Self-reported musculoskeletal pain among dentists in South Africa: A 12-month prevalence study

INTRODUCTION

Musculoskeletal trouble (ache, pain, discomfort) originating in the neck, shoulder, and back is a common occupational hazard among dental professionals worldwide, The significance of this problem justified research into the prevalence of these symptoms among dentists in South Africa for which there is currently no information.

AIMS

The aim of this study was to investigate the one-year prevalence of self-reported musculoskeletal trouble in the neck, shoulder, and lower back areas among dentists in South Africa.

METHODS

A survey questionnaire was forwarded to all members of the South African Dental Association whose email addresses were recorded on the Association data base. The email survey was performed using the previously validated Nordic Musculoskeletal Questionnaires.

RESULTS

This cross sectional study revealed a self-reported 12-month prevalence of musculoskeletal trouble (ache, pain, discomfort) among dentists in South Africa of 77.9% involving the neck, 69.8% the lower back, and 72.4% the shoulders, Multiple regression analysis showed that a

Relationship between Changes in Thymic Emigrants and Cell-Associated HIV-1 Dna in HIV-1-Infected Children Initiating Antiretroviral Therapy

Objectives and methods

To investigate the relationship between cell-associated HIV-1 dynamics and recent thymic T-cell emigrants, HIV-1 DNA and T-cell receptor rearrangement excision circles (TREC, a marker of recent thymic emigrants) were measured in peripheral blood mononuclear cells in 181 samples from 33 HIV-1-infected children followed for 96 weeks after antiretroviral therapy (ART) initiation.

Results

At baseline, HIV-1 DNA was higher in children with higher TREC ( P=0.02) and was not related to age, CD4 or HIV-1 RNA in multivariate analyses ( P>0.3). Overall, TREC increased and HIV-1 DNA decreased significantly after ART initiation, with faster HIV-1 DNA declines in children with higher baseline TREC ( P=0.009). The greatest decreases in HIV-1 DNA occurred in children with the smallest increases in TREC levels during ART ( P=0.002). However, this inverse relationship between changes in HIV-1 DNA and TREC tended to vary according to the phase of HIV-1 RNA decline ( P=0.13); for the same increase in TREC, HIV-1 DNA decline was much smaller during persistent or transient viraemia compared with stable HIV-1 RNA suppression.

Conclusions

Overall, these findings indicate that TREC levels predict HIV-1 DNA response to ART and suggest that immune repopulation by thymic emigrants adversely affects HIV-1 DNA decline in the absence of persistent viral suppression, possibly by providing a cellular source for viral infection and replication.

Intravitreal injection of octreotide acetate

This study was conducted to determine the feasibility of injecting the somatostatin analogue, octreotide acetate (OA), into the vitreous cavity. Previous work suggests that octreotide effectively inhibits angiogenesis in vitro, thus its use in vivo may slow the progression of proliferative eye disease. Fifty micrograms of aqueous OA in 50 microliters aqueous solution was injected into the mid-vitreous of kitten eyes (n = 6), and OA levels were monitored over 4 days. A long-acting release form of octreotide (OA-LAR) was also injected into the mid-vitreous of rabbit eyes at doses of 0.36 (n = 16), 1.1 (n = 1), 2.1 (n = 1), 4.05 (n = 1), 8.2 (n = 1), and 36 mg (n = 3) in solution; and octreotide concentrations were measured at various time points over 42 days. OA concentrations were determined by a highly specific radioimmunoassay. Aqueous octreotide was eliminated rapidly (t1/2 = 16 hours) from the vitreous of the kitten eye, with only negligible amounts recoverable 4 days post-injection. In the long-acting form, OA in the rabbit eye reached peak levels at 28 days. By 42 days, OA levels had declined to the 14-day level. Doses of OA-LAR of 1.1 mg or less produced no gross evidence of clinical toxicity and elicited no grossly visible ocular side effects. Doses greater than 1.1 mg produced significant toxicity, including cataracts and rubeosis. The 28-day peak release for long-acting OA implies that monthly intravitreal injections could provide continual high levels of OA. Intravitreal injection of long-acting OA provides sustained, high concentrations of drug, and deserves further study as a potential treatment of proliferative eye diseases.

Detection of occult gastrinomas with iodine 125-labeled lanreotide and intraoperative gamma detection

BACKGROUND

Surgical exploration for gastrinoma has a high failure rate because of small primary tumors and occult metastasis. Despite extensive preoperative and intraoperative tumor localization, only 30% to 40% of patients with gastrinoma are cured by surgery. Two patients with unlocalized gastrinomas were studied with intraoperative gamma detection of an iodine 125-labeled somatostatin analog, lanreotide, to localize their tumors.

