for serotonin-induced LTF of sensorimotor (SN-MN) synapses, and enhancement of endogenous tyrosine kinase activity facilitates the induction of LTF. These effects are mediated, at least in part, through mitogen-activated protein kinase (MAPK) activation and are blocked by transcriptional and translational inhibitors. Moreover, brain-derived neurotrophic factor (BDNF) also enhances the induction of LTF in a MAPK-dependent fashion. Finally, activation of endogenous tyrosine kinases enhances the induction of long-term memory for sensitization, and this enhancement also requires MAPK activation. Thus, tyrosine kinases, acting through MAPK, play a pivotal role in LTF and LTM formation.

Animals↗
PubMed1999

Hematopoietic stem cell tracking in vivo: a comparison of short-term and long-term repopulating cells.

We have previously demonstrated that we could separate long-term repopulating stem cells from cells that provided radioprotection (short-term repopulating cells) on the basis of size and suggested that this might be due to the quiescent nature of long-term repopulating cells. To further define the activity of these populations, we used a dye (PKH26), which incorporates into the membrane of cells and is equally distributed to daughter cells when they divide. We developed an assay, which allowed us to retrieve PKH26(+) long-term and short-term repopulating cells in the hematopoietic tissues of the recipients posttransplant. We were able to recover the labeled cells and determine their cell cycle activity, as well as their ability to reconstitute secondary lethally irradiated hosts in limiting dilution. The results of our assay suggest that long-term repopulating cells are quiescent in the bone marrow (BM) 48 hours after transplant. We were able to detect only a few labeled cells in the peripheral blood posttransplant and even though cells homed to both the spleen and BM, more long-term repopulating cells homed to the marrow and only these cells, which homed to the marrow, were capable of reconstituting lethally irradiated secondary hosts long-term.

Animals↗
PubMed2001

[Short-term versus long-term antimicrobial prophylaxis in abdominal surgery: a multicenter open randomized comparative trial].

OBJECTIVE: To evaluate the outcome of short-term antimicrobial prophylaxis versus long-term in surgical site infection (SSI). METHODS: 731 patients undergoing abdominal operation from 15 hospitals were randomly divided into 2 groups. 358 patients were enrolled in the short-term group (24 h), and 373 patients in the long-term group (72 h). There was no difference between the 2 groups with regard to age, sex, and types operation. Netilmicin was used alone or in combination with metronidazole. RESULTS: The rates of SSI in the short-term and long-term groups were 0.84% and 2.68% (P > 0.05), respectively. CONCLUSIONS: The results demonstrated that the short-term antimicrobial agents prophylaxis is effective in the prevention of post-operative SSI. The long-term one act does not better than the short-term in terms of rationality and pharmacoeconomics.

Abdomen↗
PubMed2002

Noninvasive assessment of coronary microcirculatory function in postmenopausal women and effects of short-term and long-term estrogen administration.

BACKGROUND: Estrogen improves endothelial function in the coronary conduit vessels of animals; however, its effects on the coronary microcirculation have not been studied completely in humans. METHODS AND RESULTS: We measured myocardial blood flow (MBF) with a PET scan at rest, during cold pressor testing (CPT), and during dipyridamole hyperemia in 54 postmenopausal women without coronary artery disease. Of these, 23 were not and 31 women were taking long-term hormone replacement therapy (HRT) using estrogen either alone or with a progestogen. Each group was subdivided by coronary risk factors (RFs). Twelve young healthy women served as controls. In women not taking HRT, MBF measurements were repeated after 25 mg of conjugated equine estrogens IV. Neither short estrogen nor long-term HRT affected MBF at rest in women with and without RFs. Dipyridamole MBF was attenuated only in the women with RF who were not taking HRT. Short-term estrogen and long-term HRT did not reverse the abnormal response. MBF responses to CPT were abnormal in women not taking HRT, regardless of RFs (20+/-15% versus 32+/-21%) and remained unchanged after short-term estrogen administration. Long-term HRT normalized the response to CPT only in women without RF (53+/-22% versus 59+/-36% in the young women; NS). MBFs were similar for women on estrogen alone or estrogen plus a progestogen, regardless of presence or absence of RFs. CONCLUSION: Menopause is associated with abnormal CPT (an indirect measure of endothelial function), which can be reversed by long-term HRT only when RFs are absent. Progestogens do not antagonize this effect. Long-term HRT may therefore be useful in the primary prevention of coronary artery disease in women without RFs.

Adult↗
PubMed2006

Short-term and long-term mortality in very elderly patients admitted to an intensive care unit.

OBJECTIVE: To report short-term and long-term mortality of very elderly ICU patients and to determine independent risk factors for short-term and long-term mortality DESIGN AND SETTING: Retrospective cohort study in the medical/surgical ICU of a tertiary university teaching hospital. PATIENTS: 578 consecutive ICU patients aged 80 years or older. RESULTS: Demographic, physiological, and laboratory values derived from the first 24h after ICU admission. ICU mortality of unplanned surgical (34.0%) and medical patients (37.7%) was higher than that of planned surgical patients (10.6%), as was post-ICU hospital mortality (26.5% and 29.7% vs. 4.4%). Mortality 12 months after hospital discharge, including ICU and hospital mortality, was 62.1% in unplanned surgical and 69.2% in medical patients vs. 21.6% in planned patients. Only median survival of planned surgical patients did not differ from survival in the age- and gender-matched general population. Independent risk factors for ICU mortality were lower Glasgow Coma Scale score, higher SAPS II score, the lowest urine output over 8 h, abnormal body temperature, low plasma bicarbonate levels, and higher oxygen fraction of inspired air. High urea concentrations and admission type were risk factors for hospital mortality, and high creatinine concentration was an independent risk factor for 12-month mortality. CONCLUSION: Mortality in very elderly patients after unplanned surgical or medical ICU admission is higher than after planned admission. The most important factors independently associated with ICU mortality were related to the severity of illness at admission. Long-term mortality was associated with renal function.

