Changes in structure and function of bacterial communities during coconut leaf vermicomposting.

To understand bacterial community dynamics during the vermicomposting of lignin-rich coconut leaves using an indigenous isolate of an epigeic earthworm, Eudrilus sp., we employed amplicon-based pyrosequencing of the V1 to V3 region of the 16S rRNA genes. Total community DNA was isolated from two separate vermicomposting tanks in triplicate at four different stages of the process: pre-decomposition (15th day), initial vermicomposting (45th day), 50-70% vermicomposting (75th day) and mature vermicompost (105th day). Alpha diversity measurements revealed an increase in bacterial diversity till the 75th day, which then declined in the mature vermicompost. Beta diversity comparisons showed formation of distinct, stage-specific communities. In terms of relative abundance, the Acidobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes, Nitrospirae, Planctomycetes, TM7 and WS3 groups increased until the 50-70% vermicomposting stage (p = 0.05). During the same time, the abundance of Bacteroidetes and Proteobacteria decreased. In contrast, the levels of Firmicutes increased throughout the 105-day vermicomposting process. The distribution of the most abundant OTUs revealed that each stage of the vermicomposting process possessed its own unique microbiome. Predictions based on the OTUs present by PICRUSt suggested a functional shift in the microbiome during vermicomposting. Enzymes and pathways of lipid and lignin metabolism were predicted to be initially abundant, but by the end of the process, biosynthesis of secondary metabolites and plant beneficial properties were enriched. The study revealed that bacterial communities undergo a continuous change throughout the vermicomposting process and that certain OTUs associated with specific stages could be targets for further improvements in the process.

Human papillomavirus and oral disease - emerging evidence: a review.

Human papillomavirus (HPV) infections have received considerable attention in recent years. Of the 120 or so known types of the virus, some cause a variety of benign wart-like lesions of the skin and genital and oral mucosae, whilst others are aetiologically associated with cervical and anogenital cancers. Recent epidemiologic evidence suggests that HPV may also be an independent risk factor for oropharyngeal cancer. In this context it has been suggested that HPV virus may modulate the process of carcinogenesis in some tobacco and alcohol induced oropharyngeal cancers and act as the primary oncogenic agent for inducing carcinogenesis among non-smokers. Dental practitioners have a major role in detecting all lesions of the oral mucosa caused, or possibly caused, by HPV. This paper briefly reviews the current state of knowledge of molecular and clinical aspects of HPV infections of the oral mucosa.

Squamous differentiation in a sarcomatoid chromophobe renal cell carcinoma: an unusual case report with review of the literature.

We describe an extremely rare occurrence of a squamous differentiation in a sarcomatoid chromophobe renal cell carcinoma in a 45-year-old woman with nodal and lung metastasis at presentation. The tumor on histology showed all 3 components intimately admixed with each other, which to the best of our knowledge is the first such case to be reported in the literature. The renal pelvis was smooth walled and uninvolved. Kidney-specific cadherin was positive in the chromophobe renal cell carcinoma areas and negative in the sarcomatoid and squamous areas.

Diagnostic approaches to common oral symptoms

In routine dental practice patients seek oral care for various reasons. Some of these reasons are pain, swelling and ulcers. This chapter will deal with various aspects involved in evaluating the above listed symptoms AU)

Orofacial pain

Orofacial pain is one of the most common reasons why many persons seek dental consultation. Because of the complex nature of the problem, patients with orofacial pain present a real diagnostic and theraputic challenge to the practitioner. Orofacial pain results from noxious stimulation of free nerve endings in orofacial tissues. The peripheral nerve endings act as nociceptors (pain receptors) detect and convey the noxious information to the brain, where pain is perceived. Although in a majority of patients the orofacial pain is of odontogenic origin (such as the sequel of dental caries or trauma to the tooth), non-odontogenic source of pain is also frequent in clinical practice (AU)

White lesions of the oral mucosa

A simple definition of a mucosal white lesion would be "a lesion which appears clinically whiter than the surrounding mucosa." Mucosal white lesions are to be taken seriously because a small proportion of these are known to possess malignant potential which often pose a diagnostic challenge even to an experienced clinician. Differentiation between white lesions with a potential is therefore of paramount importance. When in doubt, the clinician should always perform a biopsy of the lesion and seek a histopathologic report (AU)

Red lesions of the oral mucosa

Oral soft tissue lesions, which clinically appear red, are common. These lesions may present themselves in different clinical forms. They may be patchy, spotted, macular, papular, nodular, localized, diffuse, single, multiple and so on. Lesions that appear red may be considered primary when they appear when they appear as a result of local causes. They are secondary when their occurence is a result of systemic pathology. It is not uncommon that red lesions may be associated with pigmented or white lesions. In this chapter, commonly encountered red lesions of the oral mucosa are briefly discussed (AU)

