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The rate of enrichment of the Tula region flora with adventive species was quantitatively estimated taking into account the changes of their degree of naturalization during the last 200 years. Numerical score of degree of the naturalization for each species was used to compile the initial database: "0", species absent from the territory; "1", ephemerophyte; "2", colonophyte; "3", epecophyte; "4", argiophyte; "?", lack of data. Non-interpolated integral index of the dynamics of adventive flora NI(t) was calculated from this database. This index displays the sum of the degrees of naturalization of all the adventive species in the flora in some particular year. The interpolation of the initial database, aimed at minimizing the influence of random factors (e.g., gaps in observations or different activity of the researchers in different years), was performed by substituting the "?" symbol by a series of intermediate values based on studies of the data for adjacent territories. Interpolated integral indices I(t) were calculated from the interpolated database. These indices were then leveled out with Morlet wavelets, in order to distinguish random spikes (lasting less than 50 years) from the analyzed signal, and thus approximate the index dynamics to the objective trend that represents the dynamics of the flora and not the rate of activity of the researchers. The dynamics of the adventive flora of the Tula region revealed with this method shows the following facts: 1) average rate of the enrichment of the adventive flora with strange species has been constant for these 200 years and amounted to 15 species per decade; 2) average rate of naturalization was relatively low and constant, amounting to 5 species per decade; 3) fluctuations of the composition and naturalization degree of the Tula region adventive flora species were not shown to be dependant directly on the changes in the territory's economic development during the last two centuries; 4) no periodicity was recorded in the advent of new species, and the fluctuations of the number of adventive species can be attributed to the fluctuations of research intensity.
The incidence rates of opportunistic diseases, hospital admission and death have fallen markedly since the advent of highly active antiretroviral therapy (HAART). We examined the impact of HAART on the pattern of HIV-related respiratory diseases necessitating hospitalization. We retrospectively compared the numbers and etiologies of respiratory diseases diagnosed in HIV-infected patients hospitalized in the chest department of a Paris university hospital during the three years preceding widespread prescription of HAART in France (era 1, starting in July 1993) and the first three years of widespread HAART prescription (era 2, starting in July 1996). Respectively, 207 and 119 HIV-infected patients were admitted for respiratory disease in era 1 and era 2. Only 31.1% of patients admitted during era 2 were receiving HAART. Pulmonary opportunistic infections other than Pneumocystis carinii pneumonia (PCP) (p = 0.0008) and exacerbations of chronic bronchial disease due to gram-negative bacilli (p = 0.04) virtually disappeared in era 2. In contrast, PCP, bacterial pneumonia, tuberculosis, pulmonary Kaposi's sarcoma and pulmonary non-Hodgkin lymphoma showed only a twofold decrease in era 2, while lung cancer was more frequent (p = 0.004). The frequency of severe respiratory diseases necessitating hospitalization of HIV-infected patients has fallen since the advent of HAART, and their etiologic distribution has changed.
Clinical trials of beta blockers in heart failure have generally required that patients be receiving optimal drug therapy before randomization to the study medication. Therefore, because beta blockers are used in addition to conventional drug therapy, review of the standard drug therapy of mild-to-moderate heart failure before the advent of beta blockade is essential to understanding the role of beta blockers in the treatment of heart failure. The conventional medical management of systolic heart failure includes angiotensin-converting enzyme (ACE) inhibitors, which should be used as first-line therapy; diuretics, for the management of body fluid-volume excess; digoxin; and some other vasodilators. These therapies have been evaluated in large-scale, randomized, controlled trials. ACE inhibitors have been shown to significantly attenuate disease progression and improve outcome (ie, morbidity and mortality) in patients with mild-to-moderate systolic heart failure. Controversial or unproven therapies include nonglycoside inotropic agents, angiotensin II receptor antagonists, antiarrhythmic agents, anticoagulants, and calcium channel blockers. The pharmacologic management of diastolic heart failure is largely empirical and is directed at reducing symptoms. Symptoms caused by increased ventricular filling pressures may be treated with diuretics and long-acting nitrates. Some calcium channel blockers and most beta blockers prolong diastolic filling time by slowing heart rate, thereby potentially improving the symptoms of diastolic heart failure. Calcium antagonists, beta blockers, diuretics, and ACE inhibitors may also promote regression of left ventricular hypertrophy and thus improve ventricular compliance, possibly preventing the development of diastolic dysfunction. Because randomized controlled trials of diastolic heart failure are lacking, this review focuses on the conventional management of mild-to-moderate systolic heart failure before the advent of beta blockade.
