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PubMed2006

Soil-plant hydrology of indigenous and exotic trees in an Ethiopian montane forest.

Fast-growing exotic trees are widely planted in the tropics to counteract deforestation; however, their patterns of water use could be detrimental to overall ecosystem productivity through their impact on ecosystem water budget. In a comparative field study on seasonal soil-plant water dynamics of two exotic species (Cupressus lusitanica Mill. and Eucalyptus globulus Labill.) and the indigenous Podocarpus falcatus (Thunb.) Mirb. in south Ethiopia, we combined a 2.5-year record for climate and soil water availability, natural-abundance oxygen isotope ratios (delta(18)O) of soil and xylem water, destructive root sampling and transpiration measurements. Soil was generally driest under C. lusitanica with its dense canopy and shallow root system, particularly following a relatively low-rainfall wet season, with the wettest soil under E. globulus. Wet season transpiration of C. lusitanica was twice that of the other species. In the dry season, P. falcatus and C. lusitanica reduced transpiration by a factor of six and two, respectively, whereas E. globulus showed a fivefold increase. In all species, there was a shift in water uptake to deeper soil layers as the dry season progressed, accompanied by relocation of live fine root biomass (LFR) of C. lusitanica and P. falcatus to deeper layers. Under P. falcatus, variability in soil matric potential, narrow delta(18)O depth gradients and high LFR indicated fast water redistribution. Subsoil water uptake was important only for E. globulus, which had low topsoil LFR and tap roots exploiting deep water. Although P. falcatus appeared better adapted to varying soil water availability than the exotic species, both conifers decreased growth substantially during dry weather. Growth of E. globulus was largely independent of topsoil water content, giving it the potential to cause substantial dry-season groundwater depletion.

Biological Transport↗

PubMed2001

Umbilical reconstruction in patients with exstrophy: the kangaroo pouch technique.

PURPOSE: Before the current attitude of umbilical preservation and transposition at bladder closure in patients with exstrophy the navel was systematically removed. Many patients without an umbilicus complain about this deformity. We report a simple technique of umbilical reconstruction using a rectangular skin flap fashioned as a kangaroo pouch. MATERIALS AND METHODS: Four patients 10 to 20 years old with exstrophy underwent this procedure. A small cutaneous pouch was fashioned by folding a vertical rectangular skin flap and the pouch was anchored deeply to the rectus fascia. A compressive dressing was packed into the new umbilicus and left in place for several days. RESULTS: The 4 patients have an excellent cosmetic result with adequate location, good morphology and sufficient depth at a mean followup of 8 months (range 6 to 11). CONCLUSIONS: Our technique of umbilical reconstruction is easy to perform and provides good mid-term cosmetic results. This technique is particularly adapted for patients with exstrophy who often require external genital reconstruction at the same time.

Adolescent↗

PubMed2004

Clinical outcomes following treatment of human intrabony defects with GTR/bone replacement material or access flap alone. A multicenter randomized controlled clinical trial.

AIM: This prospective multicenter randomized controlled clinical trial was designed to compare the clinical outcomes of papilla preservation flap surgery with or without the application of a guided tissue regeneration (GTR)/bone replacement material. MATERIALS AND METHODS: One hundred and twenty-four patients with advanced chronic periodontitis were recruited in 10 centers in seven countries. All patients had at least one intrabony defect of > or = 3 mm. The surgical procedures included access for root instrumentation using either the simplified or the modified papilla preservation flap in order to obtain optimal tissue adaptation and primary closure. After debridement, the regenerative material was applied in the test subjects, and omitted in the controls. At baseline and 1 year following the interventions, clinical attachment levels (CALs), probing pocket depths (PPDs), recession, full-mouth plaque scores and full-mouth bleeding scores (FMBS) were assessed. RESULTS: One year after treatment, the test defects gained 3.3 +/- 1.7 mm of CAL, while the control defects yielded a significantly lower CAL gain of 2.5 +/- 1.5 mm. Pocket reduction was also significantly higher in the test group (3.7 +/- 1.8 mm) when compared with the controls (3.2 +/- 1.5 mm). A multivariate analysis indicated that the treatment, the clinical centers, baseline PPD and baseline FMBS significantly influenced CAL gains. Odds ratios (ORs) of achieving above-median CAL gains were significantly improved by the test procedure (OR = 2.6, 95% CI 1.2-5.4) and by starting with deeper PPD (OR = 1.7, 1.3-2.2) but were decreased by receiving treatment at the worst-performing clinical center (OR = 0.9, 0.76-0.99). CONCLUSIONS: The results of this trial indicated that regenerative periodontal surgery with a GTR/bone replacement material offers an additional benefit in terms of CAL gains, PPD reductions and predictability of outcomes with respect to papilla preservation flaps alone.

