Transient Metallo-Lipidoid Assemblies Amplify Covalent Catalysis of Aqueous and Non-Aqueous Reactions

Dissipative supramolecular assemblies are hallmarks of living systems, contributing to their complex, dynamic structures and emerging functions. Living cells can spatiotemporally control diverse biochemical reactions in membrane compartments and condensates, regulating metabolite levels, signal transduction or remodeling of the cytoskeleton. Herein, we constructed membranous compartments using self-assembly of lipid-like amphiphiles (lipidoid) in aqueous medium. The new double-tailed lipidoid features Cu(II) coordinated with a tetravalent chelator that dictates the binding of two amphiphilic ligands in cis-orientation. Hydrophobic interactions between the lipidoids coupled with intermolecular hydrogen bonding led to a well-defined bilayer vesicle structure. Oil-soluble SNAr reaction is efficiently upregulated in the hydrophobic cavity, acting as a catalytic crucible. The modular system allows easy incorporation of exposed primary amine groups, which augments the catalysis of retro aldol and C-N bond formation reactions. Moreover, a higher-affinity chelator enables consumption of the Cu(II) template leveraging the differential thermodynamic stability, which allows a controllable lifetime of the vesicular assemblies. Concomitant temporal upregulation of the catalytic reactions could be tuned by the metal ion concentration. This work offers new possibilities for metal ion-mediated dynamic supramolecular systems, opening up a massive repertoire of functionally active dynamic "life-like" materials.

Light-gated specific oxidase-like activity of a self-assembled Pt(II) nanozyme for environmental remediation

Artificial enzyme equivalents, also known as nanozymes, are a practical tool for environmental remediation when compared to their natural counterparts due to their high operational stability, efficiency, and cost-effectiveness. Specific oxidase mimicking nanozymes are well suited to degrade toxic chemicals from industrial waste such as phenols and azo dyes. Therefore, photocatalytic nanozymes using visible/sunlight would provide a viable strategy for sustainable environmental remediation. Herein, we introduce an aggregation-induced emissive Pt(II) complex, which self-assembles in water providing NanoPtA nanotapes. These structures exhibit a specific oxidase-like nanozyme activity driven by light. The NanoPtA structure assists in the photogeneration of singlet oxygen in water via a triplet excited 3MMLCT state, leading to a specific oxidase-like activity instead of a peroxidase-like activity. The self-assembled nanozyme showed great stability under harsh environmental conditions and exhibited photo-induced specific oxidase-mimetic activity, which was considerably more efficient than the natural enzyme or other specific nanozymes. We demonstrated efficient NanoPtA-induced photocatalytic degradation of various phenolic compounds and azo dyes within 5-10 minutes of light irradiation. Notably, the system operates under sunlight and exhibits reusability over twenty cycles of catalytic reactions. Another fascinating aspect of NanoPtA is the unaltered catalytic performance for more than 75 days, providing a robust enzyme-equivalent for practical sustainable environmental remediation.

Consequences of adaptation to larval crowding on sexual and fecundity selection in Drosophila melanogaster

Sexual selection is a major force influencing the evolution of sexually reproducing species. Environmental factors such as larval density can manipulate adult condition and influence the direction and strength of sexual selection. While most studies on the influence of larval crowding on sexual selection are either correlational or single-generation manipulations, it is unclear how evolution under chronic larval crowding affects sexual selection. To answer this, we measured the strength of sexual selection on male and female Drosophila melanogaster that had evolved under chronic larval crowding for over 250 generations in the laboratory, along with their controls which had never experienced crowding, in a common garden high-density environment. We measured selection coefficients on male mating success and sex-specific reproductive success, as separate estimates allowed dissection of sex-specific effects. We show that experimental evolution under chronic larval crowding decreases the strength of sexual and fecundity selection in males but not in females, relative to populations experiencing crowding for the first time. The effect of larval crowding in reducing reproductive success is almost twice in females than in males. Our study highlights the importance of studying how evolution in a novel, stressful environment can shape adult fitness in organisms.

Investment in adult reproductive tissues is affected by larval growth conditions but not by evolution under poor larval growth conditions in Drosophila melanogaster

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Growing at different larval densities affect the investment in reproductive tissues

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Increased larval density negatively affects the testis and accessory gland size

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Relative investment in testis is not affected by larval densities

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Increased larval densities affect relative accessory gland size negatively

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Adaptation to high larval crowding does not affect investment in reproductive tissues

In many insects, the larval environment is confined to the egg-laying site, which often leads to crowded larval conditions, exposing the developing larvae to poor resource availability and toxic metabolic wastes. Larval crowding imposes two opposing selection pressures. On one hand, due to poor nutritional resources during developmental stages, adults from the crowded larval environment have reduced investment in reproductive tissues. On the other hand, a crowded larval environment acts as a cue for future reproductive competition inducing increased investment in reproductive tissues. Both these selection pressures are likely affected by the level of crowding. The evolutionary consequence of adaptation to larval crowding environment on adult reproductive investment is bound to be a result of the interaction of these two opposing forces. In this study, we used experimentally evolved populations of Drosophila melanogaster adapted to larval crowding to investigate the effect of adaptation to larval crowding on investment in reproductive organs (testes and accessory glands) of males. Our results show that there is a strong effect of larval developmental environment on absolute sizes of testes and accessory glands. However, there was no effect of the developmental environment when testis size was scaled by body size. We also found that flies from crowded cultures had smaller accessory gland sizes relative to body size. Moreover, the sizes of the reproductive organs were not affected by the selection histories of the populations. This study highlights that adaptation to two extremely different developmental environments does not affect the patterns of reproductive investment. We discuss the possibility that differential investment in reproductive tissues could be influenced by the mating dynamics and/or investment in larval survival traits, rather than just the developmental environment of the populations.

