Effects of electrohydraulic extracorporeal shock wave lithotripsy on submandibular gland in the rat: electron microscopic evaluation

OBJECTIVES: Extracorporeal shockwave lithotripsy (ESWL) has been applied in sialolithiasis as a new treatment modality. The aim of this experimental study is to investigate the local effects of electrohydraulic ESWL applied to the right submandibular gland of the rats. METHODS: This prospective study was conveyed in four groups; groups I, II, III and IV; each group consisting of 20, 20, 18 and 9 rats, respectively, with a randomized distribution. Groups I, II, III and IV received 250, 500, 1000 and 2000 shock waves at 14-16 kV (average 15.1 kV), respectively, to the right submandibular glands on the 0th day. In groups I, II, III, right submandibular glands of the rats were removed on the 0th, 1st, 7th and 15th days; in group IV, this procedure could be managed only on the 0th and 7th days. Light and electron microscopic evaluation were assessed. Using the light microscopic changes, severity of damage score of the glands (SDS) was found. Statistical analysis was done using SDSs. RESULTS: Light and electron microscopic observations have shown that the damage produced by the shock waves were confined to focal areas in the acinar cells (AC), granulated convoluted tubule (GCT) cells and blood vessels at all doses applied. Vacuolization in the cytoplasms of the AC and GCT cells, disintegration of membranes, alteration in the cytoplasmic organization, swelling of the mitochondria and loss of the features were observed on electron microscopy. Increase in the secretion rate; stasis and dilatation in the blood vessels; blebbing and loss of features in the cytoplasm of the endothelial cells were observed. According to the result of the statistical analysis using SDSs; at 250 shock wave dose, a statistically significant difference between the SDSs of the days (0th, 1st, 7th and 15th) was found (P<0.05). The SDS on the 0th day was found to have the lowest value among the other days. And also a statistically significant difference was found on the 0th day between the SDSs at doses of 250, 500, 1000 and 2000 shock waves (P<0.05). The SDS at 250 and 500 shock waves was found to have the lower value than the SDS at the 2000 shock wave. It was observed that produced damage was less prominent by small doses (250, 500 doses) initially (0th day). Electrohydraulic ESWL caused a "patchy type" generalized pathology on submandibular glands of the rats and damaged focal areas were widespread all through the gland from the 1st day on. CONCLUSION: Formation of the damage was concluded to be related to the direct effect of the shock waves rather than the dose used. Electrohydraulic lithotripters are not suitable for sialolithiasis because of the focus problems, local tissue damage and the risk of the damage to the adjacent structures.     

Serum insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 levels in severe iodine deficiency

Iodine deficiency is an important public health problem worldwide. It is well known that it has severe consequences such as brain damage, developmental delay, deficits in hearing and learning and lower intellectual attainment. It also has a negative impact on growth. In this study, we aimed to address this issue and we assessed height standard deviation scores of children living in an area of severe iodine deficiency in comparison to those living in a mild iodine deficiency area. Serum levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), thyroxine (T4), and thyroid stimulating hormone (TSH) were also analyzed to investigate the mechanisms by which iodine depletion leads to growth failure. Pubertal children in a severe iodine deficient SID area had lower height standard deviation scores (HSDS), IGF-I and IGFBP-3 levels than those living in mild iodine deficient MID area. Similar findings could not be elucidated in the prepubertal age group. The major determinants of HSDS were age, IGF-I, IGFBP-3 and TSH. IGF-I and IGFBP-3 were negatively correlated with T4. These findings suggest that iodine deficiency has a negative impact on growth, as well as IGF-I and IGFBP-3 levels. This effect seems to be due to the derangements in thyroid hormone economy arising from iodine depletion. The degree of this impact may be related to the duration of iodine depletion or may be dependent on the developmental stage of the organism at the time of iodine depletion.     

Malignant pleural mesothelioma in a child: long-term survival with ICE-WAC chemotherapy regimen

Malignant mesothelioma is a very rare tumor in childhood. Presently, treatment of this disease continues to be frustrating and prognosis remains poor. We here report a pediatric case of malignant pleural mesothelioma who gave a complete response to ICE-VAC chemotherapy regimen and achieved a long-term survival. An eight-year-old girl underwent exploratory thoracotomy and decortication because of a unilateral loculated and multicystic pleural effusion. Histopathological diagnosis was sarcomatoid pleural malignant mesothelioma. After decortication, chemotherapy with ICE (ifosfamide, carboplatin, etoposide) - VAC (vincristine, adriamycin, cyclophosphamide) combination was started. Six courses of chemotherapy resulted in complete clinical and radiological tumor response. She did not receive any further therapy and remains disease-free three years after the first remission. ICE-VAC chemotherapy combination resulted in a complete tumor response and a long-term disease-free survival for the presented case. The efficacy of this chemotherapy regimen in malignant mesothelioma needs to be documented in future trials.     

