Search PubMed⌕ Search

Biomedical subjects

C Lazarus

Publications and source records attributed to C Lazarus.

54 records · Page 3Linked to original sources

Effect of a maxillary glossectomy prosthesis on articulation and swallowing.

Swallowing was found to be substantially improved with the prosthesis. Less aspiration, less time necessary to complete the swallow, and greater variation in food consistency tolerated were all positive results of the prosthesis. In addition, videofluoroscopic studies of tongue movements during speech revealed that tip-alveolar /t-d/ and back-velar /k-g/ productions were more normal with the prosthesis. With the prosthesis, the understandibility of /t/ and /d/ was improved 20% and that of /k/ and /g/, 33%. It is clear that compromises must be effected in prosthesis design to facilitate improvement in both speech and swallowing. A large prosthetic mass in the oral cavity can also negatively change speech resonance. These issues are being investigated, as are acoustic and perceptual studies of speech articulation. Future research should address whether a combination of maxillary and mandibular prostheses would result in better speech and swallowing function. A mandibular prosthesis could replace missing teeth and alveolar contour that might influence speech and swallowing. A mandibular prosthesis might also allow construction of a smaller maxillary glossectomy prosthesis to interact with the mandibular prosthesis.

Articulation Disorders↗

The role of technetium-99m pentavalent DMSA in the management of patients with medullary carcinoma of the thyroid.

In order to assess the role of 99Tcm pentavalent dimercaptosuccinic acid (99Tcm (V)DMSA) scanning in the management of patients with medullary carcinoma of the thyroid, we imaged 10 patients with histologically proven disease. Nine of the 10 patients were scanned after removal of the primary tumour, but with symptomatic or biochemical evidence of recurrence. One patient was imaged prior to thyroidectomy. In eight of the 10 patients 99Tcm(V)DMSA successfully identified tumour deposits, and it has been shown in this study to be a cheap, convenient radiopharmaceutical for studying this group of patients, producing high-quality images with low radiation doses, and contributing significantly to patient management.

Adolescent↗

Swallowing disorders in closed head trauma patients.

Fifty-three closed head trauma patients with dysphagia were examined videofluorographically to determine the specific nature of their swallowing disorder. Eighty-one percent of the patients exhibited a delayed or absent swallowing reflex while approximately 50% of the patients suffered from reduced tongue control, and 33% had reduced peristalsis. Laryngeal disorders and cricopharyngeal dysfunction occurred in a small number of patients. The average head trauma patient exhibited more than one swallowing motility problem. Twenty patients aspirated, with delayed or absent swallowing reflex as the most common etiology for the aspiration. Many of these patients did not produce a reflexive cough during or after they had aspirated material into their airway. For this reason, and since the pharyngeal stage of the swallow is extremely difficult to assess with presently available bedside techniques, videofluorographic evaluation becomes an invaluable tool for identification of the precise nature of the swallowing disturbance, the presence of aspiration, and the etiology of the aspiration.

Adult↗

Carcinoma of the oesophagus in Ciskei.

An analysis of 100 consecutive cases of carcinoma of the oesophagus seen at the Cecilia Makiwane Hospital over a 4-month period is presented in order to show how the disease is seen in Ciskei. The short period of survival, similar to that reported in other southern African series, is contrasted with the improved outlook for patients in China, another high-incidence area, since the introduction there of mass cytological screening which leads to early detection.

Adult↗

Testosterone-induced oestrous cycle blockade in the rat: no evidence for prolactin involvement.

The relation between testosterone-induced oestrous cycle disruption and prolactin (Prl) secretion was studied in the female rat. Testosterone propionate (TP) injection on dioestrus 2 (day 0) of 4-day cycles induced cycle interruption for 12 days. A diurnal pattern of Prl secretion was observed from day 1 to day 6 with high levels in the afternoon and low levels in the morning. Cycle interruption also occurred in TP treated females given a dose of bromocriptine (BRC) known to completely block Prl secretion. Impairment of follicular growth resulted from TP treatment and from TP and BRC treatment as well. Until resumption of prooestrous, the follicular size did not exceed that noted during the dioestrous period of the cycle. Despite resumption of follicular growth from day 9 until day 14, ovulation only took place in a small number of animals. These results indicate that the antigonadotropic effects of Prl were not responsible for cycle disruption in our experimental model and that other mechanisms were in itself sufficient for the disruption. This was discussed in the light of previous findings in our laboratory.

Animals↗

A single plasma sample method to assess disease activity in patients with bone metastases from carcinoma of the prostate.