BACKGROUND: The advent of videothoracoscopy may restrict the indications for thoracotomy in blunt chest trauma. METHODS: We retrospectively compared two groups of patients with blunt chest trauma observed in consecutive periods, before and after the advent of videothoracoscopy, 989 patients from 1989 to 1993 and 908 patients from 1994 to 1998. RESULTS: During the first period, 38 thoracotomies were performed; but in 8 instances (21%), no major injuries were found. In the second period, 36 videothoracoscopies were performed to repair the lung (n = 5) or diaphragm (n = 5), to evacuate clots (n = 4), pericardial effusion (n = 3), and empyema (n = 2). Six procedures were converted and 11 findings were negative for lesions. Only nine intentional thoracotomies were performed, and significant lesions were found in each case. CONCLUSION: Videothoracoscopy has reduced the number of thoracotomies performed. Thoracotomy can be limited to massive bleeding with hemodynamic instability, major air leak, radiologic evidence of mediastinal enlargement or diaphragmatic rupture, or major anterolateral flail chest.
Changes in female sexual behaviour with the advent of AIDS and safer sex campaigns were studied. Subjects were drawn from a wide social spectrum of women attending an STD clinic in West London where there is a high prevalence of HIV infection among homosexual men. Between 1982 and 1989, 4224 women answered a self-administered questionnaire: women who reported more than one sexual partner in the previous year fell from 56.9% in 1982 to 51.8% in 1989 (p = 0.003). Anal intercourse showed no change and was reported by 8.8% in 1982 and 9.4% in 1989 (p = 0.8). Oral intercourse increased from 36.9% in 1982 to 44.7% in 1989 (p = 0.001). Condom use for contraception increased from 3.6% in 1982 to 16.2% in 1989 (p less than 0.001). Between 1987 and 1989, 35.6% of 3199 women reported having non-regular partners with no significant trend over this period; these women had earlier coitarche (17.0 years cf 17.9 years), many more partners (p less than 0.0001) and more practised anal (p = 0.007) and oral (p less than 0.0001) intercourse. However, frequent use of condoms doubled from 23.6% in 1987 to 47.6% in 1989. During this period, the prevalence of antibody to HIV (anti-HIV) remained unchanged (0.27-0.37%), but more women declined to be tested. Anonymised testing showed that none of those who refused consent for named testing was anti-HIV positive. It is concluded that significant changes in female sexual behaviour have taken place with the advent of AIDS but there has been no evidence of heterosexual spread beyond the confines of well defined risk behaviours. Risks of the magnitude reported in homosexual men were not found in heterosexual women.
BACKGROUND/AIMS: To define whether bacterial translocation occurs over the course of acute edematous pancreatitis and to correlate its presence to the advent of an infection since data in humans are lacking. METHODS: Thirty-three patients hospitalized over the period January 2000-January 2001 were subjected to venipuncture at regular time intervals for the collection of blood samples for blood culture and for determination of endotoxins and of C-reactive protein. Endotoxins were measured by the Limulus assay and C-reactive protein by nephelometry. RESULTS: A wide range of concentrations of endotoxins was observed over the first 3 days of the disease. Mean (+/-SE) of endotoxins was 4.01 +/- 1.36 and 2.42 +/- 0.95 EU/ml 3 and 6 h, respectively, after admission of afebrile patients. Respective values 3 and 6 h after admission of febrile patients were 3.03 +/- 1.14 and 5.84 +/- 2.28 EU/ml (normal <0.1 EU/ml); these values gradually decreased after the second day. No correlation was found between endotoxins and C-reactive protein. Endotoxins were increased as a result of the occurrence of an infection on the third day. CONCLUSIONS: A significant level of endotoxemia is observed over the course of acute edematous pancreatitis, which might be correlated to the advent of the systemic inflammatory response.