Ulcerative and erosive lesions of the oral mucosa

A mucosal ulcer is a breach in the epithelial continuity that results in the exposure of underlying connective tissue to the external environment. Mucosal erosion, on the other hand, is a shallow depression resulting from the loss of a few layers of epithelial cells. In erosive lesions the connective tissue is not exposed to the external environment. In dental practice oral mucosal ulcers and erosions are commonly encountered. Most ulcerative and a few erosive lesions are symptomatic and patients seek consultation for relief from discomfort and pain. Oral ulceration and erosion can result from several causes which may operate at local or systemic levels. Diagnosis of oral ulcerative and erosive lesions is not easy. This is because of the fact that ulcers, in particular, may often look clinically similar regardless of the differences in their causative factors. Some ulcers may also possess malignant potential or frank malignant features at the time of patient's first visit (AU)

Vesiculo-bullous lesions of the oral mucosa

Oral mucosa frequently manifests a variety of lesions that are fluid-filled and raised. When such lesions are ovoid and about 0.5 cm, these are generally referred to as bullae (AU)

Anaemias of oral significance

Anaemia is not a disease in itself. It is a sign of a single or multiple diseases. Anaemia is said to exist when the haemoglobin concentration is below normal for the age and sex of an individual. The synthesis and normal circulatory level of haemoglobin in any given individual depend on factors such as an adequate supply of haemopoietic nutrients, normal functioning of bone marrow, and proper utilization of haemoglobin. Based on these factors anemia can be broadly grouped into three categories: 1. Anaemia due to lack of haemopoietic nutrients (nutritional anemia) 2. Anaemia due to bone marrow dysfunction (aplastic anaemia) 3. Anaemia due to excessive breakdown of red blood cells (haemolytic anaemia) (AU)

Oral diseases of immunological background

From a clinician's point of view, diseases of the immune system are broadly grouped into the following categories: I. Immunodeficiency disorders II.Autoimmune diseases III. Hypersensitivity reactions (AU)

Bleeding disorders

The primary objective of this chapter is to deal with the most important bleeding disorders from a dental point of view. An understanding of the disorders discussed in this section hinges upon a basic knowledge of the various physiological processes involved in normal haemostasis (AU)

Histological spectrum of lymphoid follicles and aggregates in Helicobacter pylori gastritis.

Seventy three patients of non ulcer dyspepsia underwent upper gastrointestinal endoscopy with biopsy from antrum and body of stomach. The tissue was stained with hematoxylin eosin and warthin starry stain. The severity of gastritis was correlated with the presence of Helicobacter pylori and lymphoid follicles and aggregates. The incidence of chronic atrophic gastritis and Helicobacter pylori were found to be 97% and 64.1% respectively. Lymphoid follicles and aggregates were seen in 32.9% of chronic atrophic gastritis. Severity of gastritis with activity correlates with Helicobacter pylori colonisation and the presence of lymphoid follicles and aggregates. We have found that there is no difference between presence of lymphoid follicles and aggregates in Helicobacter pylori positive and negative gastritis. The development of lymphoid follicles probably represents an immune response to the colonisation of gastric mucosa by Helicobacter pylori.

Role of Helicobacter pylori in gastric carcinoma.

BACKGROUND: Helicobacter pylori infection has recently been incriminated in the pathogenesis of gastric carcinoma and chronic atrophic gastritis and intestinal metaplasia are considered to be precursors of this condition. Although the incidence of Helicobacter pylori infection in India is high that of gastric carcinoma is low. We, therefore, decided to examine the association between Helicobacter pylori, intestinal metaplasia and gastric carcinoma in a prospective study. METHODS: Fifty patients with carcinoma of the stomach and 50 with non-ulcer dyspepsia underwent upper gastro-intestinal endoscopy and had biopsies from the antrum, body and carcinomatous tissue. In 12 cases of gastric carcinoma, tissue was obtained from resected specimens at operation. The types of gastritis, intestinal metaplasia and presence of Helicobacter pylori were assessed by staining with haematoxylin and eosin, periodic acid-Schiff reagent with alcian blue and Warthin-Starry stains. RESULTS: The incidence of chronic atrophic gastritis, intestinal metaplasia and Helicobacter pylori were 82%, 36% and 38% in patients with carcinoma and 86%, 4% and 68% in those with non-ulcer dyspepsia. Helicobacter pylori positivity was significantly higher (p < 0.05) and intestinal metaplasia significantly lower (p < 0.001) in patients with non-ulcer dyspepsia than in those with carcinoma. Of the 50 cases with carcinoma, 28 were of the intestinal and 22 of the diffuse type. The incidence of chronic atrophic gastritis, intestinal metaplasia and Helicobacter pylori in the intestinal type of carcinoma was 71%, 46% and 39% while in the diffuse type it was 32%, 23% and 36%. The incidence of Helicobacter pylori infection did not differ significantly in the two types of carcinoma. CONCLUSIONS: We have found that although Helicobacter pylori infection and chronic atrophic gastritis are common in Indians, the incidence of intestinal metaplasia is low. Helicobacter pylori infection was equally common in both the intestinal and diffuse type of gastric carcinomas. Our findings, therefore, cast doubt on the role of Helicobacter pylori infection in gastric carcinogenesis.

