Sternohyoid or sternocleidomastoid muscle flap for tracheoesophageal puncture closure in irradiated patients: A CARE case series

INTRODUCTION

A novel technique for tracheoesophageal puncture (TEP) closure is described in which the sternohyoid muscles are rotated and interposed between the tracheal and esophageal walls. The results of this technique are reported, following CARE guidelines, and compared with those obtained using the sternocleidomastoid flap. A literature review on the techniques previously described for TEP closure in irradiated patients is presented.

CASE SERIES

The novel technique was performed in six patients in whom the infrahyoid muscles were preserved during total laryngectomy. All received adjuvant radiotherapy. Successful closure was achieved in three cases; in one case a small leak was noted after initial closure and was successfully managed with simple sutures; and the other two failures occurred in patients with diabetes. The sternocleidomastoid flap was performed in five patients (only one with previous radiation) and success was achieved in two patients. In another patient a micro-fistular orifice appeared six months after the operation.

DISCUSSION

The sternohyoid muscles pose a low morbidity alternative to be considered in surgical TEP closure. Patient selection is a key factor to surgical success, and this technique should be reserved for small to moderate size fistulas and in the absence of multiple impaired wound healing conditions.

Understanding Zenker's Diverticulum Treatment: Transoral CO2 Laser Microsurgery

The authors present a case of a 36-year-old woman with a recurrent throat foreign body sensation and persistent dysphagia. On physical examination, a polypoid mass was visible at the postcricoid region, mobile with swallowing. A barium swallowing test confirmed the diagnosis of Zenker's diverticulum. The patient underwent transoral CO2 laser microsurgery for excision of the pharyngeal pouch. At the four-month evaluation, the patient was remarkably asymptomatic and without evidence of recurrence. This clinical case illustrates in detail the endoscopic view of the pre and postoperative aspects of the pharyngeal pouch, showing a step-by-step transoral CO2 laser microsurgery technique, with video.

Comparison of Clinical and Pathological Staging in Patients with Head and Neck Cancer After Neck Dissection

Introduction  Clinical and pathological staging plays an important role on the prognosis of head and neck cancer (HNC) patients. Objective  The present study aims to compare clinical and pathological T, N and overall staging in patients with HNC, to identify factors associated with these discrepancies, and to analyze and compare survival or disease-free survival in staging disagreements. Methods  Retrospective cohort including every patient submitted to neck dissection from January 2010 to December 2020 in the department of Otorhinolaryngology of a tertiary hospital center. Results  A total of 79 patients were analyzed; their mean age was 58.52 ± 13.15 years old and 88.9% were male. Assessing overall staging, discrepancies were noted in 53% (36.4% upstaging and 16.6% downstaging) and were significantly associated with clinical overall staging ( p  = 0.006). Regarding T staging, differences were noted in 45.5% (30.3% upstaging and 15.2% downstaging) and were significantly associated with imaging modality ( p  = 0.016), clinical T staging ( p  = 0.049), and histology ( p  = 0.017). Discrepancies in N staging were noted in 38% (25.3% upstaging and 12.7% downstaging) and were significantly associated with age ( p  = 0.013), clinical N staging ( p  < 0.001), and presence of extranodal invasion ( p  < 0.001). Both in Overall, T, and N staging, the aforementioned disagreements were not associated with either higher mortality or higher disease relapse. Conclusion  Overall, T, and N staging disagree in an important number of cases, and the overall stage can disagree in up to 53% of the cases. These disagreements do not seem to influence overall and disease-free survival.

Is Computed Tomography Necessary Before Septoplasty? Correlation With Physical Examination and Patient Complaints

INTRODUCTION

Septoplasty is one of the most common surgeries performed by otorhinolaryngologists. The gold standard for the evaluation of septal deviation is anterior rhinoscopy and nasal endoscopy. Frequently, computed tomography (CT) is also performed, although the correlation between septal deviation on CT and physical examination is unclear.

OBJECTIVES

To study the relationship between symptoms and physical and radiological evaluation in patients who underwent septoplasty.

METHODS

A prospective study of patients with nasal obstruction and septal deviation who underwent septoplasty. Anterior rhinoscopy and nasal endoscopy were performed by the surgeon, and the CT was evaluated by a radiologist. The degree of obstruction was evaluated in three distinct septal locations. The Nasal Obstruction Symptom Evaluation (NOSE) score was used before the surgery and two months after the surgery.