Incidence of Granulomatous Mastitis at Saveetha Medical College and Hospital for the Past Two Years

Background: To find the incidence of Granulomatous mastitis at Saveetha Medical College and Hospital for a period of past two years. Methods: Retrospective study Incidence of Granulomatous Mastitis at Saveetha Medical College and Hospital for the past two years. The specimens were received from the histopathology section of the pathology department. Detailed gross examination of the specimen was done. This was followed by fixation and staining, done using hematoxylin and eosin stains. Results: In the period of two years from 2019 to 2020, 10 cases have been reported . Out of which five cases belonged to the reproductive age group, two cases in the post menopausal age group and three cases belonged to peri menopausal age group. All the patients presented with a lump on the breast and abscess. The treatment consists of corticosteroid therapy and minimal surgical intervention. Conclusion: Granulomatous mastitis is an inflammatory condition that mimics carcinoma of breast. Hence diagnosis is mainly made through exclusion and examination of histopathology slides. Core needle biopsy is the gold standard technique used in the diagnosis of the condition. It’s a self limiting disease, and requires surveillance,corticosteroid therapy and surgical intervention.

Evolution of sex-specific heat stress tolerance and larval Hsp70 expression in populations of Drosophila melanogaster adapted to larval crowding

The ability to tolerate temperature stress is an important component of adult fitness. In holometabolous insects like Drosophila melanogaster, adult stress resistance can be affected by growth conditions experienced during the larval stages. Although evolution under crowded larval conditions is known to lead to the correlated evolution of many adult traits, its consequences on adult heat stress tolerance have not been investigated. Therefore, in the present study, we assessed the adult heat stress tolerance in populations of D. melanogaster adapted to a stressful larval crowding environment. We used replicate populations of D. melanogaster, selected for adaptation to larval crowding stress (MCUs), for more than 230 generations, and their respective controls (MBs). Larvae from selected and control populations were grown under crowded and uncrowded conditions, and their adult heat shock resistance at two different temperatures was measured. Further, we compared Hsp70 expression in crowded and uncrowded larvae of both populations and also measured the Hsp70 expression after a mild heat treatment in adults of selected and control populations. Our results showed that adaptation to larval crowding leads to the evolution of Hsp70 gene expression in larval stages and improves adult heat stress tolerance ability in males, but not in females.

Lactobacillus fermentum (MTCC-5898) alleviates Escherichia coli-induced inflammatory responses in intestinal epithelial cells by modulating immune genes and NF-κB signalling

AIM

Dietary intervention using probiotic bacteria has emerged as a promising preventive strategy in addressing foodborne infections or gastrointestinal disorders. This study investigated the immunomodulatory effects of Lactobacillus fermentum (MTCC-5898) on Escherichia coli-induced inflammatory responses in intestinal epithelial cells.

METHODS AND RESULTS

The immune response of intestinal cells (Caco-2) in the presence of probiotic Lact. fermentum was determined during exclusion, competition and displacement of E. coli as the inflammatory agent. To achieve this objective, transcriptional modulation of key immune-related genes (cytokines, pattern recognition receptors and NF-κB), release of cytokines and nuclear translocation of the NF-κB subunit p-65 were studied. Expression of pro-inflammatory cytokines IL-8, TNF-α, IFN-ϒ and IL-23 was high in E. coli-exposed intestinal cells. However, overexpression of these E. coli-induced pro-inflammatory cytokines was prevented by Lact. fermentum during exclusion and competition assays. It also modulated the transcriptional expression of regulatory cytokines (IL-10 and TGF-β), pattern recognition receptors (TLR-2 and TLR-4) and genes associated with master inflammatory regulators (NF-κB and SIGIRR) to reduce E. coli-induced inflammation. The protective effect of Lact. fermentum was further confirmed by suppression of nuclear translocation of cytoplasmic NF-κB subunit (p-65).

CONCLUSION

Lactobacillus fermentum alleviated E. coli-induced inflammatory responses by modulating the NF-κB signalling besides pro-inflammatory and regulatory cytokines expression.

SIGNIFICANCE AND IMPACT OF THE STUDY

Lactobacillus fermentum holds significant promise as a potent nutraceutical that prevents and manages inflammatory gut-associated dysfunctions.

Evolution of pathogen-specific improved survivorship post-infection in populations of Drosophila melanogaster adapted to larval crowding

The environment experienced by individuals during their juvenile stages has an impact on their adult stages. In holometabolous insects like Drosophila melanogaster, most of the resource acquisition for adult stages happens during the larval stages. Larval-crowding is a stressful environment, which exposes the larvae to scarcity of food and accumulation of toxic waste. Since adult traits are contingent upon larval stages, in larval-crowding like conditions, adult traits are prone to get affected. While the effect of resource limited, poor-developmental environment on adult immune response has been widely studied, the effect of adaptation to resource-limited developmental environment has not been studied, therefore in this study we assayed the evolution of ability to survive infection in adult stages as a correlated response to adaptation to larval crowding environments. Using four populations of Drosophila melanogaster adapted to larval crowding for 240 generations and their respective control populations, we show that populations adapted to larval crowding show an improved and evolved post-infection survivorship against a gram-negative bacteria Pseudomonas entomophila. Whereas, against a gram-positive bacteria Enterococcus faecalis, no difference in post-infection survivorship was observed across control and selected populations. In this study, we report the co-related evolution of pathogen-specific increased survivorship post-infection in populations of Drosophila melanogaster as a result of adaptation to larval crowding environment.