Alveolar Bone Loss↗

PubMed1990

Clinical evaluation of a biodegradable collagen membrane in guided tissue regeneration.

A bio-resorbable type I collagen membrane was investigated as a barrier for guided tissue regeneration. Ten human subjects with at least one pair of contralateral periodontal lesions with probing pocket depths of greater than or equal to 5 mm and radiographic evidence of greater than or equal to 40% bone loss were included. Each patient underwent contralateral surgical flap procedures. A collagen barrier was adapted to the tooth in the experimental defect and the flap replaced and sutured. The controls consisted of the same procedure without the placement of the barrier. Standardized measurements of change in probing attachment levels and fill of intrabony defects were obtained at the time of surgery and 1 year later at the time of surgical re-entry. The differences in change of probing attachment levels and amount of bone fill between individual test and control sites were compared utilizing the student's t-test for paired samples. The mean probing attachment gain in the test sites was 0.56 +/- 0.57 mm, and there was a mean probing attachment loss of 0.71 +/- 0.91 mm in the control sites (P less than 0.01). The gain of bone in test lesions was 1.16 +/- 0.95 mm, while no gain was observed in the control lesions (P less than 0.01). The results of this study demonstrated that sites treated with a collagen barrier comprised of cross-linked bovine Type I collagen exhibited significantly better healing as compared to control sites over the 1-year period of the study.

Adult↗

PubMed2005

[Alternatives to the radiotherapy of stage I testicular seminoma].

Adjuvant irradiation is currently the most frequently used standard treatment for the clinical stage I seminoma (CSI) following orchiectomy. There is a potential carcinogenic risk with irradiation that prompted a search for alternative adjuvant treatment approach. The cure in CSI seminoma patients can be achieved with surveillance or chemotherapy. Surveillance takes into account the fact that 80% of patients do not need any adjuvant treatment after orchiectomy and are overtreated by adjuvant irradiation. Recently, one cycle of adjuvant carboplatin has been proven in a prospective randomized trial. Taken together, all three treatment options are acceptable standard strategies for the management of patients with CSI. Finally, the experience with surveillance strategy allowed an in-depth meta analysis of factors predictive for relapse discrimining the patients who are in need of post orchiectomy adjuvant treatment from those who safety can be followed by the surveillance strategy. However, this risk adapted approach is still under prospective evaluation.

Chemotherapy, Adjuvant↗

PubMed1981

[Structural and functional alterations of the mucosa of a jejunal segment, interposed isoperistaltically after total gastrectomy according to Longmire-Gütgeman (author's transl)].

Six patients had total gastrectomy because of carcinoma followed by jejunum isoperistaltic interposition according to Longmire. A jejunal biopsy was taken in every case during operation and three and six months later endoscopically for morphometric and functional evaluation of small bowel mucosa. Three months after the operation a rise of L-phenylalanin in vitro uptake, an increase in villus height, surface area and a deepening of the crypts with raised mitotic activity of the crypt cells was found. The ratio of villus height to crypt depth was increased, although not significantly. On the other hand the activity of sucrase was initially decreased. Six months postoperatively all parameters had become normal besides the disaccharidases. These changes may be due to adaptive mucosal hyperplasia after small bowel resection or to luminal mucosal damage followed by compensatory hyperregeneration. Finally a humoral stimulus for mucosal hyperplasia as a postoperative effect is discussed.