RESULTS

The study included 43 patients, of whom 60.5% were male, with an average age of 37.09 years (±12.56). The degree of septal deviation in the physical examination was significantly different from that observed in CT (p˂0.05). Cartilaginous or maxillary crest septal deviations >75% were more commonly recognized by physical examination, while osseous septum deviations of 25%-50% were more easily detected by CT. There was no difference between the degree of septal deviation and the preoperative NOSE. The median preoperative NOSE was 60, and the postoperative was 5, with significant improvement (p<0.05).

CONCLUSION

CT doesn't appear to be useful in the evaluation of septal deviation since it is different from the findings of a physical examination and isn't associated with the NOSE score. Clinical decisions should be based on a physical examination and patient complaints.

Actinomyces and Shewanella algae complicated paediatric mastoiditis: a case report of a multidisciplinary approach

Cerebral venous sinus thrombosis in children is a rare complication of acute mastoiditis that can potentially be fatal. Clinical expertise is essential for early diagnosis and management due to its subtle course. We present the first known case of paediatric acute mastoiditis with venous sinus thrombosis caused by Shewanella algae and Actinomyces europaeus . A 17-year-old male presented clinical signs of right acute otitis media and mastoiditis. Brain computed tomography showed mastoid opacification, cerebral sinus thrombosis and an extradural collection. Microbiology revealed the presence of S. algae and A. europaeus . A multidisciplinary approach combining medical and surgical treatment allowed the patient to make a full recovery.

Voice rehabilitation with voice prosthesis: Long term results, complications and risk factors

OBJECTIVES

Despite the advances in surgical and non-surgical organ preservation treatments, total laryngectomy (TL) remains the most effective treatment in advanced larynx cancer and as salvage procedure in chemoradiation failure. One of the most devastating sequel after TL is loss of voice. Voice prosthesis (VP) is currently the preferred choice for voice rehabilitation. The purpose of this study is to identify VP complications, its lifespan and factors that influence the longevity of the VP.

METHODS

We performed a retrospective study at a Tertiary University Hospital. Medical records of patients that underwent total laryngectomy, between January 1st of 2008 and 31st of December of 2017 were analyzed.

RESULTS

Of the 84 patients that underwent laryngectomy, 60 had VP. The average age at the time of surgery 60.2 years old and there was a male preponderance (57:3). The mean lifespan of the prosthesis was 7.53 months. Leakage through the prosthesis was the most common reason for replacement of the prosthesis, followed by leakage around the prosthesis. Follow up time and manual suture were associated with prosthesis replacement. There was no significant relationship between the staging, tumor location or adjuvant radiotherapy and number of prosthesis replacement or its lifespan.

CONCLUSIONS

Rehabilitation after TL is of major importance to improve quality of life after surgery. Tracheoesophageal puncture with voice prosthesis is a safe procedure for vocal rehabilitation and was performed in the majority of patients in our study. Follow-up time and type of suture were the main determinants of the lifespan of the prosthesis.

Clown Nose: A Rare Hypopharyngeal Cancer Metastasis

Cutaneous metastases from squamous cell carcinomas of the head and neck region are uncommon, and their location at the nasal tip is exceptionally rare. A patient, previously treated with surgery and chemoradiation for a hypopharyngeal squamous cell carcinoma, developed several red nodular skin lesions at the nasal tip. Biopsy revealed cutaneous metastasis from the primary tumor. This manifestation was previously described as a "clown nose," given their appearance and location. Skin lesions should raise suspicion of malignancy, despite their location at uncommon places, particularly in patients with previous diagnosed cancer. Clinicians must be aware that metastases from head and neck cancer can present as a "clown nose."

Bioecological aspects of triatomines and marsupials as wild Trypanosoma cruzi reservoirs in urban, peri-urban and rural areas in the Western Brazilian Amazon

In the Amazon region, Trypanosoma cruzi transmission cycles involve a great diversity of Triatominae vectors and mammal reservoirs. Some Rhodnius spp. mainly inhabit palm trees that act as microhabitats for hosts and vectors. The current study aimed to describe aspects of the bio-ecology of the vectors and reservoirs of T. cruzi in relation to human populations resident near areas with large quantities of palm trees, in rural, peri-urban and urban collection environments, located in the Western Brazilian Amazon. Rhodnius pictipes and Didelphis marsupialis were respectively the most predominant vector and reservoir, with rates of 71% for R. pictipes and 96.5% for D. marsupialis. The vast majority of T. cruzi isolates clustered with TcI. The most prevalent haplotype was TcI COII1 (69.7%). Mauritia flexuosa and Attalea phalerata were the main ecological indicators of infestation by triatomines. Birds were the most common food source (27,71%). T. cruzi isolated from R. robustus has the haplotype HUM-13, previously detected in a chronic Chagas patient living in the same area. Our results demonstrate the relevance of this study, with the occurrence of elevated infection rates in animals, and suggest the importance of the Amazon zones where there is a risk of infection in humans.