A single blood sample method was used to measure total skeletal activity during routine radionuclide bone scans in 114 patients with known carcinoma of the prostate. The method is based on the measurement of radioactivity in plasma after administration of 99mTc MDP and 51Cr EDTA, providing an assessment of total skeletal activity independent of renal function. The results showed a significant elevation of skeletal activity in patients with untreated bone metastases when compared with patients with no metastatic spread. Significant elevation with increasing extent of metastases was also shown, the highest activity being in patients with diffuse metastatic spread (superscan). Patients with treated metastatic disease showed significantly lower skeletal activity than patients with untreated bone metastases. The method requires the use of two radiopharmaceuticals injected as a mixture and potential errors may arise from pharmaceutical instability. In addition, elevation of total skeletal activity may be caused by coexistent metabolic bone disease. The results suggest that the measure may provide quantitative information in the assessment of the activity of bone metastases from prostatic carcinoma.

Bone Neoplasms↗

Monoclonal antibody HMFG-2 retains activity in vivo and binds to high molecular weight components expressed by metastatic breast cancers.

The monoclonal antibody HMFG-2 was raised against components of the human milk fat globule and human milk epithelial cells. It recognizes an epitope on glycoproteins of varying molecular weight; it is tumour-associated and expressed heterogeneously by most breast cancers. An intravenous injection of 131I-labelled HMFG-2 has been given to patients with recurrent cutaneous metastasis from breast carcinomas. Clearance of radioactivity from the plasma was measured and the label was shown to be carried on intact circulating antibody that had the ability to bind in vitro to the specific determinant as expressed by both the patients own tumour and by cultured breast cancer cells. Antibody was found to be associated with biopsy material taken from skin metastases 24 hours after administration of labelled antibody. However, the amount of radioactivity was insufficient for the production of a positive isotopic scan.

Antibodies, Monoclonal↗

Acid corrosive gastritis. A case report.

A patient who ingested concentrated hydrochloric acid and in whom early stricture of the gastric antrum formed is presented. Attention is drawn to the fact that the stomach usually bears the brunt of the injury following the ingestion of exogenous acid. Aspects of management are discussed, including the place of endoscopy and surgery.

Adult↗

Gibberellins and gene control in cereal aleurone cells.

The production of hydrolytic enzymes in the germinating cereal grain is considered as a model for plant cell differentiation. Recent literature is reviewed which suggests that gibberellins are involved in this process, but in a less straightforward manner than considered previously. It seems likely that only a subfraction of gibberellin is active and that production of this gibberellin is actually in the hydrolase-producing cells. These include aleurone cells and also the scutellar epithelial cells. At the intracellular level the action of gibberellin results in the accumulation of alpha-amylase mRNA and also mRNA for other unidentified proteins, referred to as gibb-ons. The alpha-amylase mRNAs are transcribed from two distinct gene families. The pattern of expression of alpha-amylase and gibb-on mRNAs is consistent with a common gibberellin-stimulated mechanism of control of for all of these genes. However it seems likely from experiments with ABA and from observations on gibb-on gene expression in non-aleurone cells that gibberellin does not have a role determining the specificity of gene expression, but rather acts as a general stimulator of mRNA accumulation.

Electrophoresis, Agar Gel↗

Influence of blood removal under ether anaesthesia on the release of prolactin during the oestrous cycle in the rat. Involvement of the ovaries.

The aim of this work was to study the stress-like effects of blood removal under ether anaesthesia at different stages of the di-oestrus period in 4-day cyclic female rats. Blood removal by heart puncture or laparotomy and bleeding from the abdominal vena cava both under ether anaesthesia were shown to precipitously evoked prolactin release on di-oestrus I morning and on di-oestrus II afternoon. Adrenalectomy did not prevent this effect from occurring on di-oestrus I morning following either procedure of blood removal. Ovariectomy completely suppressed the stress-like effects of ether anaesthesia whereas progesterone appeared capable of restoring prolactin release under these circumstances. No prolactin positive response to ether anaesthesia was observed on di-oestrus II morning, in unoperated control females.

Adrenalectomy↗

A hormonal and temporal analysis of the mechanisms involved in the control of ovulation induced by hemiovariectomy in the rat.