CONTEXT: Since the advent of highly active antiretroviral therapy (HAART) in 1996, the incidence of HIV-especially among young men who have sex with men-and the prevalence of unprotected sex among HIV-positive persons have increased. The characteristics associated with unprotected sex among youth living with HIV since the advent of HAART have not been explored. METHODS: Samples of HIV-positive youth aged 13-24 were taken from two intervention studies that targeted the sexual behaviors of HIV-positive youth-one from 1994 to 1996 (pre-HAART) and the other from 1999 to 2000 (post-HAART). Generalized estimating equations were used to identify characteristics associated with unprotected sex in each sample. RESULTS: The prevalence of unprotected sex in the post-HAART sample was more than twice that in the pre-HAART sample (62% vs. 25%). Among the pre-HAART sample, being a man who has sex with men and having sex with a casual partner were negatively associated with the odds of unprotected intercourse (odds ratios, 0.5 and 0.2, respectively). Among the post-HAART sample, unprotected sex was negatively associated with knowing that a partner was HIV-negative (0.2) and positively associated with poorer mental health (1.02). In analyses among the post-HAART sample, poorer mental health was associated with increased odds of unprotected sex among youth living with HIV who were not receiving the treatment (1.02). CONCLUSIONS: Interventions for HIV-positive youth must be designed to address the complex needs of those youth who simultaneously suffer from HIV and poor mental health.
BACKGROUND: The majority of patients with breast carcinoma with > or = 10 metastatic axillary lymph nodes (ALNs) develop recurrent disease within 5 years from diagnosis. The purpose of the current study, performed retrospectively, was to characterize the natural history of this subset of patients, both before and after the advent of adjuvant anthracycline-based chemotherapy and tamoxifen. METHODS: Retrospectively, patients with primary breast carcinoma (N = 882) with > or = 10 metastatic ALNs, treated between 1954 and 1998, were selected from 3 institutions: The University of Texas M. D. Anderson Cancer Center (Houston, TX); the Institut Gustave Roussy (Villejuif, France); and Hospital Clinico Universitario (Valencia, Spain). All patient data had been registered prospectively in clinical databases. One group consisted of 314 patients treated with locoregional therapy alone (no adjuvant therapy) from 1954 to 1983. The second group included 568 patients who received adjuvant anthracycline-based chemotherapy between 1974 and 1998 with or without adjuvant tamoxifen. RESULTS: The median follow-up time was 140 months. Disease-free survival rates at 15 and 20 years for the no adjuvant therapy and adjuvant therapy groups were 17% and 16% versus 26% and 24%, respectively. The overall survival rates at 20 years for the no adjuvant therapy and the adjuvant therapy groups were 9% and 21%, respectively. By multivariate analysis, the independent factors associated with survival in the adjuvant therapy group were tumor size and the number of metastatic lymph nodes. CONCLUSIONS: The retrospective analysis suggested that adjuvant anthracycline-based chemotherapy and hormonal therapy have altered the natural history in this high-risk group of patients. However, despite such improvements, survival rates remained low, and innovative therapeutic approaches are, therefore, needed to improve clinical outcomes.
This is a review of 1,000 consecutive cases of severe head injury admitted to our Neurosurgical Department between January 1973 and August 1976, before the advent of CT scanning. All patients were comatose following head injury (GCS less than or equal to 8) and were treated homogeneously by the same neurosurgical team by a protocol that included immediate resuscitation on arrival, diagnosis of intracranial lesions by angiography, early surgery when needed, mechanical ventilation, steroids, and mannitol. Extracranial lesions, even if preponderant, were treated by various specialists in the Neurosurgical Department, which for all practical purposes operated as an Emergency Department. Admission criteria were very broad with no preadmission selection. The overall mortality for this series was 45%. A little less than half the patients made good recoveries or remained moderately disabled (47%); 6% were severely disabled, and 2% survived in a persistent vegetative state. More than two-thirds of the patients were brought to our Neurosurgical Department after a short stay at a general hospital; 72% were admitted within 6 hours of injury; 71% were traffic accident victims; and 34% had significant associated extracranial injuries. Carotid angiography was performed in 78% of the patients and indicated the presence of an intracranial haematoma requiring surgery in 36% of the whole series. Mortality was significantly higher in operated than in unoperated patients (56% versus 39%); those treated surgically, however, were older, in worse clinical condition, and showed a higher incidence of acute subdural haematomas associated with brain contusion. Carotid angiography proved very effective in revealing the presence of an expansive lesion but failed to reflect the severity of brain damage, since the group with "negative" angiograms showed a high mortality (52%). Patients with a lucid interval had a higher percentage of surgical lesions than those with immediate coma (58% versus 26%); but fully 42% of them did not require surgery, and 25% had negative angiograms. From the prognostic point of view the clinical data elicited after initial resuscitation were highly predictive of the outcome: some individual neurological signs, such as mydriasis, posturing and eye movements, were not inferior to the GCS score in that respect. Age also proved a strong predictor, since elderly patients are more likely to have severe subdural and parenchymal lesions and their clinical severity is accordingly greater.(ABSTRACT TRUNCATED AT 400 WORDS)