Efeito da suplementação de suínos em terminação com diferentes associações entre minerais sobre o desempenho, as características de carcaça e a viabilidade econômica

RESUMO Objetivou-se, com este estudo, verificar a influência da suplementação com diferentes associações entre minerais orgânicos sobre o desempenho e as características de carcaça, bem como avaliar sua viabilidade econômica, para suínos em terminação. Foram utilizados 88 machos castrados, divididos entre quatro tratamentos: controle com dieta basal e suplementação com CrFe, MgSe e CrFeMgSe, durante os 28 dias que antecederam o abate. O delineamento experimental foi em blocos ao acaso, com parcela experimental representada por dois animais. Os animais suplementados com CrFeMgSe apresentaram piores índices de peso final, ganho de peso diário e consumo durante todo o período, com consequente redução no peso de carcaça, menor profundidade de lombo, área de olho-de-lombo e menor quantidade de carne magra na carcaça. Houve um aumento no custo da dieta para os grupos CrFe, MgSe e CrFeMgSe, respectivamente. O uso de cromo mais ferro e magnésio mais selênio, associados dois a dois, não altera os parâmetros de desempenho e as características de carcaça. A associação dos quatro minerais, no entanto, promove piora nessas características e aumenta o custo da dieta.

Intestinal alkaline phosphatase and sodium butyrate may be beneficial in attenuating LPS-induced intestinal inflammation

In this study, we evaluated the effect of intestinal alkaline phosphatase (IAP) and sodium butyrate (NaBu) on lipopolysaccharide (LPS)-induced intestinal inflammation. Intestinal alkaline phosphatase and RelA/p65 (NF-κB) gene expressions in porcine jejunum explants were evaluated following exposure to sodium butyrate (NaBu) and essential oil from Brazilian red pepper (EO), alone or in combination with NaBu, as well as exogenous IAP with or without LPS challenge. Five piglets weighing approximately 20 kg each were sacrificed, and their jejunum were extracted. The tissues were segmented into 10 parts, which were exposed to 10 treatments. Gene expressions of IAP and RelA/p65 (NF-κB) in jejunal explants were evaluated via RT-PCR. We found that EO, NaBu, and exogenous IAP were able to up-regulate endogenous IAP and enhance RelA/p65 (NF-κB) gene expression. However, only NaBu and exogenous IAP down-regulated LPS-induced inflammatory response via RelA/p65 (NF-κB). In conclusion, we demonstrated that exogenous IAP and NaBu may be beneficial in attenuating LPS-induced intestinal inflammation.

Effects of ractopamine and arginine dietary supplementation for sows on growth performance and carcass quality of their progenies

The objective of this study was to evaluate the effects of ractopamine (Rac) and Arg fed to pregnant sows from d 25 to 53 of gestation on fetal muscle development as well as the performance and carcass characteristics of the progeny. One hundred sows were divided into 4 treatments including a control diet, the control plus 1% Arg, the control plus 20 mg/kg Rac, and the control diet supplemented with both additives at the same levels as those used separately. During the farrowing process the data evaluated were the weight of placenta to calculate the placental efficiency and the number of piglets born alive, stillborn, and mummified. To evaluate the fiber number and area, 12 male piglets from each treatment were euthanized to harvest semitendinosus muscle. During the lactation, the preweaning mortality, weaned weights, and number of piglets weaned per litter were evaluated. After weaning, the pig performance was evaluated until the slaughter following the sow treatment. At end of finishing phase, 1 male pig of each treatment replicate was selected to evaluation the carcass and pork quality. All variables measured were analyzed using the MIXED procedure of SAS and least squares means were compared using the Tukey test with P < 0.05. The control diet + supplementation of 1.0% of L-Arg + 20 mg/kg of ractopamine HCl from d 25 to 53 of gestation (Arg+Rac) treatment had a greater number of stillborn piglets (P = 0.014) than the control group. Piglet birth weights from sows fed Rac were 11% greater (P = 0.031) than those of piglets of the control treatment. The semitendinosus muscle fiber diameters of piglets at birth from sows that received Arg, Rac, and Arg+Rac were greater (P < 0.0001) than those of control piglets, and as consequence, the fiber number per square millimeter decreased (P < 0.0001). The final nursery BW of progeny from sows fed Arg and Rac individually were greater (P = 0.010) than those of progeny of the control group. At 110 d of age, in the beginning of the finisher 1 phase, pigs from Arg-fed sows were 1.9 kg heavier (P = 0.010) than pigs from the Arg+Rac-fed sows. The HCW were 2.97 and 1.64 kg heavier (P < 0.0001) for progeny of the Arg and Rac sows, respectively, compared with those of progeny of the control. In conclusion, the trial showed that the use of Rac for gestating sows increased the piglets' weight at birth. The size of muscular fiber was increased in the semitendinosus muscle of piglets originating from sows receiving Rac or Arg. However, the combination of both compounds did not have an additive effect in comparison with the control treatment but increased the stillbirth number.

