Recurrent Cervical Abscess Due to Pyriform Sinus Fistula-A Case Report

The pyriform sinus fistula is rare congenital anomaly of either third or fourth branchial pouch, which most frequently presented itself by recurrent episodes of neck abscess for long time. Majority of patients with this anomaly presented with symptoms before 10 years and it is more common than has previously been commonly found on leftside (93%). Clinically high index of suspicion, cannulation of the tract under general anaesthesia, Direct laryngoscopy and fistulogram have freequently been successful in identifying the presence of these embryological remnants. Surgical exploration of sinus tract with its total excision, guided with cannula inside its lumen is the definitive treatment.     

Multiple intramedullary lipomas with conal intramedullary dermoid: magnetic resonance appearances.

BACKGROUND CONTEXT: Intramedullary fat-containing benign childhood tumors of the cord include lipomas, dermoid cysts, and teratomas. These are embryonal tumors. Most intramedullary fat-containing tumors are solitary. Multiple intramedullary lipomas are rare and may represent a spinal lipomatous malformation. The presence of another intramedullary dermoid tumor in the same case is rare. PURPOSE: The intent of this case report is to look at magnetic resonance features and possible mechanisms of association of these fat-containing intramedullary tumors. STUDY DESIGN/SETTING: A 3-year-old male child presented with spastic quadriplegia. METHODS: Magnetic resonance imaging (MRI) of spine was done on a 1.5-T scanner in different planes. RESULTS: MRI showed multiple intramedullary spinal lipomas with an intramedullary dermoid involving the conus, cord atrophy, and subarachnoid fat droplets. CONCLUSION: Multiple intramedullary lipomas with an intramedullary dermoid represent a form of spinal lipomatous malformation. Both may represent embryogenic mesenchymal inclusions and hamartomatous growth, which can be accurately diagnosed with MRI.     

HIV seroincidence among patients at clinics for sexually transmitted diseases in nine cities in the United States

Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics.     

Receptor-Mediated Choreography of Life and Death

The cytokine tumor necrosis factor was originally identified as a protein that kills tumor cells. So far, 18 distinct members of this family have been identified. All of them regulate cell survival, proliferation, differentiation, and cell death, also called apoptosis. The apoptosis induced by TNF, and other members of the family, for example, FasL, VEGI, and TRAIL is mediated through death receptors. The apoptotic signals by these cytokines are transduced by eight different death domain- (DD) containing receptors (TNFR1, also called DR1; Fas, also called DR2; DR3, DR4, DR5, DR6, NGFR, and EDAR). The intracellular portion of all these receptors contains a region approximately 80 amino acids long referred to as the death domain. Upon activation by its ligand, the DD recruits various proteins that mediate both death and proliferation of the cells. These proteins in turn recruit other proteins via their DDs or death effector domains. The actual destruction of the cell, however, is accomplished by serial activation of a family of proteases referred to as caspases. Cell death is negatively regulated by a family of proteins that includes decoy receptors, silencer of DD, sentrin, cellular FLICE inhibitory protein, cellular inhibitors of apoptosis, and survivin. This review is an attempt to describe how these negative and positive players of cell death perform a harmonious dance with each other.     

Elevated levels of homologous DNA recombination activity in the regenerating rat liver

We have characterized homologous DNA recombination activity in nuclear protein extracts prepared from quiescent and regenerating rat livers. Activity measured in regenerating liver extracts was elevated approximately 35-fold above control, and its appearance closely mirrored the first wave of DNA synthesis, peaking 24 hours after a regenerative stimulus, and returning fairly rapidly to basal levels. We also identified a strand-transferase protein of approximately 100 kDa whose presence in these extracts correlates with homologous recombination activity. Recent evidence suggests that mammalian somatic cells possess a recombinational DNA repair mechanism analogous to that described in the yeastSaccharomyces cerevisiae. Our results indicate that this recombinational repair process may be regulated in vivo by, or play a role in, progression through the cell division cycle.     

Polyclonal anti-PSA is more sensitive but less specific than monoclonal anti-PSA: Implications for diagnostic prostatic pathology

Prostate-specific antigen (PSA) production by nonprostatic tissues has been reported, casting doubts on its specificity. The immunohistochemical relative specificity and sensitivity of PSA expression using monoclonal and polyclonal anti-PSA was analyzed on 60 prostate carcinomas, 40 normal seminal vesicles, and 310 nonprostatic tumors. All nonprostatic tumors proved negative with both antibodies. However, 13 (32%) seminal vesicles showed immunoreactivity with polyclonal anti-PSA, but none showed immunoreactivity with the monoclonal antibody. The sensitivity of the 2 antibodies for prostate cancer varied with tumor grade. In Gleason pattern 3, both antibodies showed diffuse immunostaining in all cases. In Gleason pattern 5, polyclonal anti-PSA showed diffuse (>95%) tumor cell positivity in 18 cases (90%), while with the monoclonal antibody, 7 cases (35%) showed only focal (<10%) tumor cell immunoreactivity. Thus, monoclonal anti-PSA seems to be useful in small gland proliferations in which the differential diagnosis includes seminal vesicle, while for poorly differentiated neoplasms, polyclonal anti-PSA is considered superior. Sections of high-grade prostate cancer should be included as positive controls for PSA immunostaining.     

Monoclonal small (well-differentiated) lymphocytic proliferations of the gastrointestinal tract resembling lymphoid hyperplasia: A neoplasm of uncertain malignant potential

Three histologically benign-appearing or diagnostically equivocal small lymphocytic proliferations of the gastrointestinal tract were examined by fresh-frozen section immunohistologic techniques. In one case, a dense infiltrate in the small intestine, consisting of small lymphocytes with round nuclei, was limited almost entirely to the mucosa. In another case, a localized colonic polyp was formed by mucosal and submucosal lobules of benign-appearing lymphoid aggregates with centrally located germinal centers. The third case, a penetrating gastric ulcer, was surrounded by histologically hyperplastic lymphoid tissue which included germinal centers. The small lymphocytes in all three cases were strongly positive for B-cell-associated antigens (B1, B2, BA-1), and all exhibited monoclonal light-chain restriction. Even though treatment consisted only of surgical resection of the lesions, no patient has had progressive disease during follow-up periods ranging from 24 to more than 50 months. We believe that the infiltrates in these cases are analogous to the morphologically benign monoclonal small lymphocytic proliferations common to the lung and orbit and that they have an uncertain, but probably low, malignant potential.