Effect of whole-body vibration on the low back. A study of tractor-driving farmers in north India

STUDY DESIGN: A retrospective cohort study of tractor-driving farmers (study group) and non-tractor-driving farmers (control group) matched for age, gender, generic/ethnic group, land-holding, and work routines. OBJECTIVES: To determine, using magnetic resonance imaging and clinical investigations, the effect of whole-body vibrations on the back in tractor-driving farmers. SUMMARY OF BACKGROUND DATA: Low back pain and pathologic changes in the lower backs of tractor drivers have been reported. However, no study with a control group matched for work-related risk factors has been reported. METHODS: Fifty tractor-driving farmers were compared with 50 non-tractor-driving farmers matched for age, gender, ethnic group, land-holding, and work routine. Both groups were interviewed for details of work routine, assets held, family profile, and vibration exposure to assess the influence of these parameters on signs and symptoms of backache. Magnetic resonance imaging was done to assess the effect of exposure on whole-body vibration and degenerative changes in the back. Vibration measurements also were done on tractors to observe the actual severity of the vibrations. RESULTS: Regular work-related backache was more common among tractor-driving farmers (40%) than among non-tractor-driving farmers (18%, P = 0.015). Anthropometric evaluation showed abdominal girth and weight to be significantly higher in tractor-driving farmers (P = 0.006 and 0.046, respectively), whereas while height and arm span were similar between the two groups. Clinical examination for evidence of disc or facet degeneration showed no difference between the two groups. Evaluation of magnetic resonance images of tractor-driving farmers and non-tractor-driving farmers by an orthopedic surgeon, radiologist, and neurosurgeon showed degenerative changes to be similar between the two groups (P > 0.050). CONCLUSIONS: Tractor-driving farmers report backache more often than non-tractor-driving farmers, but no significant objective differences on clinical or magnetic resonance imaging evaluation were found between the two groups.     

Cerebral haemodynamics in patients with chronic renal failure: effects of haemodialysis

Background. We measured middle cerebral artery (MCA) flow velocity(FV), dynamic pressure autoregulation, and carbon dioxide reactivity(CRCO₂) in patients with chronic renal failure before and afterhaemodialysis using transcranial Doppler ultrasonography. Methods. Twelve patients on long-term haemodialysis were recruited.MCA FV was measured continuously. The transient hyperaemic responsetest was used to assess cerebral autoregulation, and per centchange in FV per kPa change in end-tidal carbon dioxide wascalculated to assess CRCO₂. All measurements were recorded beforeand after haemodialysis. Results. MCA FV (mean [SD]) decreased from 57 (10) cm s^–1before to 46 (13) cm s^–1 after haemodialysis (P<0.01).The transient hyperaemic response ratio (THRR) was (mean [SD])1.29 (0.13) before haemodialysis and did not change significantlyfollowing haemodialysis (1.36 [0.10]). CRCO₂ was 21.7 (8.3)%kPa^–1 before haemodialysis and remained unchanged afterwards(20.9 [3.8]% kPa^–1). Values in normal subjects for MCAFV, THRR and CRCO₂ are 56 (12) cm s^–1, 1.26 (0.13) and22 (6)% kPa^–1, respectively. Conclusions. MCA FV decreases significantly after haemodialysis.Dynamic pressure autoregulation and CRCO₂ remain normal in patientswith chronic renal failure, and are not altered significantlyby haemodialysis. Presented at the European Society of Anaesthesiologists AnnualCongress Amsterdam, May 1999.     

Enhancement of Anticorrosive Performance of Cardanol Based Polyurethane Coatings by Incorporating Magnetic Hydroxyapatite Nanoparticles

The present investigation demonstrates renewable cardanol-based polyol for the formulation of nanocomposite polyurethane (PU) coatings. The functional and structural features of cardanol polyol and nanoparticles were studied using FT-IR and 1H NMR spectroscopic techniques. The magnetic hydroxyapatite nanoparticles (MHAPs) were dispersed 1–5% in PU formulations to develop nanocomposite anticorrosive coatings. An increase in the strength of MHAP increased the anticorrosive performance as examined by immersion and electrochemical methods. The nanocomposite PU coatings showed good coating properties, viz., gloss, pencil hardness, flexibility, cross-cut adhesion, and chemical resistance. Additionally, the coatings were also studied for surface morphology, wetting, and thermal properties by scanning electron microscope (SEM), contact angle, and thermogravimetric analysis (TGA), respectively. The hydrophobic nature of PU coatings increased by the addition of MHAP, and an optimum result (105°) was observed in 3% loading. The developed coatings revealed its hydrophobic nature with excellent anticorrosive performance.     

Oral myiasis caused by Musca domestica larvae in a child

Myiasis or infestation of living tissues by Diptera (two winged) fly larvae is primarily a problem of cattle and livestock in tropics. Human infestation is rare, occurs accidentally in persons at extremes of age, who are debilitated or not able to ensure basic hygiene and wound cleanliness. Necrotic tissue in wounds of whatever origin provides ideal substrate for the developing larvae. Depending upon the anatomic sites affected it presents clinically as cutaneous myiasis, myiasis of external orifices (oral, nasal, ocular, aural, anal, genital), and myiasis of internal organs (intestinal, urinary). Cutaneous myiasis is perhaps the most commonly reported entity. Species causing skin, subcutaneous and mucosal myiasis include Gastrophilus intestinalis (horse botfly), Hypoderma bovis (cattle botfly), and Dermatobia homonis (human botfly). Musca domestica, the common house fly, is a rare cause of myiasis despite its presence in abundance.This paper describes oral myiasis in a 16-year-old girl of hypotonic cerebral palsy. She had episodic fever, fetid breath, erythematous, tender and ulcerated swelling over anterior palate from which pus and maggots were coming out. She had lip incompetence and bad orodental hygiene. Radiologic and laboratory investigations revealed no abnormality. The maggots were removed manually and she was treated with orodental hygiene sessions, wound care, antibiotics and nutritional supplements. The larval specimens were identified as early instar of M. domestica. Prevention of human myiasis is important and involves control of fly population, general cleanliness, basic sanitation and health education with a special emphasis on oral health care in patients with special needs.