Protective effects of casein-derived peptide VLPVPQK against hydrogen peroxide–induced dysfunction and cellular oxidative damage in rat osteoblastic cells

Oxidative stress inhibits osteoblast differentiation and function that lead to the development of osteoporosis. Casein-derived peptide VLPVPQK (PEP), a potent antioxidant, was isolated from β-casein of buffalo milk. We used an in vitro oxidative stress model induced by hydrogen peroxide (H2O2) in rat osteoblastic cells to investigate the protective effects of PEP against H2O2-induced dysfunction and oxidative damage. Cells were pretreated with PEP (50–200 ng/mL) for 2, 7 or 21 days followed by 0.3 mM H2O2 treatment for 24 h and then markers of osteogenic development, oxidative damage and apoptosis were examined. PEP significantly increased the viability and differentiation markers of osteoblast cells such as alkaline phosphatase and calcium mineralization. Moreover, PEP suppressed the production of reactive oxygen species (ROS), lipid peroxidation and ameliorated H2O2-induced reduction in glutathione, superoxide dismutase and catalase activities. In addition, PEP partially inhibited caspase-9 and-3 activities and reduced propidium iodide–positive cells. Altogether, our results demonstrated that PEP could protect rat osteoblast against H2O2-induced dysfunction and oxidative damage by reduction of ROS production, lipid peroxidation and increased antioxidant enzyme activities. Thus, our data suggest that PEP might be a valuable protective agent against oxidative stress–related diseases such as osteoporosis.

Cross-talk between probiotic lactobacilli and host immune system

The mechanism by which probiotic lactobacilli affect the immune system is strain specific. As the immune system is a multicompartmental system, each strain has its way to interact with it and induce a visible and quantifiable effect. This review summarizes the interplay existing between the host immune system and probiotic lactobacilli, that is, with emphasis on lactobacilli as a prototype probiotic genus. Several aspects including the bacterial-host cross-talk with the mucosal and systemic immune system are presented, as well as short sections on the competing effect towards pathogenic bacteria and their uses as delivery vehicle for antigens.

Evaluation of juxta-apical radiolucency in cone beam CT images

OBJECTIVES

The aim of this study was to analyse the position and relationship of juxta-apical radiolucency (JAR) to the mandibular canal and buccal and/or lingual cortical plates using cone beam CT (CBCT).

METHODS

A retrospective study was carried out to analyse the JAR on CBCT for 27 patients. These findings were compared with 27 age- and sex-matched patients without the presence of JAR, which acted as the control group. The CBCT images were analysed according to a checklist, to evaluate the position of the JAR and its relationship to the mandibular canal. Then, any thinning or perforation of either the buccal or lingual cortical plate due to JAR was noted, and a classification to quantify the thinning of cortical plates was proposed. The findings in the two groups were analysed using a paired comparison by McNemar test.

RESULTS

A statistical increased thinning of cortical plates was seen in the JAR group compared with the control group, and most of the cases were in the J3 group. None of the patients in either the JAR or the control group showed perforation of the buccal and/or lingual cortical plate on CBCT images.

CONCLUSIONS

A classification to quantify the thinning of cortical plates was proposed, which may be used for objective evaluation of the thinning of the cortical plates in future studies. The present study gives an insight into the relationship of the juxta-apical area with the mandibular canal and cortical plates in the mandible using CBCT.

Induction of immune tolerance to caseins and whey proteins by oral intubation in mouse allergy model

This study was designed to evaluate the effect of oral tolerance of caseins (CSN) and whey proteins (WP) in alleviating the allergic response to cow's milk proteins in Swiss albino mice raised on a milk protein-free diet. Oral tolerance was induced by feeding mice with 20 mg of CSN or WP once in a day for 4 days consecutively before immunization with respective protein by intraperitoneal (i.p.) injections (20 μg 200 per μl of PBS) using 2% of alum Al(OH)3 as adjuvant. Three weeks later, oral tolerance induction was analysed in humoral and cellular compartments of CSN- and WP-fed versus saline-fed control mice groups by measuring seric and intestinal antibody responses, mRNA abundance in splenic tissue and cytokine secretion patterns. The specific serum immunoglobulin-E (IgE) levels were significantly suppressed (p < 0.05), while sIgA was enhanced in these groups when compared with their respective saline-fed mice. Moreover, the mRNA levels of interferon-γ (IFN-γ) and interleukin-4 (IL-4) in both CSN- and WP-tolerized mice were found to be significantly decreased, while the abundance of interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) was increased significantly, as compared to respective control groups. Finally, cytokine profiles indicated a reciprocal decrease in IL-4 and IFN-γ versus an increase in IL-10 secretions in supernatants of cultured splenocytes of tolerized mice. Taken together, these results clearly showed that oral administration of cows' milk caseins and whey proteins can induce significant hyposensitization in mice, with the participation of suppressor cytokines.

Effect of supplementation of vitamin E, copper and zinc on the in vitro phagocytic activity and lymphocyte proliferation index of peripartum Sahiwal (Bos indicus) cows

To study the effect of vitamin E (VE), copper (Cu) and zinc (Zn) supplementation on the in vitro phagocytic activity (PA) and lymphocyte proliferation response (LPR) of blood neutrophils and lymphocytes, thirty Sahiwal pregnant cows (six in each group) in their late gestation at 30 days before the expected date of calving were selected from the NDRI experimental herd and supplemented with various micronutrients from 30 days before calving to 45 days after calving. Cows were supplemented individually with VE (1000 IU/cow/day), Cu (20 ppm/cow/day) and Zn (80 ppm/cow/day) and also with a combination of VE, Cu and Zn to study cumulative effect of all micronutrients. One group without any supplementation acted as a control. Blood neutrophils and lymphocytes were isolated and studied for their PA and LPR. Supplementation of micronutrients like VE, Cu, Zn and a combination of all these nutrients significantly (p < 0.01) increased the PA of experimental cows as compared to control (unsupplemented) cows during the pre-partum period. During post-partum, all the micronutrients (VE, Cu, Zn and their combination) showed a significant (p < 0.01) increase in the PA of experimental cows as compared to control cows. Of all the groups, significant (p < 0.01) and maximum PA was observed in the combination group followed by Zn-supplemented group during both the pre- and post-partum period. A significant (p < 0.01) increase in LPR of B lymphocytes was observed in combination-supplemented group during the pre-partum period and during both the pre- and post-partum period in the Cu-supplemented group.