METHODS

Both patients were challenged before operation with 100 micrograms of octreotide acetate, and both had circulating gastrin levels suppressed by greater than 50%. Iodine 125-labeled lanreotide (100 to 150 muCi) was injected during exploration, and an intraoperative gamma detector was used to detect tumor binding of the analog.

RESULTS

In patient 1 a single source of increased counts was discovered in a retroduodenal lymph node, which was excised; no other tissue was removed. Histologic study of this node failed to demonstrate tumor; however, the patient's gastrin level was normal (63 pg/ml) 4 months after operation. In patient 2 five areas of increased counts were discovered and excised. Three of these five areas had visible tumor on microscopic examination. Three months after operation the patient's fasting gastrin level was 103 pg/ml.

CONCLUSIONS

Intraoperative gamma detection of radiolabeled peptides may allow the localization of occult tumors that contain specific peptide receptors.

Postreceptor signal transduction mechanisms involved in octreotide-induced inhibition of angiogenesis

BACKGROUND

Somatostatin analogues inhibit peptide release and cell growth through multiple postreceptor signal transduction mechanisms (PRSTM), including G proteins (GP), cyclic adenosine monophosphate (cAMP), calcium, protein kinase C (PKC), and tyrosine phosphatase (TP). Octreotide acetate (OA), a somatostatin analogue, has been shown to inhibit angiogenesis; however, the PRSTM involved are unknown.

METHODS

Fertilized chicken eggs were obtained and incubated. On day 3, embryos were removed and placed in plastic wrap hammocks. On day 7, disks containing OA, test substances that interfere with PRSTM, or combinations of OA plus a test substance were placed on the developing chorioallantoic membrane. Blood vessel growth under each disk was assessed at 24 hours. Data were evaluated by chi-squared analysis.

RESULTS

OA's ability to inhibit angiogenesis is significantly diminished when combined with calcium, bradykinin (increases calcium), pertussis toxin (inhibits GP), or 3-isobutyl-1-methylxanthine (increases cAMP). In contrast, no significant decrease is noted in OA's ability to inhibit angiogenesis when combined with phorbol ester (activates PKC) or vanadate (inhibits TP).

CONCLUSIONS

OA-induced inhibition of angiogenesis is GP, calcium, and cAMP dependent and is PKC and TP independent. Better understanding of the PRSTM involved with OA-induced inhibition of angiogenesis may lead to enhancement of OA's effect on angiogenesis.

Protective effect of doxorubicin in vitamin C or dimethyl sulfoxide against skin ulceration in the pig

BACKGROUND

Accidental extravasation of doxorubicin leads to skin necrosis and significant morbidity. Based on our previous work in the rat, we hypothesized that the free radical scavengers dimethyl sulfoxide (DMSO) and vitamin C prevent doxorubicin-induced skin ulcers in white swine.

METHODS

Fifteen white swine were anesthetized and injected with 0.5 mg of doxorubicin (1 mg/ml) intradermally delivered in saline, 10% DMSO, 20% DMSO, vitamin C (1 mg/ml), or vitamin C in 20% DMSO. Presence of skin ulceration and ulcer size, in the two greatest dimensions, was determined weekly for 3 weeks.

RESULTS

Delivery of doxorubicin in DMSO and/or vitamin C lowered the ulcer incidence from 87% to 27% (p < 0.0001) when compared with delivery in saline.

CONCLUSION

We conclude that the free radical scavengers DMSO and vitamin C are capable of lowering the incidence of doxorubicin-induced skin ulcers and could significantly lessen the morbidity associated with doxorubicin extravasation.

Treatment of oral cancers using iridium-192 interstitial irradiation

OBJECTIVE

To assess retrospectively the outcome and morbidity of Iridium-192 brachytherapy in the treatment of oral cancers.

DESIGN

Retrospective audit of cases treated between 1981 and 1991.

SETTING

Newcastle upon Tyne, England.

SUBJECTS

73 patients with oral cancer treated with Iridium-192.

MAIN OUTCOME MEASURES

Local control, crude and cause specific survival, and local morbidity.

RESULTS

Seventy four cases of squamous cell carcinoma of the oral cavity were treated using interstitial Iridium-192. The disease specific 5-year survival rates were 69% for T1, 67% for T2, and 0% for T3 tumours. Mortality from recurrent cancer was 20%, and from intercurrent disease was 28%. The incidence of major radiation induced morbidity was 11%, and the local control rate was 81% for T1, 69% for T2, and 50% for T3 tumours.

CONCLUSION

Interstitial radiotherapy remains a viable and valuable mode of treatment for a small proportion of patients presenting with early (T1 and T2) oral cancers.

