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D Harari

Publications and source records attributed to D Harari.

At least 19 recordsLinked to original sources
PubMed1998

Does a secular trend exist in the distribution of occlusal patterns?

The existence of a secular trend in the distribution of occlusal patterns was studied in two generations of children. Study models and demographic data of a sample of 265 children from the previous generation (group A) and recordings of clinical examinations of 988 children from the present generation (group B) served as the data base for this study. Children in whom caries affected the occlusion and those in the deciduous dentition stage were excluded. Thus, occlusal analysis was performed for 102 children in group A and 703 in group B. A dramatic decrease was found in the prevalence of caries affecting the occlusion. No difference existed between the two groups with respect to molar and canine anteroposterior relationships. However, there was a decrease in the prevalence of normal occlusion accompanied by an increase of Class I malocclusion.

Adolescent↗
PubMed1997

FGF plays a subtle role in oligodendrocyte maintenance in vivo.

Numerous in vitro studies indicate that fibroblast growth factors (FGFs) play a role in both the development and maintenance of oligodendrocytes. Addition of FGF to mature oligodendrocytes in culture was reported to downregulate the expression of genes encoding proteins of the myelin sheath and to induce a loss of myelin compaction. In this study, a model was developed to functionally block FGF signaling in oligodendrocytes in vivo, by generating transgenic mice expressing a dominant-negative FGF receptor (FGFR1), under the control of the myelin basic protein (MBP) promoter. To demonstrate the effectiveness of this model, truncated FGFR1 was first overexpressed in an FGF-responsive cell line in vitro. It was confirmed that FGF-signalling was blocked in these cells. Subsequently, five independent transgenic lines ("MBP-FRD") were generated. Three lines expressing the highest level of the transgene were further studied. Initial investigation by Western blot and light microscopic analyses revealed no apparent alterations in myelination of the MBP-FRD mouse brains. However, ultrastructural analysis of myelinated optic nerve fibres from two independent MBP-FRD lines revealed a significant increase in myelin thickness as a function of fibre diameter for both transgenic lines (13% and 16% increase). This increase in myelin thickness was not accompanied by alterations in myelin compaction. These results support the idea that FGF signaling in oligodendrocytes plays a role in the modulation of axon myelination in vivo.

Animals↗
PubMed1997

Constipation-related symptoms and bowel program concerning individuals with spinal cord injury.

PURPOSE: To determine the prevalence of constipation-related symptoms in individuals with chronic spinal cord injury (SCI), to describe the bowel program as reported by patients and including use of bowel medications and evacuation techniques, and to examine the clinical, functional and pharmacological risks of difficulty with evacuation. PATIENTS AND METHODS: This is a cross-sectional study of all in-patients at least 3 months beyond acute injury, on the West Roxbury/Brockton VAMC SCI Service, during a 10 month period (n = 197). Clinical, functional, and medication data were abstracted from medical and nursing records. Individual interviews were conducted with all available participants (n = 161, 82%) regarding bowel-related symptoms and treatment over the previous 1 month period. The study definition of difficulty with evacuation was spending more than 1 h per episode of bowel evacuation. RESULTS: Forty-one percent of the 161 interview responders spent more than 1 h on bowel evacuation, 50% reported abdominal distension and 38% reported abdominal pain, 27% reported headaches or sweats relieved by having a bowel movement, and 33% reported fecal incontinence at least once a month. The bisacodyl suppository was the most commonly used laxative agent, while docusate was the most popular oral agent. Subjects with difficulty with evacuation (n = 66) were compared with those who spent less than 1 h on evacuation (n = 95). Factors associated with difficulty with evacuation were tetraplegia, Frankel grade A/B, laxative use, polypharmacy, previous urinary outlet surgery, and symptoms of abdominal pain and distension. CONCLUSION: Constipation-related symptoms are highly prevalent in individuals with spinal cord injury, despite considerable laxative use. Our findings suggest that difficulty with evacuation can be predicted on the basis of a patient's clinical profile.

Adult↗
PubMed1997

How do older persons define constipation? Implications for therapeutic management.