In vitro phagocytic activity of milk neutrophils during lactation cycle in Murrah buffaloes of different parity

Milk samples were collected from 34 lactating Murrah buffaloes on days 0, 5, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270 and day 300 after calving. Milk somatic cell counts (SCC) were highest in multiparous buffaloes. Milk SCC were significantly lower in buffaloes of third and fourth parity during early lactation and than increased significantly (p < 0.01) by the end of lactation. Milk neutrophils were significantly lower in all the buffaloes during early lactation, but increased significantly (p < 0.01) afterwards. Milk lymphocytes were significantly higher during early lactation, but decreased significantly (p < 0.01) by the end of lactation. Phagocytic activity (PA) was highest in day 1 colostrum and then decreased significantly (p < 0.01) by the fourth milking in buffaloes of second, third and fourth parity. Phagocytic index (PI) was also highest in colostrums of primiparous buffaloes. Irrespective of parity, maximum PA and PI was observed during mid lactation. In terms of in vitro phagocytic activity, early lactation is the most critical period followed by late and mid lactation.

Skin conductance as a means to predict hypotension following spinal anaesthesia

BACKGROUND AND OBJECTIVE

Hypotension following spinal anaesthesia (SA) is common, especially in the elderly. Elevated sympathetic tone has been shown to correlate with severe hypotension after SA. The aim of this prospective trial was to investigate skin conductance (SC), as a measure of sympathetic tone, to predict hypotension after SA.

METHODS

After ethical approval and written informed consent, 30 patients undergoing SA were included. Baseline measurements of SC [number of fluctuations per second (reflecting the firing rate of skin sympathetic nerves), area under the curve (AUC) A and B (reflecting the magnitude of the sympathetic impulse)], blood pressure and heart rate were recorded. After administration of SA, all parameters were assessed every 2.5 min for a total of 15 min. Baseline readings of SC were compared with the lowest blood pressure within the study period.

RESULTS

Data from 30 subjects [73 (8) years] were analysed. After SA, the mean arterial blood pressure declined an average of 21.3 (11.3) mmHg. A cut-off value of 0.35 microSs for baseline AUC B allowed prediction of more than mild hypotension (>15% from baseline) after SA with a sensitivity of 72.5% and a specificity of 77.5%.

CONCLUSIONS

AUC B, as a parameter of SC, may predict severe arterial hypotension after SA in the elderly.

New parameters of skin conductance compared with bispectral index ® monitoring to assess emergence from total intravenous anaesthesia

BACKGROUND

Arousal after total i.v. anaesthesia (TIVA) has been reported to be detectable by monitoring the number of fluctuations per second (NFSC), a parameter of skin conductance (SC). However, compared with monitoring of the bispectral index (BIS), the predictive probability of NFSC was significantly lower. The aim of this study was to determine the value of the two new, not yet published parameters of SC, area under the curve (AUC) methods A and B, for monitoring emergence from TIVA compared with monitoring of NFSC and BIS.

METHODS

Twenty-five patients undergoing surgery were investigated. NFSC, AUC A, AUC B, BIS, and haemodynamic parameters (mean arterial pressure and heart rate) were recorded simultaneously. The performance of the monitoring devices in distinguishing between the clinical states 'steady-state anaesthesia', 'first clinical reaction', and 'extubation' were compared using the method of prediction probability (Pk) calculation.

RESULTS

BIS showed the best performance in distinguishing between 'steady-state anaesthesia' vs 'first reaction' (Pk BIS 0.95; NFSC 0.73; AUC A 0.54; AUC B 0.62) and 'steady-state anaesthesia' vs 'extubation' (Pk BIS 0.99; NFSC 0.73; AUC A 0.71; AUC B 0.67). However, the time from first BIS>60/SC>0 to a first clinical reaction was significantly shorter for BIS (median BIS((R)) 180 s; NFSC 780 s; AUC A 750 s; AUC B 690 s; P < 0.001).

CONCLUSIONS

AUC A and AUC B did not improve accuracy of SC monitoring in patients waking after TIVA.

Necrotizing fasciitis: a deadly infection

Necrotizing fasciitis (NF) is a life-threatening condition, consisting of a soft-tissue infection with rapidly progressive, widespread fascial necrosis. NF may be caused by a wide variety of microbes. Indeed, NF may be an infection of one species of bacteria or may be polymicrobial. Prompt diagnosis and treatment are essential. Surgical debridement and antibiotic therapy are the primary treatment options.

Rocky Mountain spotted fever

Rocky Mountain spotted fever (RMSF) is an unusual but important dermatological condition to identify without hesitation. The classic triad of headache, fever, and a rash that begins on the extremities and travels proximally to involve the trunk is found in a majority of patients. The cutaneous centripetal pattern is a result of cell to cell migration by the causative organism Rickettsia rickettsii. Such individuals should receive prompt antimicrobial therapy and supportive care to avoid serious and potentially fatal complications.

Pyoderma vegetans

BACKGROUND

Pyoderma vegetans is a rare condition that is clinically characterized by large verrucous plaques with elevated borders and multiple pustules. The etiology of this disorder remains unknown.