Biopsy↗

PubMed2004

Plasma GLP-2 levels and intestinal markers in the juvenile pig during intestinal adaptation: effects of different diet regimens.

Adaptation of the residual small bowel following resection is dependent on luminal and humoral factors. We aimed to establish if circulating levels of glucagon-like peptide (GLP-2) change under different dietary regimens following resection and to determine if there is a relationship between plasma GLP-2 levels and markers of intestinal adaptation. Four-week-old piglets underwent a 75% proximal small bowel resection (n = 31) or transection (n = 14). Postoperatively they received either pig chow (n = 14), nonpolymeric (elemental) infant formula (n = 7), or polymeric infant formula alone (n = 8) or supplemented either with fiber (n = 6) or with bovine colostrum protein concentrate (CPC; n = 10) for 8 weeks until sacrifice. Plasma GLP-2 levels were measured at weeks 0, 2, 4, and 8 postoperatively. In addition, end-stage parameters were studied at week 8 including weight gain, ileal villus height, crypt depth, and disaccharidase levels. Plasma GLP-2 levels were higher in resected animals compared to transected animals fed the same diet. Plasma GLP-2 levels were significantly increased in the colostrum protein isolate-supplemented animals following resection compared to all other diet groups. The increase in plasma GLP-2 (pM) was greatest in the first 2 weeks postresection (week 0, 15.5; week 2, 30.9), followed by a plateau at weeks 2 to 4 and a decrease in GLP-2 levels from week 4 to week 8. At week 8, no relationships were found between the plasma GLP-2 levels and the measurements of weight gain, villus height, lactase, sucrase, maltase, crypt depth, or villus/crypt ratio. Plasma GLP-2 levels increase in the first weeks following massive small intestinal resection. The increase in plasma GLP-2 levels was enhanced by supplementation of the diet with CPC. The changes in GLP-2 levels observed in this study may suggest that GLP-2 plays a role in the adaptive response in the intestine following resection in this preclinical model.

Adaptation, Physiological↗

PubMed1987

Adaptation to chronic illness. Analysis of nursing research.

The review of reported nursing research on chronic illness has many implications for nursing practice. Results of these studies may be implemented in many of the interventions provided for chronically ill patients. There needs to be collaboration between the researcher and practitioner to share knowledge of interventions that promote adaptation to chronic illness, and to investigate new and innovative therapies. Another contribution to nursing practice is the psychosocial variables that affect adaptation of chronically ill patients. Depending on the health problem and practice setting, nurses need to identify which variable may increase the effectiveness of their interventions and how they can best promote adaptation. Particularly noticeable was the absence of studies on the prevention of chronic illness. Although there is documented evidence of the relationship between stress and illness, and predictions that future environments will be even more stressful, a needed area for nursing research is prevention of chronic health problems. Areas such as stress management, health promotion, relaxation training, and behavior modification are timely subjects for nurses to research for prevention of these problems. There are merits to studying a particular chronic health problem in depth and in studying the commonalities among several chronic illnesses. With knowledge of both the physical and psychosocial, nurses are in an ideal position to contribute to the knowledge base of human responses to chronic illnesses.

Adaptation, Psychological↗

PubMed1993

Psychosocial issues in reproductive genetic testing and pregnancy loss.

This paper considers the psychosocial experience of women undergoing reproductive genetic testing, with attention to the impact of pregnancy loss after testing. New directions for research are called for to provide more in-depth understanding of the meaning of these experiences for women and their male partners.

Abortion, Eugenic↗

PubMed2000

Posttraumatic residues of captivity: a follow-up of Israeli ex-prisoners of war.