This study examined the relation between bowel-related symptoms and self-report of constipation in 10,875 subjects aged 60 years and over, who participated in the 1989 National Health Interview Survey. Subjects reporting constipation "always" or "mostly" over the past 12 months (n = 594) were compared with those who reported never having the symptom (n = 4,192). Straining (adjusted odds ratio 66.7; 95% confidence interval 31.5, 142.4) and hard bowel movements (25.6; 16.7, 38.7) were most strongly associated with self-report of constipation. These findings suggest that treatment for constipation in the older population should be directed as much or more at facilitating comfortable rectal evacuation, as increasing bowel movement frequency.

Aged↗
PubMed1997

Occlusal traits in a group of school children in an isolated society in Jerusalem.

The prevalence of occlusal features in 939 children, aged 6-13 years, belonging to an ultra-orthodox community of Jewish Ashkenazi descent living in Jerusalem was studied clinically. Sexual dimorphism was found for overjet, overbite, and habit practising. About one-quarter of the sample exhibited some degree of occlusal mutilation due to caries, thus creating a 'caries-affected' subgroup, the rest forming the 'caries-free' subgroup. In the latter set, normocclusion was scarce (7.4 per cent), Class I being the most frequent malocclusion (49.1 per cent). Caries had a significant effect on the symmetry of bilateral occlusal relationships, lower dental midline deviation, and on crowding/spacing conditions in the mixed dentition stage (except for the maxilla in late mixed dentition). The low prevalence of normocclusion can be attributed to genetic background, environmental influences and the definition attached to normal occlusion.

Adolescent↗
PubMed1997

The effect of nonisodiametric design on the ease of extracting chronically implanted pacemaker leads.

Extracting permanently implanted transvenous pacemaker leads is often difficult because a fibrous sheath tends to trap the lead at various points along its course. Because many leads have bulbous or nonisodiametric portions, extraction may be rendered even more troublesome, because it is difficult to pull the larger portion through the narrow areas of the sheath. Furthermore, forceful extraction may have dire consequences, such as cardiac laceration. A study was undertaken in animals to evaluate the effect of lead isodiametricity on lead extraction. The results show that any increase in the diameter of the lead tip greatly reduces the ease of its removal. Consequently, leads designed to be isodiametric throughout their entire lengths will greatly enhance their removability.

Animals↗
PubMed1996

Bowel habit in relation to age and gender. Findings from the National Health Interview Survey and clinical implications.

BACKGROUND: Constipation is widely considered to be a common problem among the elderly, as evidenced by the high rate of laxative use in this population. Yet, age-related prevalence studies of constipation generally do not distinguish between actual alteration in bowel movement frequency and subjective self-report of constipation. OBJECTIVE: To determine the relationship between advancing age and bowel habit. METHODS: We employed data collected on 42,375 subjects who participated in the National Health Interview Survey on Digestive Disorders based on interviews with a random nationwide sample of US households. We examined the following characteristics reported by this population according to selected age groupings by decade: constipation, levels of laxative use, and two bowel movements per week or less. RESULTS: Contrary to conventional wisdom, there was no age-related increase in the proportion of subjects reporting infrequent bowel movements. Nonetheless, the prevalence of self-report of constipation increased with advancing age, with a greater proportion of women reporting this symptom than men across all age groups. Laxative use also increased substantially with aging; while women were more likely to use laxatives than men, this effect attenuated with advancing age. A U-shaped relationship was observed between advancing age and bowel habit in men and women; 5.9% of individuals younger than 40 years reported two bowel movements per week or less compared with 3.8% of those aged 60 to 69 years and 6.3% of those aged 80 years or older. This relationship persisted after adjusting for laxative use. CONCLUSION: These findings suggest that a decline in bowel movement frequency is not an invariable concomitant of aging. In elderly patients who report being constipated, it is essential to take a careful physical, psychological, and bowel history rather than to automatically assume the need for laxative use.

Adult↗
PubMed1996

The resolution of palatally impacted canines using palatal-occlusal force from a buccal auxiliary.

Palatally impacted canines can usually be mechanically drawn directly to the labial arch wire after they have been surgically exposed. Occasionally, the direct line between the impacted tooth and the arch wire is obstructed by the presence of the root of the lateral incisor, or the tooth is very superiorly displaced, which makes direct traction ill-advised and impractical. In this situation, it is recommended that the tooth be erupted vertically downward, through the palatal tissue on the palatal side of the dental arch, as a first stage and, only then moved buccally into its place in the arch. This article describes a method whereby an auxiliary spring is placed on the buccal side of the arch to produce the vertical and palatal traction needed. There are no palatal accessories, and the auxiliary is tied in, "piggy-back" fashion, over the main base arch, by using the multibracketed appliance already present.