Tensile strength of type IV dental stones dried in a microwave oven

STATEMENT OF PROBLEM: It is known that drying dental stones in a microwave oven can save time, but the strength of the material may be affected by different drying methods. PURPOSE: This study evaluated the diametral tensile strength (DTS) of 5 type IV gypsum products at different time intervals using microwave and air-drying methods. MATERIAL AND METHOD:. A total of 300 cylinder specimens were prepared from 5 type IV dental stones (Moldano, Amberok, Herastone, Shera-Sockel, and Fujirock; n = 60 per stone) in accordance with the manufacturers' recommendations. Half of the specimens of each stone (n = 30) were dried in open air within a temperature range of 20 +/- 2 degrees C; the other half (n = 30) underwent initial setting in a silicone rubber mold in open air for 10 minutes and then were dried in a microwave oven for 10 minutes. Within these groups, 10 specimens were tested under diametral compression at each of the following time periods: 30, 60, and 120 minutes after drying. Three-way analysis of variance and Scheffe's post hoc test were performed for statistical comparisons at a significance level of P<.05. RESULTS: At all time intervals, the diametral tensile strength values for dental stones dried in a microwave oven (mean 2.99 MPa) were significantly higher (P<.01) than the values for specimens dried in open air (mean 2.53 MPa). CONCLUSION: Within the limitations of this study, microwave oven drying had a positive effect on the diametral tensile strength of 5 type IV dental stones.     

The effects of tonsillectomy and adenoidectomy on serum IGF-I and IGFBP3 levels in children

OBJECTIVE: Obstructive adenoid and tonsillar hyperplasia may present with retardation of growth. Interruption of growth hormone-insulin-like growth factor I axis resulting from abnormal nocturnal growth hormone secretion is among the postulated causes. Growth hormone (GH) mediates its anabolic effects on tissues through insulin-like growth factor I (IGF-I). Most of the circulating IGF-I is bound to insulin-like growth factor binding protein 3 (IGFBP3). The objective of this study is to determine blood serum levels of IGF-I and IGFBP3 in patients with adenoid and tonsillar hypertrophy. Furthermore, we want to investigate the effect of tonsillectomy and adenoidectomy (T&A) on these levels. STUDY DESIGN: The blood serum levels of IGF-I and its binding protein IGFBP3 were examined in 41 randomly selected children with a diagnosis of upper airway obstruction resulting from hypertrophic tonsils and adenoids. METHODS: Blood samples were taken preoperatively and repeated at 3 to 6 months (mean, 4.3 mo) following T&A operation. Coated-tube immunoradiometric assay (IRMA) method was used to analyze IGF-I and IGFBP3 levels. RESULTS: Thirty-two of 41 children were eligible for the analysis. When the preoperative and postoperative results were compared, it was found that there was a statistically significant increase in serum IGF-I and IGFBP3 levels in these 32 children (P <.001). In 7 of the 32 patients, the preoperative serum IGF-I levels were below normal. Postoperatively these levels increased within normal range. This was also statistically significant (P = .016). CONCLUSION: These findings revealed that obstructive adenoid and tonsillar hypertrophy may cause decreased serum IGF-I levels by affecting the GH-IGF-I axis, and T&A is an effective therapeutic measure in these patients.     

Monitoring of DNA damage in foundry and pottery workers exposed to silica by the alkaline comet assay

BACKGROUND: Workers in foundry and pottery are exposed to a mixture of chemicals and silica, which is suspected to cause genetic alterations. METHODS: To investigate the potential hazard associated with the occupational exposure to silica, DNA damage in the peripheral lymphocytes of 30 foundry and 22 pottery workers were examined by the alkaline single-cell gel electrophoresis or Comet Assay, and compared to 52 healthy subjects with no history of occupational silica or chemical exposure. RESULTS: The DNA damage observed in the lymphocytes of both foundry and pottery workers was significantly higher than that in their controls. Cigarette smoking was also related to DNA damage since the DNA damage observed in smoking silica-exposed workers compared with the non-smoking workers was significantly higher. CONCLUSIONS: Occupational exposure of silica from foundry and pottery workplaces has been associated with the increased DNA damage and smoking which represents an additional risk factor and must be avoided.     

p53 gene mutations are rare in human papillomavirus-associated colon cancer

Recent studies suggest that infection with high risk human papillomavirus (HPV) is a common event in colon tumors. Infection by oncogenic HPV may result in functional inactivation of the p53 protein in absence of mutations. Thus far no studies have been made to examine the frequency of p53 mutations in HPV-associated colon cancer. The purpose of this study was to investigate the interrelationship between p53 mutations and HPV infection. The 'hot-spot' region of the p53 gene for mutations was analyzed by PCR-SSCP and direct sequencing in HPV-positive tumor samples. Only 2 mutations were identified in 56 samples. This rate was much lower than reported for sporadic colon tumors. Our results indicate an inverse relationship between p53 mutations and HPV infection and suggest that p53 inactivation caused by HPV infection may play a role in the pathogenesis of colon cancer.     

P53 codon 72 polymorphism in breast cancer

Increased and deregulated proliferative activity due to abnormalities in the cell cycle modulators are frequently observed in cancer. A sequence polymorphism at codon 72 of the p53 gene results in either a proline or an arginine and may induce different functional activities. This polymorphism has been shown to have varying ethnic and geographical distribution. It has been reported that the p53 Arg homozygous genotype could be a potential genetic risk factor for cancer. However, not all investigations have been consistent and this hypothesized association remains controversial. The purpose of this study was to investigate the genotype frequencies and association of the p53 codon 72 polymorphism with breast cancer in Turkish patients. A group of 115 patients with breast cancer and a control group of 76 healthy individuals were enrolled in the study. A significantly higher prevalence of homozygosity for the p53 Arg allele was observed in the patients as compared to the controls. Statistical analysis suggested a strong association between the Arg/Arg genotype and breast cancer.     

Inverted Meckel's diverticulum as a cause of obscure lower gastrointestinal bleeding

Inverted Meckel's diverticulum is an infrequent cause of gastrointestinal blood loss, especially in adults. A high index of suspicion is needed for this rare entity when entertaining the possible differentials of gastrointestinal bleeding.