OBJECTIVES

We describe a 24-year-old woman with rapidly evolving pyoderma vegetans. Our patient had the unique additional findings of a highly elevated serum IgE level and a history of hidradenitis suppurativa.

CONCLUSIONS

Pyoderma vegetans is diagnosed on clinical and histological criteria. Differentiation must be made from disorders such as pyoderma gangrenosum, Sweet's syndrome, and deep fungal infections. We illustrate a case of pyoderma vegetans and review the literature on this rare disorder. Clinical and histological criteria for diagnosis are presented, as well as differentiation from some mimicking disorders.

Tuberculous gumma (cutaneous metastatic tuberculous abscess) with underlying lymphoma

Cutaneous tuberculosis is an infrequent first sign of disseminated tuberculosis. We describe a patient with 2 cutaneous ulcerations that grew Mycobacterium tuberculosis. Despite an initial response to antimycobacterial therapy, the fever relapsed. After several months, biopsy of a single cervical lymph node showed a T cell-rich B cell lymphoma. Our patient had metastatic tuberculous abscesses (tuberculous gummas), which are secondary to disseminated tuberculosis, and an underlying occult lymphoma, both believed to be sequentially presenting as a fever of unknown origin.

Bacillary angiomatosis in an HIV seronegative patient on systemic steroid therapy

Bacillary angiomatosis is an unusual systemic vascular proliferation seen predominantly in patients with the acquired immunodeficiency syndrome. These vascular lesions are due to infection with a Bartonella species, most commonly B. henselae, but sometimes B. quintana. It is treatable and often curable, but without therapy may be life-threatening. Clinically, the disorder often resembles several different vascular disorders, particularly pyogenic granuloma and Kaposi's sarcoma. We now report a clinically typical patient with bacillary angiomatosis who was HIV seronegative, but who had idiopathic thrombocytopenic purpura, was status-post splenectomy and to whom long-term systemic prednisone had been administered.

Overwhelming postsplenectomy infection

The incidence of overwhelming sepsis in asplenic patients is low. It carries, however, an unacceptably high morbidity rate and mortality rate. The risk of development is related to the age of the patient as well as the duration since and the reason for splenectomy. It may also occur in functionally hyposplenic states. The rapidly lethal clinical course demands intense efforts toward prevention by both physician and patient, rapid recognition within the initial medical setting, and aggressive intervention with broad-spectrum antibiotics and other supportive measures.

A new family of dispersed repeats from Brassica nigra: characterization and localization

The 459-bp HindIII (pBN-4) and the 1732-bp Eco RI (pBNE8) fragments from the Brassica nigra genome were cloned and shown to be members of a dispersed repeat family. Of the three major diploid Brassica species, the repeat pBN-4 was found to be highly specific for the B. nigra genome. The family also hybridized to Sinapis arvensis showing that B. nigra had a closer relationship with the S. arvensis genome than with B. oleracea or B. campestris. The clone pBNE8 showed homology to a number of tRNA species indicating that this family of repeats may have originated from a tRNA sequence. The species-specific 459-bp repeat pBN-4 was localized on the B. nigra chromosomes using monosomic addition lines. In addition to the localization of pBN-4, the chromosomal distribution of two other species-specific repeats, pBN34 and pBNBH35 (reported earlier), was studied. The dispersed repeats pBN-4 and pBNBH35 were found to be present on all of the chromosomes, whereas the tandem repeat pBN34 was localized on two chromosomes.

A novel species-specific tandem repeat DNA family from Sinapis arvensis: detection of telomere-like sequences

DNA sequences representing a tandemly repeated DNA family of the Sinapis arvensis genome were cloned and characterized. The 700-bp tandem repeat family is represented by two clones, pSA35 and pSA52, which are 697 and 709 bp in length, respectively. Dot matrix analysis of the sequences indicates the presence of repeated elements within each monomeric unit. Sequence analysis of the repetitive region of clones pSA35 and pSA52 shows that there are several copies of a 7-bp repeat element organized in tandem. The consensus sequence of this repeat element is 5'-TTTAGGG-3'. These elements are highly mutated and the difference in length between the two clones is due to different copy numbers of these elements. The repetitive region of clone pSA35 has 26 copies of the element TTTAGGG, whereas clone pSA52 has 28 copies. The repetitive region in both clones is flanked on either side by inverted repeats that may be footprints of a transposition event. Sequence comparison indicates that the element TTTAGGG is identical to telomeric repeats present in Arabidopsis, maize, tomato, and other plants. However, Bal31 digestion kinetics indicates non-telomeric localization of the 700-bp tandem repeats. The clones represent a novel repeat family as (i) they contain telomere-like motifs as subrepeats within each unit; and (ii) they do not hybridize to related crucifers and are species-specific in nature.

Invasive rhinosino-orbital aspergillosis with precipitous visual loss

OBJECTIVE

To describe the clinicopathological and radiologic features in five cases of primary and secondary orbital aspergillosis.

DESIGN

Case series.

SETTING

Ophthalmology department of a university hospital.

PATIENTS

Five patients over 65 years of age with invasive rhinosino-orbital aspergillosis.

RESULTS

Presenting features were abrupt onset of proptosis, ophthalmoplegia and blepharoptosis with precipitous visual loss. All had debilitating periorbital pain or headache, but none had orbital inflammatory signs or appeared "toxic." Predisposing causes included alcoholism, low-dose prednisone therapy and insulin-dependent diabetes mellitus. One patient, suspected of having mucormycosis based on tissue biopsy and results of potassium hydroxide preparations, harboured Aspergillus fumigatus, which grew on culture. Secondary bacterial infections developed in three patients. Three patients died from their disease despite aggressive surgical treatment, including exenteration and sinus extirpation. The one patient with primary orbital aspergillosis survived after exenteration.