This study aims to investigate the influence of human immunodeficiency virus (HIV) infection on the neurodegenerative processes normally associated with ageing. We have looked for evidence of beta amyloid and hyperphosphorylated Tau deposition in HIV-infected subjects before and after the advent of highly active anti-retroviral therapy (HAART). In addition we have looked for evidence of axonal damage. We have compared these HIV-positive cases with age-matched controls and with older non-demented controls. We find no evidence of significant premature beta amyloid deposition in HIV-infected cases; however, we do observe elevated levels of hyperphosphorylated Tau in the hippocampus of many HIV-infected subjects, compared with age-matched controls. The greatest levels of hyperphosphorylated Tau are noted in HAART-treated subjects. Axonal damage marked by expression of beta amyloid pre-cursor protein (BAPP) was highly variable in all groups including control subjects. We surmise that HIV infection and/or the use of anti-retroviral therapy may predispose to accelerated neuroageing in the form of hyperphosphorylated Tau deposition in the hippocampus. Within the age groups studied these significant neuropathological changes remained subclinical and were not yet associated with cognitive impairment.
The advent of surgical gloves had a double evolution. Evolution of the material: cecum of a sheep, cotton, silk, leather, rubber. Originally introduced to protect theatre staff's hands from corrosive solutions, subsequent use was to protect the patient from contamination by theatre staff. Many surgeons contributed to the evolution of the surgical gloves. The use of gloves was truly part of an evolutionary process than a discovery. The turning of surgical gloves is now incontestable, and their use more and more important. Surgical gloves must secure a crossing protections between surgeon and patient.
The development of clinically based written standards to reduce the frequency and severity of medical malpractice loss appears to be gaining in popularity among provider specialty groups and professional liability underwriters. To date, such standards have addressed problems in specialties such as obstetrics and anesthesia where dollar losses associated with malpractice claims have been high. Guidelines can be developed and used by providers on a purely voluntary basis or mandated on an involuntary basis by third parties such as malpractice insurance companies or legislators. Because the advent of risk-control standards is a relatively new phenomenon, formal scientific studies on the long-term benefits of such guidelines have not yet been published. However, it appears that sharp reductions of malpractice losses in specialties such as anesthesia have coincided with the implementation of formal written standards specifically designed for liability control. This has led some liability insurance carriers to decrease premiums associated with specialists following such standards. Many providers are understandably concerned about the potential use of written standards by plaintiff attorneys in medical malpractice suits. Although it is possible that such policies and guidelines could be admitted into evidence to show that a provider breached the legal duty or standard of care owed to a patient, it is uncertain whether these risk-control standards could ultimately pass the evidentiary rules of relevancy or materiality in a given lawsuit. It is clear, however, that the consensus-based process of creating clinical standards and guidelines specifically for controlling professional liability losses is itself a powerful and emerging standard for health care risk management programs.
In 1987 an assessment of mottling in incisor teeth was carried out on a random sample of 12-year-old children in Liverpool, England. The number of children examined was 471. All of these children were born and had lived in Liverpool when the fluoride content of the water supply had averaged 0.1 parts/10(6). During this time the market share of fluoride toothpastes had increased from 5% in the early 1970s to 91.8% in 1987. The mouth prevalence of mottling was found to be 31.1%. The tooth prevalence of mottling was found to be 7.83%. There was no sex difference. The data obtained was compared with findings in 1974-75 in Liverpool before the advent of fluoride toothpastes. The data suggests that there has been a decrease in the prevalence of mottling in Liverpool since 1974-75.