Inhibition of angiogenesis by somatostatin and somatostatin-like compounds is structurally dependent

We have previously demonstrated that somatostatin analogues SMS 201-995 and RC-160 inhibit angiogenesis using the chorioallantoic membrane (CAM) of the developing chicken embryo. In this study, we evaluated the ability of native somatostatin 14 and nine somatostatin analogues to inhibit angiogenesis. Two-millimeter methylcellulose disks containing 50 micrograms of somatostatin or somatostatin analogue were implanted on the CAM of 6- to 7-day-old shell-less chick embryos. Inhibition of blood vessel growth was visually assessed and graded in the region of the disk 24-36 hr following implementation. The analogues SMS 201-995 and RC-160 showed statistically significant inhibition of neovascularization when compared to native somatostatin 14. The amino acid homology comparison of the nine analogues revealed that individual differences in their abilities to inhibit angiogenesis may be structurally dependent.

Cowden's disease: a rare but important manifestation of oral papillomatosis

A case of Cowden's disease is reported, and possible differential diagnosis for the oral lesions is suggested.

DMSO protects against adriamycin-induced tissue necrosis

Inadvertent extravasation of Adriamycin (Adria) can result in severe tissue necrosis. The mechanism of this tissue damage is believed to be the release of free radicals into the tissue. Topical applications of dimethylsulfoxide (DMSO) used after Adria extravasation have been shown to decrease ulcer size. This may be due to DMSO's ability to scavenge free radicals. However, effective topical therapy requires prompt recognition of extravasation, which is often difficult. We hypothesized that the delivery of Adria in low concentrations DMSO would reduce Adria-induced ulcer size and ulcer incidence caused by Adria extravasation. To test this hypothesis, 180, male Sprague-Dawley rats were randomly allocated into three treatment groups of 60 each. All three groups received intradermal injections of Adria (1 mg) diluted in 0.5 cc of saline (Group 1), 10% DMSO (Group 2), or 20% DMSO (Group 3). Rats were observed for 4 weeks. Ulcer incidence (%) and size of ulcers (mm2) were assessed over time. Area of skin ulceration was calculated as the product of the two greatest diameters. Statistical evaluation of the differences in incidence and ulcer size between Group 1 and Groups 2 or 3 were evaluated using analysis of variance. Delivery of Adriamycin in 10 or 20% DMSO resulted in a statistically significant (P less than 0.001) decrease in the incidence of ulceration caused by intentional Adria extravasation.

Somatostatin analogues inhibit angiogenesis in the chick chorioallantoic membrane

The mechanism responsible for alterations in tumor growth following administration of somatostatin analogues is unknown. Somatostatin analogues, SMS 201-995 and RC-160, have demonstrated the potential to inhibit both tumor growth and vascularity, in vivo and in vitro. We hypothesized that SMS and RC-160 inhibit angiogenesis and this inhibition may alter tumor growth. To test this hypothesis, 2 mm methylcellulose disks containing concentrations of SMS 201-995 and RC-160 at 0, 0.5, 2.5, or 50 micrograms per disk, were implanted on the chorioallantoic membrane (CAM) of 6- to 7-day-old shell-less chick embryos. Inhibition of blood vessel growth in the region of the disk was visually assessed 24-36 hr following disk implantation and graded (0-4) based on the radius of the zone of inhibition from the center of the disk. The overall incidence of inhibition for the somatostatin analogues at concentrations of 0.5, 2.5, and 50 micrograms per disk was 13, 56, and 61% for SMS and 27, 49, and 68% for RC-160, respectively. Overall incidence of inhibition for the positive (inhibitory) control was 70.5% and those for buffer (negative) controls were 3-14%. Somatostatin analogues were associated in a dose-related fashion with both a greater percentage of inhibition of blood vessel growth and an increased grade of inhibition. Inhibition of angiogenesis may be a mechanism responsible for the tumor regression observed in vivo following SMS or RC-160 therapy.

Successful transcutaneous external pacing for asystole following cardiac arrest

We report a case of successful transcutaneous external pacing for out of hospital cardiac arrest causing asystole.

Fatal Stevens-Johnson syndrome following urography with iopamidol in systemic lupus erythematosus

A 46 year old white woman with active systemic lupus erythematosus developed a skin rash 8 hours after intravenous urography with the non-ionic contrast medium iopamidol. Severe Stevens-Johnson syndrome with erythema multiforme, intrahepatic cholestasis, pulmonary infiltrates and acute renal failure ensued, leading to her death. Although non-ionic contrast media are generally less toxic than traditional ionic agents, their use in patients with immunological disease may be hazardous.