The effect of photodynamic therapy on the salivary flow rate, IgA concentration and C-reactive protein levels in active smokers: a case-control study

OBJECTIVE

This study aimed to evaluate the effect of photodynamic therapy (PDT) on the salivary flow rate, secretory immunoglobulin A, and C-reactive protein levels in active smokers.

PATIENTS AND METHODS

The present study is a prospective case-control study. Twenty active smokers were allocated to two groups randomly of ten participants each: the experimental group was irradiated while the control was exposed to sham irradiation by turning off the equipment. In the experimental group, methylene blue mediated PDT was applied both intra- and extra-orally over the major and minor salivary glands using a diode laser. 780 nm wavelength and 4 J/cm2 of energy were used to irradiate the 10 points of major salivary glands (6 for parotid and 2 for submandibular glands and 2 for sublingual glands). On the other hand, 660 nm was used to apply 10 J/cm2 of energy over the minor salivary glands at numerous points. The samples of the stimulated and unstimulated saliva were collected from both groups to assess the SFR. ELISA method was used to assess the level of salivary IgA levels, statistical analysis was done using a one-way ANOVA, and a p-value of <0.05 was considered significant.

RESULTS

The results showed a significant increment in salivary and secretory immunoglobulin A levels of subjects undergone photodynamic therapy. C-reactive protein levels were significantly decreased in subjects exposed to irradiation.

CONCLUSIONS

The present study concludes that photodynamic therapy significantly improves the salivary flow rate, secretory Immunoglobulin A, and oral health quality of life in smokers. The inflammatory salivary marker C-reactive protein, which is usually raised in smokers, is also reduced.

Changes in essential salivary parameters in patients undergoing fixed orthodontic treatment: A longitudinal study

Objective

Orthodontic treatment using fixed appliances is known to alter the oral environment and encourage plaque retention around orthodontic brackets and bands, resulting in enamel demineralization and gingival inflammation. This study aimed to evaluate the changes in essential salivary parameters in patients undergoing fixed orthodontic treatment.

Materials and Methods

Saliva samples were collected from 60 patients before and 2 months after commencing fixed orthodontic treatment. The salivary flow rate, pH, buffering capacity, and levels of amylase, total protein, and glucose were determined. Parametric and nonparametric tests for paired samples were used for comparing the mean differences before and after commencing treatment.

Results

Significant reductions in the salivary flow rate, pH, and buffering capacity were noted 2 months after commencing treatment (P < 0.05). Total protein concentrations and calcium levels decreased significantly and amylase and glucose levels increased after commencing treatment (P < 0.05). Significant correlations were observed between salivary total protein concentrations and buffering capacity as well as calcium levels (P < 0.05).

Conclusion

These findings indicate that the biochemical properties of saliva are altered after introducing fixed orthodontic appliances into the oral cavity, thereby promoting plaque retention and increasing the susceptibility to tooth demineralization and gingival inflammation.

An outbreak of lymphadenitis associated with Stenotrophomonas (Xanthomonas) maltophilia in Omani goats

Stenotrophomonas maltophilia is a commonly isolated organism from human clinical specimens and is gaining significance as a pathogen in immunocompromised patients and nosocomial infections. In most cases it is difficult to establish the source of human infections. In veterinary medicine, S. maltophilia is not generally considered a primary pathogen. In the present study, we report the occurrence of 16 cases of caprine abscess from which S. maltophilia was isolated in pure culture from 15 animals. In six animals, the abscesses were confined to the pre-scapular lymph nodes but in the remaining nine, the cutaneous abscesses were multiple and extended from the neck to the inguinal area. The possibility is suggested that goats in Oman, which often live in close proximity to humans, might potentially serve as a reservoir of infection.