The present study was undertaken to investigate the mechanisms of the stress-related ovulatory effects of hemicastration in the rat. Previous work (Roos et al., 1976) had shown that ovulation induced by unilateral ovariectomy (ULO) was suppressed in adrenalectomized females when ULO was performed on dioestrus III at 10--11 h in 5-day cyclic rats. Using the same experimental schema an increase in blood progesterone within 1 to 4 hours after ULO has been found to be present in adrenal intact females and suppressed in adrenalectomized rats. PB treatment (30 mg/kg, i.p.) concomitant with ULO at 10--11 h on dioestrus III significantly decreased the number of ovulating females without preventing blood progesterone concentration to increase at 12--13 h. A partial blockade of ovulation resulted from PB injection at 13 or 18 h. The ovulatory effects of ULO observed in females injected with PB at 23 h on dioestrus III or at 5 h on prooestrus were identical to those observed in hemiovariectomized non PB treated females. Only a small proportion of hemiovariectomized females displayed an LH release at 15--16 h and 17.30 h--18.30 h on dioestrus III. In contrast a significant FSH release was observed in this interval of time following ULO. Microscopic examination of the ovaries on prooestrus at either 11 h or 16 h revealed the presence of corpora lutea with morphological features corresponding to very different stages of development. We can conclude that progesterone of adrenal origin constituted the trigger of ovulation and caused LH-release during a time period extending from 13 h to 23 h on dioestrus III following ULO in the rat.

Adrenalectomy↗

Effects of maneuvers on swallowing function in a dysphagic oral cancer patient.

This study examined the effects of three swallow maneuvers: (1) the supraglottic swallow (voluntary closure of the vocal folds prior to the swallow); (2) the super-supraglottic swallow (airway closure at the level of the arytenoid to base of epiglottis); and (3) the Mendelsohn maneuver (voluntary prolongation of laryngeal elevation and cricopharyngeal opening during swallow) on swallow functioning in a 47-year-old patient who underwent right composite resection for a squamous cell carcinoma of the right retromolar trigone. All maneuvers were employed during the same videofluorographic (VFG) swallow study conducted 6 months after the patient's surgery. Biomechanical analysis of 3-mL swallows defined the extent and timing of tongue base retraction to the posterior pharyngeal wall, laryngeal elevation, laryngeal closure and cricopharyngeal opening during swallows with and without maneuvers. Airway closure duration was prolonged during supraglottic and super-supraglottic swallows, but aspiration was not eliminated. Use of the Mendelsohn maneuver improved coordination and timing of pharyngeal swallow events, including timing of posterior movement of the tongue base to the pharyngeal wall in relation to airway closure and cricopharyngeal opening, with elimination of aspiration. The Mendelsohn maneuver compensated for anatomic and physiologic changes in the oropharyngeal swallow and enabled reinstatement of safe oral intake in this surgically treated head and neck cancer patient who was previously unable to take nutrition orally.

Carcinoma, Squamous Cell↗

Psychophysiologic correlates of nocturnal penile tumescence in normal males.

Despite increasing clinical reliance on nocturnal penile tumescence (NPT) testing for the differential diagnosis of male impotence, little is known at present about the relationship between NPT and other aspects of sleep and waking psychophysiology. This study investigated patterns of NPT, sleep, and EEG hemispheric asymmetry in 20 male subjects, using standard polysomnographic laboratory procedures for the assessment of sleep and NPT, and a method of EEG amplitude integration developed by Goldstein. Additionally, the effects of daytime sexual activity and mood state on the duration and amplitude of NPT were studied. Overall, the results of this study confirmed the well-documented relationship between NPT and stage REM, as well as demonstrating a strong association between NPT phase and nondominant hemisphere activation. Furthermore, this association appeared to strengthen over the course of the night. Hemispheric asymmetry and stage REM were also closely linked throughout. On the other hand, no significant correlations were found between daytime sexual activity or mood state and NPT. It is suggested that concurrent assessment of hemispheric asymmetry may strengthen the diagnostic power of NPT testing in impotence cases involving central organic etiology.

Adult↗

Association of esophageal cytological abnormalities with vitamin and lipotrope deficiencies in populations at risk for esophageal cancer.

Esophageal brush cytological screening was undertaken and blood concentrations of micronutrients (vitamin A, E, B12, folic acid and methionine) determined from adults at risk for esophageal carcinoma (EC) in Transkei and Ciskei, Southern Africa. Age-standardised EC rates per 100,000 per annum for both sexes in high, intermediate and low risk districts in Transkei were 74, 51 and 34, respectively. Corresponding rates in high and low EC risk districts in Ciskei were 129 and 9, respectively. Esophageal cytological changes including esophagitis, signs of folic acid deficiency, cellular atypia, dysplasia and cancer, were more prevalent in patients from high than from low EC risk areas. Dietary questionnaires revealed that corn was the main dietary staple in all populations, but that lower intakes of green vegetables, fruits and animal protein occurred in the high risk areas. Significantly lower concentrations of vitamins A, E, B12 and folic acid were present in the blood of patients presenting with cellular dysplasia or malignancy than in cytologically normal patients and in patients from low risk areas. Concentrations of red cell and plasma folate were significantly lower in patients presenting with cytological signs of folic acid deficiency or cellular atypia. The association of vitamin A, vitamin E and folic acid deficiencies with specific esophageal cytological abnormalities in populations at risk for EC is reported for the first time.

Adult↗