Tuberculous abscess of the liver associated with HIV infection.

Tuberculosis is an AIDS-defining illness in HIV-seropositive patients. Though disseminated tuberculosis is common in HIV-seropositive patients, hepatic involvement in the form of abscess formation is rare. We report such a patient.

Fibrosing necrotic nodule of the liver.

A fibrosing necrotic nodule of the liver is described in a 35 year old man suffering from malaria. This non-tumorous lesion is considered to be an entity of diverse pathogenesis.

Clinicopathologic study of fallopian tube closure after single transcervical insertion of quinacrine pellets.

OBJECTIVE: To determine the effect on tubal closure of intrauterine quinacrine by dose and time from administration. DESIGN AND PARTICIPANTS: Subjects included 33 women of reproductive age who were awaiting hysterectomy for nonmalignant conditions at a Bombay, India medical college. Ten women received 252 mg quinacrine as pellets using a modified Copper-T IUD inserter followed by hysterectomy within 6 weeks, and 23 women received 324 mg quinacrine followed by hysterectomy 6 to 20 weeks post-insertion. Hysterosalpingograms were done before insertion, prior to surgery and on the fresh surgical specimen. The uteri and tubes were subjected to histology studies, including grading of tubal damage. For study of dose, an additional 7 women receiving 100 mg quinacrine (and previously reported) were included. MAIN OUTCOME MEASURE: Tubal closure rates by hysterosalpingogram and tubal histology. RESULTS AND CONCLUSION: Tubal closures were directly related to quinacrine dose and length of insertion-hysterectomy interval. For the 252 mg quinacrine dose, 55.0% of intramural tubal segments and 5.9% of isthmic segments showed histologic evidence of closure. For the 324 mg dose, all intramural tubal segments and 58.8% of isthmic segments showed histologic evidence of closure. Clinical conditions, such as dysfunctional uterine bleeding, were associated with lower tubal closure rates. Multivariate discriminant analysis showed quinacrine dose to be more important than quinacrine-hysterectomy interval.

PIP: At B.Y.L. Nair Hospital in Bombay, India, physicians compared data on 10 women who had received 252 mg quinacrine in pellet form transcervically followed by a total hysterectomy within 6 weeks of quinacrine insertion with data on 23 women who had received 324 mg quinacrine in pellet form transcervically followed by a total hysterectomy 6-20 weeks after insertion. All the women were already scheduled for a hysterectomy for nonmalignant conditions. The researchers also included data on seven other women who had received 100 mg quinacrine earlier. They wanted to examine the effect on tubal occlusion of intrauterine quinacrine by dose and time. They conducted hysterosalpinograms before insertion, prior to hysterectomy, and on the fresh surgical specimens of the tubes and uterus. Women receiving the 324 mg dose had a much higher tubal closure rate than those receiving a 252 mg dose (100% vs. 50%; p = 0.01). With the 325 mg dose, all intramural tubal segments and 58.8% of isthmic segments had histologic stage II or III closure. With the 252 mg dose, 55% of intramural tubal segments and 5.9% of isthmic segments had stage III closure. A quinacrine-hysterectomy interval of at least seven weeks resulted in a better tubal closure rate than that of less than seven weeks (22/24 vs. 9/16; p = 0.01). Clinical conditions (pooled data; myomas, dysfunctional uterine bleeding, cervical intraepithelial neoplasia, and prolapse) were positively associated with tubal closure (31/40 vs. 9/40; p = 0.02). Quinacrine dose had a more significant effect on tubal closure than quinacrine-hysterectomy interval (standard discriminant function coefficient, 0.55 vs. 0.35).

Helicobacter pylori in normal gastric mucosa.

Since the discovery of Helicobacter pylori (H. pylori) in 1983 several studies have established relationship of H. pylori with gastritis, duodenal ulcer disease and gastric carcinoma. H. pylori infection is widely prevalent and exposure occurs at younger age in our country. Several Western studies have shown prevalence of H. pylori in normal gastric mucosa to range from 0-25%. As similar information is not available from our country we estimated the prevalence of H. pylori in histologically normal gastric mucosa. Of the 50 asymptomatic volunteers studied, 33 showed histological evidence of gastritis and 28 of these were H. pylori. We conclude that histological gastritis is very common in young asymptomatic Indians and H. pylori infection is noticed in almost 25% subjects with histologically normal gastric mucosa.