Hepatic lipidosis associated with cobalt deficiency in Omani goats

Livers from 36 of 684 (5.3%) apparently healthy goats examined at an abattoir in the greater Muscat area of Oman exhibited gross pathological findings characterized by extremely pale, friable, fatty livers encompassing the entire organ. Histopathologically, diffuse hepatic lipidosis and occasional bile duct proliferation were observed. Periodic acid Schiff-positive, diastase-resistant pigment was observed in the macrophages lining the sinusoids. These histopathological lesions were consistent with those characteristic of ovine white liver disease. Cobalt analysis revealed that normal livers had six times more cobalt and a 3-fold less fat content than those measured in the fatty livers. This is the first report of an association between cobalt deficiency and hepatic lipidosis in Omani goats.

Exencephaly and axial skeletal malformations induced by maternal administration of sodium valproate in the MF1 mouse

Clinical and epidemiological studies indicate that maternal use of valproic acid (VPA) during pregnancy causes an increased risk for spina bifida in the fetus. A proportion of infants exposed to VPA in utero exhibit a characteristic pattern of facial malformations. Despite the developmental interdependence of the neural plate and paraxial mesoderm during normal morphogenesis, the possible involvement of the axial skeleton in VPA-induced NTD has not been clearly documented. So the objective of this investigation was to determine the nature and extent of involvement of the axial skeleton in VPA-induced exencephaly in the mouse. A single dose of 600 mg/kg of sodium valproate was administered (IP) to MF1 mouse on day 8 of gestation. This treatment resulted in significant increase in resorption, reduction in mean fetal weight, and exencephaly (25%) of live fetuses. Several craniofacial malformations and subcutaneous haematomas were associated with exencephaly. Alizarin red-stained skeletal preparations revealed maxillary-, mandibular hypoplasia, absence of skull vault, hypoplasia and/or agenesis of basicranial bones, and obtuse angulation of the craniovertebral junction. Hemivertebrae, longitudinal fusion of the vertebral arches and bodies, accessory ribs (cervical and lumbar), fusion of thoracic ribs, and several patterns of sternal variations were observed. Nonexencephalic VPA-treated embryos exhibited mandibular, maxillary hypoplasia, arched and cleft palates, cleft lip, kinky tail, and vertebral and sternal anomalies. Treated embryos at early stages of development revealed delay in elevation and fusion of neural folds, distended IVth ventricle, kinky spinal cord, incomplete separation of somites and growth retardation. When viewed in light of the published work on VPA action on embryonic systems, these observations suggest that abnormalities associated with VPA-induced exencephaly may be due to either a direct action of VPA on the precursors of these organs or secondary to its action on neural tube. A significantly high incidence of NTD and their consistent association with defective development of the axial skeleton suggest that this is an excellent experimental model for investigating the pathogenetic mechanism(s) of VPA induced NTD.

Characteristics of the limb malformations induced by maternal exposure to cadmium in the mouse

Single doses of 2,3,4,6,8,10, and 15 mg/kg of cadmium chloride were administered (SC) to groups of MF1 mice on one of days 7 to 12 of gestation. Fetuses collected on day 18 were observed for limb malformations, and alizarin red-S stained skeletons were examined for their skeletal bases. Ectrodactyly, postaxial polydactyly, syndactyly, brachydactyly, adactyly, phocomelia, meromelia, and malrotation of the limbs were detected in a significant number of fetuses. Days 7 to 10 were greatly susceptible for induction of these malformations. Postaxial ectrodactyly was more frequent in the forepaws, and sidedness was not significant. Preaxial ectrodactyly preferentially affected the left hindpaws in the 9th-day treatment group. Postaxial polydactyly was predominently right sided and mostly involved the forepaws. Day 8 was particularly susceptible for induction of adactyly. Malrotation of the limbs together with edema and caudal narrowing resulted in a 'penguin-like' appearance. Ossification of the long bones, the carpals, tarsals, and phalanges were affected. Even those limbs that were not externally malformed had skeletal dysgenesis. Limb buds examined histologically at midgestation showed scanty and poorly organized mesenchyme, extensive elaboration of marginal sinsus, reduced thickness of the apical ectodermal ridge (AER), and discontinuous basement membrane. It is speculated that such histologic alterations at early stages of development could have contributed to the defective morphogenesis of limbs in this animal model.