Cuspid↗
PubMed1996

Dens evaginatus of anterior teeth. Literature review and radiographic survey of 15,000 teeth.

Case reports published between 1970 and 1995 that describe the characteristics of dens evaginatus of anterior teeth were reviewed. In addition, a radiographic survey of 15,000 anterior teeth was conducted to determine the occurrence of this developmental malformation. In this survey, dens evaginatus was found in about 1% of the anterior dentition and was more frequent in the maxilla, particularly in the lateral incisor. This anomaly was less frequent in the mandible.

Adult↗
PubMed1996

Conservative treatment of dens evaginatus of anterior teeth.

Dens evaginatus is a developmental malformation characterized by the presence of an extra cusp. In the anterior dentition, dens evaginatus is more commonly found in the maxilla and on the palatal surface of the tooth. Treatment may include root canal therapy followed by either an aesthetic restoration or a full crown coverage. In cases of mesiodens, supernumerary teeth or crowded dentition, extraction is often indicated. Presented is a case of a conservative treatment modality of dens evaginatus in a mandibular central incisor.

Child↗
PubMed1995

Constipation in the elderly.

Management is not as straightforward as it appears. Patients often have associated conditions that predispose to or result from constipation. An OTC laxative habit may confound the workup and frustrate treatment. Overall evaluation is required, lest constipation progress to a medical crisis that requires hospital admission.

Aged↗
PubMed1995

Correlates of regular laxative use by frail elderly persons.

PURPOSE: To examine the demographic, clinical, and pharmacological correlates of regular laxative use in elderly persons residing in a long-term care setting. METHODS: This was a cross-sectional study using retrospective record review undertaken in an academically affiliated long-term care facility in the United States. All individuals residing in the institution for at least 1 month (n = 694) were characterized regarding use of laxatives. Regular laxative use was defined as more than 30 doses of laxatives, stool softeners, or enemas taken over the most recent 1-month period. RESULTS: Residents with regular laxative use (n = 349) were compared with those who received no laxatives (n = 227). Factors significantly associated with regular laxative use at the P < 0.05 significance level were simultaneously included in a multiple logistic regression model. Factors associated with regular laxative use were immobility, Parkinson's disease, diabetes mellitus, and use of iron supplements, calcium channel blockers, and antidepressants with moderate to strong anticholinergic properties. CONCLUSION: Regular laxative use is often associated with neurologic dysfunction that directly or indirectly affects the gut, or medications known to depress colonic motility. Identification of potentially modifiable correlates of regular laxative use in older individuals may suggest management strategies to avoid or reduce laxative, stool softener, and enema requirements, improve constipation symptoms, and enhance quality of life for the frail elderly population.

Aged↗
PubMed1994

An age-related investigation of urinary tract symptoms and infection following urodynamic studies.

One hundred and thirty-nine patients undergoing urodynamic investigation were studied. Urine samples taken at the time of the test and at 72 hours afterwards were cultured and data on symptoms following the test were collected. The overall infection rate was 15.8%. Men and women aged over 70 years were no more likely than younger subjects to become infected. A high residual urine volume was not associated with an increased risk of infection. The only clinical feature associated with infection following the test was an increase in incontinence. These findings were all in contradiction to previous studies on smaller numbers of patients.

Adult↗
PubMed1994

Constipation: assessment and management in an institutionalized elderly population.