BACKGROUND: This article examines the long-term impact of wartime captivity. METHOD: One hundred sixty-four prisoners of war (POWs) and 189 matched combatants of the 1973 Yom Kippur War filled out a series of questionnaires that assessed posttraumatic stress disorder (PTSD), general psychiatric symptomatology, and social functioning according to DSM-III-R criteria. RESULTS: Almost 2 decades after the war, ex-POWs exhibited higher rates and greater intensity of posttraumatic stress reactions, more general psychiatric symptomatology, and more severe problems in functioning at home, at work, and in the military than did the control group (Israeli veterans who were not POWs). They were also more likely to obtain official disability recognition and to seek psychological help. Their recovery was slower and professional help less effective. In addition, the veterans with PTSD in both groups had high rates of comorbid general psychiatric symptomatology. CONCLUSION: These findings point to the depth, range, and persistence of the stress residuals of wartime captivity.

Adaptation, Psychological↗

PubMedDate not supplied

Somatostatin analogue predisposes enterocytes to apoptosis.

The somatostatin analogue octreotide impairs intestinal regeneration and the adaptive response to intestinal resection and other stimuli. These effects are mediated in part by inhibition of enterocyte migration and proliferation. The aim of this study was to determine whether octreotide promotes enterocyte apoptosis. Twenty-four New Zealand white rabbits were studied including 18 animals that underwent patch enteroplasty in the distal ileum to stimulate the mucosa and six unoperated controls. The patched animals either received 100 microgram or 1000 microgram of subcutaneous octreotide daily or served as operated control subjects. Normal ileal mucosa adjacent to the patch was evaluated at 7 days for villus height, crypt depth, crypt cell production rate (CCPR), and in situ end labeling of DNA fragmentation. Mean DNA fragmentation was significantly greater in octreotide-treated animals (P <0.05 Mann-Whitney rank test). Fragmentation scores ranged from 1.0 to 1.5 in controls and 1.1 to 2. 65 in treated animals. Staining of enterocytes was quite heterogenous, however, among the villi of individual treated animals. Staining was greater and cells with chromatin condensation were more prevalent near the tip of the villus. Octreotide increased apoptosis at the villus tip, lateral villus, and crypt. The two control groups had similar villus height, crypt depth, and CCPR The two octreotide-treated groups had similar villus height and CCPR compared to control animals. However, crypt depth was significantly less in the octreotide-treated animals (100 +/- 9 micrometer and 90 +/- 6 micrometer, 100 microgram, and 1000 microgram) compared to controls (121 +/- 10 micrometer and 117 +/- 10 micrometer, unoperated and operated; P <0.05). Crypt depth but not villus height correlated with DNA fragmentation. Neither correlated with CCPR. The following conclusions were reached: (1) Octreotide treatment is associated with increased DNA fragmentation in enterocytes; (2) octreotide promotes apoptosis in both villus and crypt compartments; (3) predisposition to apoptosis may play a role in octreotides effects on intestinal regeneration and adaptation; and (4) the role of proliferation and apoptosis in determining the size of the enterocyte compartments remains unclear.

Adaptation, Physiological↗

PubMed1984

Simple device for determining an index of echogenicity.

The technique reported here uses a simple electronic system adaptable to a standard manual echograph with the aim of obtaining a numerical index of echogenicity. The index is the ratio of the average echo amplitude within a gated portion of tissue at a given depth to the average echo amplitude within the same gated portion measured under the same conditions on a phantom filled with a "tissue-mimicking" material. A theoretical analysis shows that the index depends not only on the attenuation coefficient and the backscattering coefficient of the tissue but also on the depth of the measurement. It is demonstrated that it is feasible to measure the attenuation coefficient using the current system, and the reproducibility of the index measurement is evaluated on a normal thyroid.

Dextrans↗

PubMed1989

Overview of hemodynamic and non-hemodynamic factors associated with left ventricular hypertrophy.