Effects of acute doses of ethanol administered at pre-implantation stages on fetal development in the mouse

The objective of the present study was to investigate the effects of maternal administration of acute doses of alcohol at preimplantation stages of pregnancy on the fetus and fetal membranes. Single doses of 0.02 ml and 0.03 ml/g body wt. of 25% v/v of absolute alcohol in saline were administered to groups of MF1 mice on one of days 1-6 of gestation. Controls were either pair-fed and pair-watered or saline-treated. Fetuses and placentae were collected on day 15. Resorption and fetal death were increased in most of the alcohol treatment groups. The reduction in fetal body weight was significant in the 0.03 ml group. Compared to the saline controls, most experimental groups exhibited a rise in placental weight. The reduction in cord length was significant in comparison to untreated controls. Craniofacial and systemic abnormalities appeared to correlate with retardation of fetal growth. Hence, following treatment of 0.03 ml/g body wt. of alcohol solution on days 2 and 6, fetuses were collected on days 14, 16 and 18. Most fetuses were found to recover gradually from anomalies associated with growth retardation but the 'catch up' growth was not adequate enough to compensate for the reduction in body weight. These observations indicate that the pre-implantation stage of mouse embryo development is susceptible to the deleterious effects (fetal death and intrauterine growth retardation) of acute doses of alcohol.

Malformations of the axial skeleton in cranioschisis aperta and exencephaly in rat fetuses induced after neural tube closure

Single doses of cyclophosphamide were administered (IP) to groups of Wistar rats, on different days of gestation after neural tube closure (days 12-15) and fetuses were collected on day 20. A very large number of the fetuses treated during days 12-14 exhibited cranioschisis and exencephaly. Ethanol fixed, alizarin red stained specimens were observed for axial skeletal abnormalities. The exencephalic ones lacked ossified skulls. The basicranial bones were either under ossified or had undergone extensive fusion resulting in reduction in cranial volume. The basicraniovertebral angle was obtuse. The vertebral bodies and arches showed varying degrees of hypoplasia, fusion and/or agenesis. The development of ribs and sternebrae was also extensively affected. Treatment on day 15 did not induce exencephaly but the axial skeleton was hypoplastic. Wavy ribs were a remarkable feature of these fetuses. All exencephalic fetuses had subcutaneous haemorrhages; many of them were obviously oedematous. These data indicate that the susceptible period for induction of these anomalies does not stop at neuropore closure.

Effects of acute doses of ethanol on pre- and postnatal development in the mouse

Investigators on fetal alcohol syndrome (FAS) both clinical and experimental, have generally concentrated attention on chronic alcoholism. In an attempt to elucidate the effects of binge drinking on pre- and postnatal development, single doses of 0.01, 0.02 and 0.03 ml/g body weight of alcohol solutions (25% v/v of ethanol in saline) were administered intraperitoneally to groups of mice on days 8-12 of gestation. Controls were untreated or starved for 6 h. Fetuses collected on day 18 revealed retardation, fetal mortality and craniofacial and digital malformations. While growth retardation and fetal mortality were dose-dependent, malformations were stage-dependent. The 0.01-ml group exhibited only postaxial polydactyly of the forepaw. The reduction in fetal weight of 0.03-ml groups corresponded well with that of umbilical cord length. Following administration of single doses of 0.01 ml/g of ethanol solution on days 8-12, groups of mice were allowed to deliver. Controls were untreated or pairfed and pair watered. Pups were reared by the respective mothers and their survival and growth were observed till postconception day 71 and thereafter brother/sister matings were carried out. At least one pup in each litter remained extremely stunted and failed to reproduce. No significant differences in mortality, growth rates and reproductive capacity of the rest of the pups were observed. It is concluded that single but heavy doses of ethanol during organogenesis leads to a situation reminiscent of human FAS.