CONCLUSIONS

Sinonasal aspergillosis with orbital extension and primary orbital aspergillosis have a precipitous clinical course that mimics that of mucormycosis and may be fatal despite early exenteration. Computed tomography and magnetic resonance imaging of the sinuses, orbit and head provide complementary diagnostic signs. While results of potassium hydroxide preparations and tissue biopsy guide treatment of fungal infection, definitive diagnosis requires fungal culture. Relatively good vision may be associated with massive orbital and secondary intracranial extension.

Infection after insertion of alloplastic orbital floor implants

Ten patients developed infections after alloplastic implantation (nine silicone, one gelatin film [Gelfilm] implant) for orbital floor fracture repair. Infection resulted from the following: (1) dental surgery, (2) upper respiratory infection, (3) inferior extrusion of a retained implant into the maxillary sinus with a fistulous tract into the inferior conjunctival fornix, (4) rhinoplasty, (5) snorting cocaine and other drugs, (6) postoperative infection after orbital floor repair, and (7) medial implant migration resulting in chronic dacryocystitis. In all ten patients, implants were removed because of orbital abscess, recurrent infection, or chronic low-grade infections. Microbiologic culture of removed implants disclosed Staphylococcus aureus, S. epidermidis, Serratia marcescens, and Pseudomonas aeruginosa as the offending organisms. The main complication of infection included severe cicatricial ectropion of the lower eyelid in three patients. The final globe position was not adversely affected by implant removal performed from five months to 20 years after insertion. Guidelines for prevention and management of orbital implant infections based on these ten patients are presented.

Acrosome damage and enzyme leakage of goat spermatozoa during dilution, cooling and freezing

Semen of Jamunapari goat bucks was frozen in three diluents egg yolk-tris, egg yolk/citrate/glucose, and skim milk/egg yolk. In fresh ejaculated semen over 90% of the spermatozoa had normal head and acrosome morphology. Quantification of goat sperm structure with Giemsa stain revealed significant (P < 0.01) damage to acrosome on freezing which varied between 38 to 43% in three diluents. Scanning electron microscopy defined and revealed greater damage during freezing with 50% sperm heads having normal acrosome structure in three diluents. The ultrastructural changes detected in frozen goat sperm was protrusion at the anterior cap, broken tail, swelling of acrosome, and loss of acrosomal contents. The leakage of five enzymes GOT, GPT, hyaluronoglucosaminidase, acid phosphatase, and alkaline phosphatase measured simultaneously revealed a positive correlation between enzyme release and acrosomal damage.

The febrile parenteral drug user: a prospective study in 121 patients

OBJECTIVE

To determine the most efficient approach to the diagnosis of infective endocarditis (IE) in febrile parenteral drug users (PDUs) and evaluate possible effects of human immunodeficiency virus (HIV) infections or acquired immunodeficiency syndrome (AIDS) on susceptibility to IE and final outcome.

DESIGN

A prospective study of appropriate patients admitted on 149 random sampling days during a 14-month period and review of past experience with IE, HIV, and AIDS admissions to hospital.

SETTING

An urban university hospital.

PATIENTS

Prospectively, 121 febrile PDUs plus an additional 16 found to have IE on nonsampling days during the study period. Retrospectively, all PDUs with IE from 1985 to 1991 and all patients with HIV infections with or without AIDS from July 1990 through December 1991.

MEASUREMENTS

Physical examination, hemograms, urinalysis, blood cultures (plus other body fluids when indicated), echocardiography, laboratory testing for HIV status.

MAIN RESULTS

Five categories of patients were identified: I. Infective endocarditis (n = 16); II. Other infections with bacteremia (n = 21); III. Bacteremia with unidentified source of infection (n = 14); IV. Infections without bacteremia (n = 52); V. Fever of unknown origin (n = 18). Physical findings and standard laboratory testing did not differentiate Group I from any of the other diagnostic categories. Adding additional IE cases from nonstudy days brought the total to 32. Vegetations were found on echocardiography in 94%; blood cultures, available in 30 of 32 instances, were all positive. HIV or AIDS status was not found to alter susceptibility to IE or influence mortality. While hospital admissions for HIV and especially AIDS have continued to increase among PDUs, the number of cases of IE has decreased since 1988 to 1989.

CONCLUSIONS

Based on the high incidence of blood culture positivity and the sensitivity of echocardiography in detecting vegetations in IE, a simple algorithm has been developed for the initial diagnostic management of febrile PDUs admitted with the possible diagnosis of IE. HIV infection, with or without full-blown AIDS, does not appear to affect the incidence or outcome of IE among these patients. Current practices among PDUs may be effecting a decline in IE but not HIV infections.

Meningitis due to Prototheca wickerhamii in a patient with AIDS

The first documented case of algal meningitis due to Prototheca wickerhamii is reported in a patient with AIDS. The initial CSF culture yielded only Cryptococcus neoformans. P. wickerhamii was isolated on four subsequent lumbar punctures. The patient died, and at autopsy the alga was isolated from leptomeninges over the brain and about the spinal cord. Histologic sections from numerous locations of the brain revealed masses of cryptococci and prototheca.