Intestinal Alkaline Phosphatase: Potential Roles in Promoting Gut Health in Weanling Piglets and Its Modulation by Feed Additives - A Review

The intestinal environment plays a critical role in maintaining swine health. Many factors such as diet, microbiota, and host intestinal immune response influence the intestinal environment. Intestinal alkaline phosphatase (IAP) is an important apical brush border enzyme that is influenced by these factors. IAP dephosphorylates bacterial lipopolysaccharides (LPS), unmethylated cytosine-guanosine dinucleotides, and flagellin, reducing bacterial toxicity and consequently regulating toll-like receptors (TLRs) activation and inflammation. It also desphosphorylates extracellular nucleotides such as uridine diphosphate and adenosine triphosphate, consequently reducing inflammation, modulating, and preserving the homeostasis of the intestinal microbiota. The apical localization of IAP on the epithelial surface reveals its role on LPS (from luminal bacteria) detoxification. As the expression of IAP is reported to be downregulated in piglets at weaning, LPS from commensal and pathogenic gram-negative bacteria could increase inflammatory processes by TLR-4 activation, increasing diarrhea events during this phase. Although some studies had reported potential IAP roles to promote gut health, investigations about exogenous IAP effects or feed additives modulating IAP expression and activity yet are necessary. However, we discussed in this paper that the critical assessment reported can suggest that exogenous IAP or feed additives that could increase its expression could show beneficial effects to reduce diarrhea events during the post weaning phase. Therefore, the main goals of this review are to discuss IAP’s role in intestinal inflammatory processes and present feed additives used as growth promoters that may modulate IAP expression and activity to promote gut health in piglets.

Landscape structure in the Pirapó, Paranapanema 3 and 4 Hydrographic Unit, in the state of Paraná, Brazil

The aim of this study is to characterize the Pirapó, Paranapanema 3 and 4 Hydrographic Unit, emphasizing its physical attributes and processes of use and occupation, responsible for the structure of the current landscape and the state of its water resources. The recognition of the landscape's spatial structure in the hydrographic unit and its drainage basins was obtained by integrated analysis of the main elements that compose it: geology, landforms (hypsometric and slope), soils, climate and land use. Analysis revealed that within each drainage basin several variations in the spatial structure of the landscape occur which produce an internal compartmentalization. Each compartment is defined by its own geo-ecological structure, physiognomic standards and dynamics, reflected in its potentialities and vulnerabilities and in the conditions of water resources in the wake of occupation and use over time.

Audiometric Outcome Comparison between Titanium Prosthesis and Molded Autologous Material

Objective

To evaluate and compare the audiometric outcomes of ossicular reconstruction with titanium prosthesis and autologous material.

Study Design

Retrospective cohort study.

Setting

Tertiary referral center.

Subjects and Methods

Audiometric results of consecutive patients who performed ossiculoplasty with titanium prosthesis (n = 43) or autologous material (n = 48), from October 2008 to December 2011, were reviewed retrospectively and compared. The association between air-bone gain and age, ossiculoplasty material (autologous or titanium), preoperative diagnosis (chronic otitis media without cholesteatoma, cholesteatoma, or conductive hearing loss with intact tympanic membrane), and type of surgery (tympanoplasty, canal wall-down mastoidectomy, or canal wall-up mastoidectomy) was explored using regression analysis.