Aged↗
PubMed2002

[Comparison of short-term and long-term results after aortocoronary bypass in ischemic heart disease in diabetics and non-diabetics].

In the presented study we have evaluated short-term and long-term results of the multiple aortocoronary bypass surgery in the patients with ischemic heart disease. We have compared the incidence of the preoperative and postoperative complications, short-term and long-term mortality in the group of diabetics in comparison to nondiabetics as well as the entry characteristics of both groups. Among 2518 patients who were treated with aortocoronary bypass surgery there were 773 (30.6%) diabetics. The diabetic patients were significantly elder, we have found more women among them, more frequent presence of hypertension, chronic heart failure and peripheral vascular disease. Contrary in the incidence of the previous myocardial infarction we have not found any significant difference between both groups. The patients with diabetes mellitus had lower ejection fraction of the left ventricle and significantly more extensive coronary artery disease which explains that in this group of patients the number of coronary bypasses was significantly higher. Comparing the incidence of preoperative complications we have not seen any significant difference between the patients with and without diabetes mellitus. Out of the postoperative complications we have noticed significantly more renal failure, infectious complications, low cardiac output syndrome and bleeding disorders in the diabetic patients. The duration of hospitalisation in the intensive care unit was significantly longer in diabetics (55.11 +/- 89.09 hours to 47.84 +/- 65.18 hours in nondiabetics, p < 0.05). 30 days mortality in diabetics was 3.75% and 2.4% in nondiabetics (p < 0.05). This difference was mainly due to the significantly higher incidence of multiorgans failure as a cause of death among diabetics (1.3% in diabetics, 0.5% in nondiabetics, p < 0.05). 89.1% of nondiabetics and 86.9% of diabetics lived 2-6 years after aortocoronary bypass surgery (n.s.). We have found the significantly higher long-term cardiovascular mortality (2-6 years) in diabetics (10.3%) then in nondiabetics (7.6%, p < 0.05).

Coronary Artery Bypass↗
PubMed1991

Comparative efficacy of short-term versus long-term cefoxitin prophylaxis against postoperative infection after radical hysterectomy: a prospective study.

We report the results of a randomized, double-blind comparison of short-term versus long-term cefoxitin prophylaxis against infections after radical abdominal hysterectomy with pelvic and para-aortic lymphadenectomy. Of 113 evaluable patients, 54 (47.8%) received short-term (three doses) and 59 (52.2%) long-term (12 doses) prophylaxis with intravenous cefoxitin (2 g per dose). No significant differences in demographics, preoperative risk factors, or clinical course were detected between the two groups; nor did we detect significant differences in the incidence of surgical-site-related infections (7.4 versus 5.1%, respectively, P = .61), postoperative urinary tract infection, or other febrile morbidity. We conclude that short-term and long-term cefoxitin prophylaxis are equally effective for the prevention of post-operative surgical-site-related infections after radical hysterectomy.

Adult↗
PubMed2003

Different phosphatase-dependent mechanisms mediate long-term depression and depotentiation of long-term potentiation in mouse hippocampal CA1 area.

Two types of synaptic depression have been described in the hippocampus, long-term depression and depotentiation of long-term potentiation known to recruit the serine/threonine protein phosphatases PP1, PP2A and PP2B (calcineurin). The contribution of each of these protein phosphatases is controversial. To examine the role of the Ca2+/calmodulin-dependent protein phosphatase calcineurin in long-term depression and depotentiation, we analysed the effect of genetically inhibiting calcineurin reversibly in the hippocampus, using the doxycycline-dependent rtTA system in transgenic mice. We show that reducing calcineurin activity has no effect on long-term depression but reversibly affects depotentiation. Consistently, the calcineurin inhibitor FK-506 reproduces the depotentiation impairment observed in the mutant mice but does not affect long-term depression in control animals. In contrast, the PP1/PP2A inhibitor okadaic acid fully blocks both long-term depression and depotentiation. These data demonstrate that the nature of signalling cascades induced by synaptic activity depends on the initial synaptic state. While depression of potentiated synaptic responses requires activation of PP1/PP2A and/or calcineurin, depression of basal synaptic responses depends only on PP1/PP2A activation.

Animals↗
PubMed1995

Transient protein kinase C activation primes long-term depression and suppresses long-term potentiation of synaptic transmission in hippocampus.

Activity-dependent long-lasting plasticity in hippocampus and neocortex includes long-term potentiation (LTP) and long-term depression (LTD) of synaptic strength. Recent studies have confirmed theoretical predictions that the sensitivity of LTP- and LTD-inducing mechanisms is dynamically regulated by previous synaptic history. In particular, prior induction of either repeated short-term potentiations or LTP lowers the threshold for induction of LTD and raises the threshold for LTP. In the current study, transient activation of protein kinase C with phorbol 12,13-diacetate was able to substitute for synaptic activity in priming synapses to exhibit enhanced homosynaptic LTD and to suppress the induction of LTP at Schaffer collateral synapses in area CA1 of hippocampal slices. This priming lasted 30 min, but not 3 hr, following phorbol 12,13-diacetate bath application. These data suggest that a protein kinase C-sensitive phosphorylation site may be an activity-sensitive target mediating the rapid expression of LTP and LTD.

Animals↗