Independent mosaics of large inner- and outer-stratified ganglion cells in the goldfish retina

Goldfish retinal ganglion cells were filled with horseradish peroxidase and studied in flatmounts. Two regular mosaics of large neurons with many of the properties of mammalian alpha ganglion cells were found, differing from each other in spacing, size, and dendritic stratification. The existence of biplexiform ganglion cells with additional dendrites in the outer plexiform layer was also confirmed. One of the two alpha-like mosaics consisted of giant ganglion cells with thick primary dendrites and large, sparsely branched dendritic trees in the outer sublamina of the inner plexiform layer (IPL). In fish 55-65 mm long, about 300 formed a tessellated array across each retina. Their somata (mean area 277 +/- 6 microns 2) were displaced to varying degrees into the IPL, neighbours in the mosaic often occupying different levels. Their dendrites ramified in one stratum near the inner nuclear layer, at a mean depth of 70.8 +/- 0.5% of the IPL. The other alpha-like mosaic comprised about 900 large ganglion cells, with slightly smaller somata (mean area 193 +/- 4 microns 2) in the ganglion cell layer. Most of their dendrites lay in a narrow stratum at 41.9 +/- 0.5% of the depth of the IPL. However, deviations (usually into more vitread strata) were common, which was not true for similar cells in the distantly related cichlid fish Oreochromis. Measurements of nearest neighbour distance (NND) for 4 outer and 4 inner mosaics showed that they were at least as regular as the alpha cell mosaics of mammals: the ratio of the mean NND to the standard deviation ranged from 4.03 for the least regular outer mosaic to 6.47 for the most regular inner mosaic. The wide phylogenetic distribution of these paired, regular mosaics points to a fundamental role in vision. The presence of some variability in dendritic stratification even within the exceptionally regular inner-stratified mosaic suggests that classifications based entirely on the detailed morphology of individual neurons may not always correlate well with their primary functional roles. Where possible, neuronal morphology and spatial distribution should be studied together.

Anonymous human immunodeficiency virus surveillance and clinically directed testing in a Newark, NJ, hospital

From September 1988 to August 1989, in a university hospital in Newark, NJ, 3529 serum and plasma specimens from patients with admitting conditions presumably not associated with human immunodeficiency virus (HIV) infection (Centers for Disease Control, Atlanta, Ga, Sentinel Hospital Surveillance System criteria) were tested anonymously for the presence of type 1 HIV (HIV-1) antibody. Of these specimens, 269 (7.6%) were confirmed HIV-1 seropositive. Overall, 10.3% of male patients and 4.8% of female patients were seropositive. Persons 25 to 44 years old had the highest HIV-1 seroprevalence- 20.9% for male and 7.5% for female patients. Based on this anonymous testing, the number of HIV-infected hospitalized patients discharged in 1988 was estimated. Data on hospital-confirmed HIV-infected patients tested on the basis of clinical suspicion suggest that only 40% of HIV-infected patients were actually tested for HIV-1 infection as part of their medical care in this hospital. These data demonstrate a high prevalence of HIV infection in this patient population and suggest that hospitals serving populations with a high HIV seroprevalence offer routine screening for HIV infection as part of good medical care.

Sweet's syndrome with acute leukemia

Sweet's syndrome presenting with malignancy or acute neutrophilic dermatosis is an unusual cutaneous disorder associated most commonly with acute myelogenous leukemia. Although other cancers may be linked to acute neutrophilic dermatosis, a large majority of patients have associated neoplasms of hematopoietic, plasma cell, or lymphoid nature. We report a patient with aplastic anemia who showed acute neutrophilic dermatosis and, ultimately, acute leukemia. The individual lesions responded to carbon dioxide laser surgery.

Histoid lepromas of lepromatous leprosy

Histoid lepromas are a rare eruption in patients with lepromatous leprosy. A 59-year-old man from India with lepromatous leprosy who developed histoid lepromas and who was dapsone resistant was studied. These tumors resembled cutaneous metastases. This Indian man is to our knowledge the first patient to be reported with this rare disorder in the continental United States.

Cutaneous onchocerciasis

Onchocerciasis was diagnosed when a skin biopsy specimen immersed in saline revealed microfiliariae. The patient was a 22-year-old student from Cameroon, West Africa, complaining of small, recurrent, pruritic papules on his thighs. Chemotherapy with ivermectin, an established antiparasitic agent with newly recognized anti-onchocercal potential, was well tolerated, and microfilariae were not detected in post-therapy skin biopsy specimens. The diagnosis of onchocerciasis should be entertained in individuals returning or emigrating from endemic areas.

Yield of bone marrow culture in the diagnosis of infectious diseases in patients with acquired immunodeficiency syndrome

The yield in cultures of bone marrow aspirations or biopsies was determined in 50 patients with acquired immunodeficiency syndrome. Most patients were febrile and had no identifiable source of infection. Concurrent stool, urine, and blood samples were also cultured. The bone marrow aspiration and biopsy procedures produced no complications and enabled a microbiological diagnosis to be made in 42% of the cases. Granuloma formation was not seen in any of the infected bone marrow specimens despite the fact that mycobacteria were seen in abundance in some. Bone marrow culture is a valuable low-morbidity invasive procedure in the evaluation of febrile patients with acquired immunodeficiency syndrome.

Central nervous system tuberculosis with the acquired immunodeficiency syndrome and its related complex

Central nervous system tuberculosis occurred in three patients with the acquired immunodeficiency syndrome (AIDS) and seven patients with AIDS-related complex who were evaluated for 48 months. Nine patients were intravenous drug abusers and one was Haitian. Five patients had cerebral-ring-enhancing lesions and three had hypodense areas. The clinical spectrum included meningitis in two patients, multiple cerebral abscesses in one, and tuberculomas in four. All Mycobacterium tuberculosis isolates were sensitive to standard antituberculous drugs. All patients received treatment with isoniazid, rifampin, and pyrazinamide; six patients also received streptomycin. Three patients with AIDS died of opportunistic infection preceded by central nervous system tuberculosis. Among the patients with the AIDS-related complex, three improved with treatment, three were lost to follow-up, and one died. Tuberculosis should be considered in the differential diagnosis of central nervous system mass lesions in intravenous drug abusers with AIDS or AIDS-related complex. Because patients with tuberculosis can be cured, biopsy of accessible brain mass lesions should be mandatory. Preventive therapy may be indicated in drug abusers without disease.