OBJECTIVES: To examine prescribing and utilization patterns of laxatives, stool softeners, and enemas in a large, long-term care facility, to compare self-reports of constipation with specific, bowel-related symptoms in residents of this facility, and to examine concordance between bowel symptoms reported by residents and the assessments of the nursing staff. DESIGN: Cross-sectional study. SETTING AND SUBJECTS: All individuals residing in an academically oriented long-term care facility in the United States for at least 1 month (n = 694). MEASUREMENTS: Clinical, functional, and medication data were abstracted from the medical and nursing records. Individual interviews regarding bowel-related symptoms were conducted with all able participants (n = 456 (66%)) and their respective primary nurses, and concordance was determined. The study definition of symptom-specific constipation was no more than 2 bowel movements per week and/or straining on more than 1 in 4 bowel movements. RESULTS: Fifty percent (n = 367) of all residents used at least 1 daily laxative, stool softener or enema during a 1-month study period. Over half of all laxative users (n = 200) took more than 60 doses per month. Stool softeners were most commonly prescribed, followed by saline laxatives, stimulant laxatives, hyperosmolar laxatives, and bulk laxatives. Forty-seven percent (n = 213) of the 456 interview responders reported constipation ("self-reporters"), but only 62% of self-reporters met the study criteria for symptom-specific constipation. Concordance between resident's and nurse's report regarding specific bowel symptoms was only fair to slight (kappa 0.12-0.38). Self-reporters of constipation took almost twice as many laxatives, stool softeners, and enemas as residents who did not report constipation.

Aged↗
PubMed1993

Constipation in the elderly.

OBJECTIVE: To explore the distinction between true clinical constipation and the subjective complaint of constipation in elderly people and to review the pathophysiology, symptoms, diagnosis, causes, and treatment. DATA SOURCES: A computer-assisted and manual search of the English language literature using MEDLINE 1966-1991, Index Medicus 1988-1992, reference lists of selected articles, and relevant textbooks. STUDY SELECTION: Studies that provide information on lower bowel function and laxative and enema use in the elderly subjects were reviewed. Article selection was not limited by study design. DATA EXTRACTION: Relevant data were abstracted from the results of physiological, cohort and case-control studies, and clinical trials. The text discusses the methodological strengths and flaws of these studies and excludes management approaches formulated from uncontrolled clinical observation. RESULTS OF DATA SYNTHESIS: Constipation of the elderly is not well defined in the current literature. Self-reported constipation and laxative use increase with age, while a similar escalation in true clinical constipation is not shown. Physiological changes in the lower bowel predisposing toward constipation do not occur with normal aging. Patient selection criteria for studies examining the pathophysiology of constipation differ in their definition of constipation and their inclusion of coexisting chronic illness. Nevertheless, there is consistent evidence for prolonged transit through the sigmoid colon and rectum, especially in frail elderly patients, and reduced rectal tone with impaired sensation, particularly in patients with rectal impaction. Few studies rigorously examine "risk factors" and non-pharmacological interventions in constipation. The results of most laxative trials require cautious interpretation because of inclusion of patients without diagnostically proven constipation, use of combined laxative preparations, and unreliable outcome measures. Certain laxative agents however appear more appropriate for use in elderly people. CONCLUSION: Although the subjective complaint of constipation and habitual laxative use increase with age, the epidemiological data suggest that true clinical constipation does not. Physiological changes predisposing toward constipation are not an inevitable consequence of aging, but appear to be specific to the condition. The available data do not confirm many suspected "risk factors" nor the benefits of commonly used non-pharmacological and pharmacological treatments, but they do provide enough information to formulate a practical approach to constipation in elderly persons.

Aged↗
PubMed1991

Plasma exchange in the treatment of Refsum's disease (heredopathia atactica polyneuritiformis).

Five cases of heredopathia atactica polyneuritiformis (HAP--Refsum's disease) were treated by serial plasma exchanges. In all patients a reduction in calorie intake and body weight had been associated with a rise in plasma phytanic acid, followed by an exacerbation of the ataxia and neuropathy. Lowering the plasma phytanic acid by plasma exchange produced a rapid clinical improvement. The main indication for plasma exchange in HAP is a severe or rapidly worsening clinical condition. A lesser indication is failure of dietary management to reduce a high plasma phytanic acid level.

Adult↗
PubMed1990

The management of empyema thoracis by thoracoscopy and irrigation.

A technique of irrigation for the management of empyema thoracis is described. Initial thoracoscopy using a laparoscope under general anaesthesia enabled adequate debridement and breakdown of loculi within the empyema cavity under direct vision. Following this procedure irrigation of the cavity with two tubes was started and continued until three consecutive cultures of drained irrigation fluid became sterile. The procedure was then discontinued. The results in 14 patients are presented using this method, irrigation was required for an average of 14 days. Patients remained in hospital for an average of 4.8 weeks. Tuberculous empyema was not found to be a contra-indication to the irrigation technique.

Adult↗