In Prehistoric and Mediaeval times few dentitions in this country remained intact much after the age of 40-45 years. The point is made that dental caries and periodontal disease played little part in this early disintegration and it is unlikely that the population of this time suffered severely with their teeth. A change in dietary habits in the late seventeenth and early eighteenth century measurably increased the lifespan of the dentition, but also radically altered the prevalence of caries. This change is likely to have been responsible for a vast increase in dentally-related pain and suffering which was only capable of being tackled as a social problem by the advent of modern dentistry.
1. A study was undertaken of the conditions that might operate in the synthesis and hydrolysis of arginine by axolotl liver homogenate to test a previous postulate that liver arginase of the non-metamorphosed Mexican axolotl is not able to hydrolyse arginine formed from citrulline and aspartic acid, though it can split exogenous arginine, and also that an enhanced capacity to hydrolyse endogenous arginine plays a major role in the advent of ureotelism observed during the metamorphosis of the axolotl. 2. It was found that the arginase from axolotl liver is very unstable under the conditions followed, contrary to what is observed in rat liver. 3. Axolotl arginase is able to hydrolyse endogenous arginine if preserved. 4. Mn(2+) protects the enzyme and renders it able to split endogenous arginine. 5. It is suggested that the metal ion produces a change of conformation of the enzyme that, being stable, is capable of hydrolysing the amino acid, or that the new conformation is appropriate for interaction with the sites of arginine synthesis.
Capsule endoscopy is a new, wireless, endoscopic examination of the small intestine. To date, two small clinical trials have been reported utilizing capsule endoscopy in patients with obscure gastrointestinal bleeding, and have shown its superiority to push enteroscopy in diagnosing the cause of blood loss. No outcome studies have been reported. This paper proposes a change in practice guidelines for obscure bleeding. It is our opinion that, in the future, with the advent of wireless capsule endoscopy, the evaluation of patients with obscure gastrointestinal bleeding will be very different from the practice of medicine today. We believe that capsule endoscopy will become the first-line method for the evaluation of patients with obscure bleeding, once upper endoscopy and colonoscopy have been shown to be negative. In patients with active bleeding, capsule endoscopy will confirm the small bowel as the site of bleeding, providing a location, or, if the study is negative for the small intestine, may indicate that the bleeding is either colonic or gastric in origin. In a patient with active bleeding within the small intestine, the capsule will guide further evaluation and therapy. A patient with a small bowel tumour detected by capsule endoscopy will proceed directly to laparoscopic surgery. If the site of bleeding is identified in the proximal small bowel and there is no mass, push enteroscopy will be used to re-identify the site and cauterize it. A distal small bowel site will require surgical intervention, coupled with intra-operative enteroscopy. Should the patient be too sick to undergo surgery, medical therapy utilizing hormonal agents will be considered. A colonic site will be evaluated by colonoscopy. In patients with a more occult or intermittent type of bleeding and in those whose upper endoscopies and colonoscopies are negative, capsule endoscopy will be used similarly to identify a bleeding lesion and thereby direct subsequent testing or treatment.
Gaucher disease, the most prevalent lysosomal storage disorder, is characterized by hepatosplenomegaly, hypersplenism, and rarely, neurological involvement. The most variable symptoms relate to skeletal disease, and both onset and progression are difficult to predict on the basis of genotype. This review describes findings from a large referral clinic (> 500 patients) and from the literature in the decade since the advent of specific enzyme replacement therapy. Such therapy is effective in reducing visceral and hematological involvement, but its greatest advantage as regards the skeleton is prevention of irreversible damage. Avascular necrosis of the joints-particularly the hips but also the knees and shoulders-and pathological fractures of the long bones including the ribs, as well as episodic "crises' of bone pain in children and young adults, are common manifestations. Various imaging modalities should be performed at baseline for life-long monitoring, and then as required because of specific complaints. Surgical interventions such as joint arthroplasties are important adjuvant treatments in this population; presurgical hematological profiling plus antibiotic cover and postoperative pain control are equally critical. Opportunities for orthopedic consultations with senior surgeons are not abused by our patients. These reflect disease-related morbidity, with greater numbers of requests being made by patients requiring enzyme therapy, who by definition have more severe disease characteristics.