Tuberculosis as a manifestation of the acquired immunodeficiency syndrome (AIDS)

Tuberculosis has not been well documented as a complication of the acquired immunodeficiency syndrome (AIDS). We studied 48 cases of mycobacterial diseases among a group of 136 adult patients with AIDS over a 43-month period. Twenty-nine of them had severe and unusual manifestations of disease due to Mycobacterium tuberculosis, predominantly extrapulmonary and disseminated. Tuberculosis was more common among Haitians (4/8) and intravenous drug abusers (24/102) than among homosexuals who did not abuse drugs (0/22). Twelve of 21 patients with tuberculosis who were treated responded well, whereas three developed progressive disease indicative of treatment failure. Severe and unusual presentation of overwhelming tuberculosis in appropriate clinical circumstances may be considered an infection predictive of the presence of AIDS.

Cryptococcal infections in patients with acquired immune deficiency syndrome

Cryptococcus neoformans is a major pathogen in patients with acquired immune deficiency syndrome and was found to infect 13.3 percent of such patients seen at two medical centers. Serum cryptococcal antigen levels were as high as 1:2,000,000 and, despite therapy, often remained elevated. Antigen titers in the cerebrospinal fluid generally declined at an expected rate in the survivors. The significance of high antigen titers in the blood after a prolonged course of therapy with amphotericin B and 5-flucytosine is unknown.

Bacteremia and fungemia in patients with acquired immune deficiency syndrome

Patients with acquired immune deficiency syndrome (AIDS) are known to have identifiable host defense deficiencies, especially deficiencies in cell-mediated immunity. They are at increased risk for developing infections of the bloodstream caused by Cryptococcus neoformans and Salmonella species. However, bacteremias caused by other enteric gram-negative rods and Pseudomonas aeruginosa are found less frequently in patients with AIDS than in patients without AIDS (P less than 0.001 and P less than 0.01, respectively). The findings of specific organisms in blood is consistent with the known types of host defense deficiencies in these patients.

Anterior thigh pain or tenderness. A diagnostically useful manifestation of bacteremia

In four patients with putative infectious process, anterior, bilateral proximal thigh pain and tenderness unaccompanied by generalized myalgias developed. This unusual manifestation, observed in these and other patients, was associated with demonstrable bacteremia. Aside from tenderness, no local abnormalities were found and the pain and tenderness disappeared after appropriate therapy. Creatine kinase levels, measured in three of the four patients, were elevated in only one. This manifestation is useful clinically as it strongly suggests bacteremia; attention to this finding can be lifesaving.

Actinomycetales infection in the acquired immunodeficiency syndrome

Four parenteral drug abusers with the acquired immunodeficiency syndrome had nonmycobacterial actinomycetales infections. Three patients had nocardiosis and one developed a streptomyces lymphadenitis. There was pericardial involvement in two patients, and two patients died. Presumptive diagnoses were often incorrect, highlighting the risks of empiric therapy in these patients. Four of the nine patients with the acquired immunodeficiency syndrome and nocardia or streptomyces infections whose cases were reported to the Centers for Disease Control also had mycobacterial disease. A common susceptibility to these agents may exist in these immunosuppressed patients.

Superinfection: another look

Superinfection in the compromised host often poses a diagnostic and therapeutic dilemma for the physician who is concerned that a perplexing array of microorganisms might be involved. We believe that the differential diagnosis list can often be narrowed considerably by separating superinfection in the compromised host into five convenient categories: (1) infections due to the underlying disease itself; (2) infections due to the underlying disease plus therapy for that disease; (3) infections due solely to medicaments, operations, or procedures; (4) infections increased in severity but probably not in incidence; and (5) societally related infections. Use of this or a similar categorization should result in a more rational approach to differential diagnosis, should encourage a more focused diagnostic work-up, whould reduce the necessity for invasive procedures, should provide the microbiology laboratory information about specific organisms that should be sought sedulously, and should permit the selection of a more rational antimicrobial regimen prior to the availability of definitive microbiologic information.

Fatal Streptococcus MG-intermedius (Streptococcus milleri) meningitis in an adult

A case of purulent meningitis in an adult caused by Streptococcus MG-intermedius, also known as Streptococcus milleri, is described. The intriguing taxonomical history of this organism and its association with mycoplasma pneumoniae pulmonary infections is reviewed. The incidence of central nervous system infections due to this organism is also discussed.

Clinical evaluation of intravenous trimethoprim-sulfamethoxazole for serious infections

The efficacy and safety of intravenous trimethoprim-sulfamethoxazole (TMP-SMZ) were evaluated in 22 adults with serious infections caused by gram-negative bacteria. These infections included pneumonia, meningitis, pyelonephritis, deep-seated abscesses, and endocarditis. Of the 19 patients who could be evaluated, 12 (63%) were cured, and four (21%) showed definite improvement; three patients (16%) failed to respond to treatment. The only serious side effect occurred in a patient who had an acute reaction after his first dose. Mild adverse reactions were relatively common: three patients (13.6%) developed skin rashes, in one case with bronchospasm and eosinophilia. Mild transient decline of renal function was observed in five patients (22.7%) and decline of hepatic function in seven patients (31.8%); these abnormalities were not necessarily attributable to the drug. Although side effects were more common than previous reports indicate, intravenous TMP-SMZ was effective in the treatment of life-threatening infections unresponsive to other antibiotics.