The role of the heart in hypertension has finally emerged as a major issue of cardiovascular concern by the clinician, physiologist, pharmacologist, biochemist, and molecular biologist. This discussion provides an overview of the present state of knowledge and current areas of investigation in this active area of broad interest. Generally, these relate to: the active participation of the heart (e.g. hemodynamic, humoral, autocrine/paracrine); the adaptive response of the heart (i.e. hemodynamic); non-hemodynamic relationships (vis-a-vis, age, race, gender, humoral, coexistent disease); and current thoughts on mechanisms of so-called regression of left ventricular hypertrophy. Several antihypertensive classes of compounds are characterized by decreasing cardiac mass and left ventricular wall thicknesses. The angiotensin converting enzyme inhibitors are included among these agents; their physiological effects in producing "regression" are under active study as are the mechanisms responsible for these changes. These concerns are no longer of incidental or theoretical interest but have major impact on selection of antihypertensive therapy and the management of the patient with hypertension. Thus, the heart may participate actively in the pathogenesis and maintenance of the disease; it adapts to the vascular disease hemodynamically; but in this regard the response has both positive beneficial concerns as well as negative implications as an independent risk factor. These latter concerns should be explored in great depth before conclusions are made with respect to the long-term implications of antihypertensive therapy on the heart.

Antihypertensive Agents↗

PubMed2001

Validation of the language development survey (LDS): a parent report tool for identifying language delay in toddlers.

Two studies are reported demonstrating the reliability, validity, and clinical utility of the Language Development Survey (LDS; L. Rescorla, 1989) as a screening tool for the identification of expressive language delay in toddlers. In Study 1, 422 children (ages 24-26 months) were screened with the LDS in an epidemiological survey. The LDS manifested excellent concurrent validity with a brief direct screening measure of expressive vocabulary. Using the Rescorla (1989) Delay 3 cutoff of fewer than 50 words or no word combinations, 9.7% of the sample were language delayed (32 boys, 9 girls). In Study 2, 33 children identified as "at-risk" by the LDS Delay 3 cutoff and 33 typically developing children, matched on age, socioeconomic status, and gender, were seen for in-depth follow-up assessment approximately 3 weeks later. The LDS test-retest reliability was .97. The LDS correlated highly with Reynell Receptive and Expressive Language Scale scores, Bayley Mental Development Index, and Vineland Adaptive Behavior Composite. Sensitivity, specificity, positive predictive value, and negative predictive value between the screening LDS and the follow-up Reynell Expressive Language Scale were generally impressive. Finally, the at-risk group scored significantly lower than the LDS-identified typically developing group on all follow-up measures except the Child Behavior Checklist/2-3.

Child Language↗

PubMed1986

Evolutional and ecological implications of the properties of deep-sea barophilic bacteria.

The rate of reproduction of deep-sea bacteria from six different capture depths between 1957 and 10,476 meters was studied as a function of temperature and pressure. The results showed the following: the true deep-sea bacteria of different depths have several characteristics, presumably evolutionally derived, distinguishing them from each other and from bacteria of atmospheric-pressure environments; pressure plays a significant role in determining the distribution of oceanic life; and pressure-adapted bacteria are easily recovered from and ubiquitous in the deep ocean. Organisms evolving in habitats of different temperatures and pressures need to be studied to understand the physical limits of life, the distribution of life within the earth and its oceans, the role of organisms in organic diagenesis and petroleum formation, and the possible existence of life on and within other planets.

Journal Article↗

PubMed2001

Subperiosteal connective tissue grafts for pocket reduction and preservation of gingival esthetics: a case report.

BACKGROUND: Clinical studies and recent histological evidence following mucogingival surgery for the treatment of gingival recession have documented that when closely adapted to a previously exposed root surface, connective tissue is capable of forming a new attachment. Despite these findings, no clinical tests have been conducted to examine the ability of connective tissue to reduce probing depth (PD) and increase clinical attachment levels (CAL) when it is implanted into periodontal osseous defects. The purpose of this paper is to report the clinical results on a patient following 2 subperiosteal connective tissue grafts. METHODS: Subperiosteal connective tissue grafts were placed in 2 sites of periodontal bone loss and deep pocketing in one patient. Following flap reflection and root preparation, a connective tissue graft 1.5 to 2.0 mm in thickness was draped and sutured over each osseous defect and then completely covered by the external flap. RESULTS: Ten months following subperiosteal connective tissue grafting, tooth #7 had 4 mm of CAL gain. Tooth #10 had 3 mm of CAL gain 8 months postoperatively. Both teeth had 1 mm gain in gingival recession. Both teeth probed 3 mm postoperatively. CONCLUSIONS: When connective tissue was grafted into 2 periodontal osseous defects, there were significant reductions in probing depth and gains in CAL. There was minimal postoperative gingival recession. The new clinical attachment gain remained stable for 8 to 10 months following subperiosteal connective tissue grafting.

Alveolar Bone Loss↗

PubMed1992

Growth and development of the face in complete unilateral cleft lip and palate during prepubertal and pubertal periods.

Roentgencephalometry was used for the assessment of the growth and development of the face during prepubertal and pubertal periods in children with complete unilateral cleft lip and palate treated with the same methods. The first series included 16 boys and 15 girls, the second series consisted of 15 boys and 15 girls examined repeatedly at the beginning and at the end of the follow-up period. There were no definite differences in the growth rate of the face between the two periods of age. Therefore, the deterioration of overjet during puberty could be due to the depletion of the compensation and adaptation mechanisms after the previous orthodontic treatment rather than to the enhanced growth rate. As compared to other facial dimensions a lower growth rate showed during both periods the length of the anterior base, the depth of the maxilla and in particular the height of the upper lip. Developmental changes of variables of shape and position proceeded similarly during both periods of age. An exception represented the rotation of the mandible and the inclination of upper incisors. During the prepubertal period the lower jaw showed a very slight posterior rotation, while during puberty an anterior growth rotation was present. A rapid improvement of the proclination of upper incisors was attained only during the prepubertal period. It was accompanied by an improvement of overjet. However, during the period of puberty there was a renewed deterioration of overjet. A marked retrusion of the maxilla developed already in the prepubertal period. During both periods occurred an identical impairment of sagittal jaw relations and of the upper lip prominence, accompanied by a flattening of the facial profile and reduction of the nasolabial angle. The prominence of the nose increased, the angle of the cranial base remained unchanged. Intersexual differences were not demonstrated in any studied characteristics.

Adolescent↗

PubMed1983

Clinical pharmacology of lorazepam.

As a preanesthetic medication, lorazepam is available for oral, intravenous, or intramuscular administration. A parenteral dose of 0.04 to 0.06 mg per kg has been shown to be most effective as a preanesthetic medication in terms of antianxiety and antirecall effect (Table 1). Lorazepam has as its predominant advantage over other benzodiazepines the ability to produce anterograde amnesia reliably and for a relatively long duration. From an anesthesia standpoint, the drug finds its major usage as a premedicant or adjuvant (administered in the peri-induction period) to minimize the possibility of recall of unpleasant events during anesthesia and surgery. This is especially germane in patients who are unable to tolerate a sufficient depth of anesthesia to provide this amnesic effect on the basis of anesthetic agent alone. Quite often these patients are critically ill, and from a physiologic standpoint, their cardiovascular systems are unable to tolerate or adapt to moderate to deep anesthetic concentrations of the inhalation anesthetic agents. Even though the metabolic products of lorazepam are not active, the duration of action of this drug dictates that it not be used in the outpatient setting. Indeed, the drug probably should not be used in patients whose expected hospital stay is less than 72 hours. It appears that thrombosis or phlebitis after intravenous injection of lorazepam is less than with diazepam, especially if the drug is injected in small hand or arm veins. Most side effects of lorazepam are associated with central nervous system depression, are dose-related, and fairly predictable. Adverse central nervous system effects may be reversed by administration of physostigmine, but it is worthwhile to note that the duration of action of physostigmine, and repeated administration of physostigmine may be necessary. Lorazepam appears to be acceptable to both physicians and patients. There do not appear to be any obvious adverse interactions between lorazepam and other medications commonly used in anesthesia practice. Nevertheless, it appears that the major value of lorazepam to the anesthesiologist's armamentarium is its ability to prevent recall in appropriate situations.

Adjuvants, Anesthesia↗