Results

Preoperative audiometric evaluation did not show differences between titanium and autologous groups in air-bone gap and pure-tone average. A postoperative decrease of 11.0 dB in air-bone gap and 12.4 dB in pure-tone average was observed in titanium ossiculoplasty compared with a reduction of 4.0 dB in air-bone gap and 5.1 dB in pure-tone average when autologous reconstruction was used. Mann-Whitney test revealed superior results in the titanium group compared with autologous reconstruction patients in air-bone gap ( P = .02) and pure-tone average ( P = .02). However, no statistically significant associations were observed after multivariate linear regression analysis of air-bone gap gain when adjusted for age, ossiculoplasty material, type of surgery, and preoperative diagnosis. One titanium prosthesis extrusion occurred during follow-up (2%).

Conclusion

Audiometric results achieved by titanium prosthesis are promising, but significant differences compared with autologous ossiculoplasty were not present.

Plasmodium yoelii: the effect of second blood meal and anti-sporozoite antibodies on development and gene expression in the mosquito vector, Anopheles stephensi

The sporogonic development of the malaria parasite takes place in the mosquito and a wide range of factors modulates it. Among those, the contents of the blood meal can influence the parasite development directly or indirectly through the mosquito response to the infection. We have studied the effect of a second blood meal in previously infected mosquitoes and the effect of anti-sporozoite immune serum on parasite development and mosquito response to the infection. The prevalence and intensity of infection and gene expression of both Plasmodium yoelii and Anopheles stephensi was analyzed. We verified that a second blood meal and its immune status interfere with parasite development and with Plasmodium and mosquito gene expression.

Effect of antibodies on the expression of Plasmodium falciparum circumsporozoite protein gene

Antibodies are known to play an important role in the control of malaria infection. However, they can modulate parasite development enhancing infection. The effect of anti-Plasmodium antibodies on the expression of circumsporozoite protein gene (csp) was investigated. Plasmodium falciparum 3D7 in vitro cultures were submitted to: i) anti- circumsporozoite protein monoclonal antibody (anti-CSP-mAb) [1microg/ml, 0.1microg/ml, 0.01microg/ml and 0.001microg/ml] and ii) purified IgG Fab fragment from a pool of malaria patients [1mg/ml and 1microg/ml]; and compared to control cultures. After 24h the number of ring infected erythrocytes was determined in order to calculate invasion efficacy. At 48h culture supernatant was collected, and the amount of circumsporozoite protein determined by ELISA, parasitaemia was calculated and cells were processed for RNA preparation. Expression of csp gene was quantified using Real time RT-PCR. There was an increase in parasite growth when treated with lower anti-CSP-mAb concentration, which was associated with lower csp expression, while 1mug/ml anti-CSP-mAb treatment presented a growth inhibitory effect accompanied by high csp expression.

Effect of chloroquine on the expression of genes involved in the mosquito immune response to Plasmodium infection

Chloroquine has been described to increase Plasmodium infectivity to the mosquito vector and is known to affect the vertebrate host immune response including during malarial infection. Although knowledge of the mosquito immune response has recently improved, nothing is known about the impact of chloroquine on mosquito immunity. In order to characterize the influence of chloroquine on the mosquito immune system, we have analyzed the effect of chloroquine on Anopheles gambiae (i) serine proteases and (ii) antimicrobial peptide gene expression, in uninfected and Plasmodium berghei infected mosquitoes, using real-time PCR. We have demonstrated for the first time that mosquitoes fed on chloroquine-treated mice showed a significant down regulation of some immune-related genes. This effect was independent of midgut bacterial burden. These results suggest that chloroquine might act on the Anopheles serine proteases cascade, interfering with signal transduction pathways and at a transcriptional activation level.

Tonsillectomy: cold dissection versus bipolar electrodissection

OBJECTIVES

to compare the technique and post-operative morbidity of two different tonsillectomy methods: cold dissection and bipolar electrodissection.

MATERIAL AND METHODS

prospective study including children (3> age <14) undergoing tonsillectomy in ORL Department of the main hospital in Azores, Portugal, from September 2000 to March 2001. Patients alternately selected to cold dissection tonsillectomy group (CDT) or bipolar electrodissection tonsillectomy group (BET). Duration of surgery; amount of blood loss; duration of hospitalization; aspect of tonsillar fossa on 10th post-operative day and intensity of pain after surgery were recorded and compared.

RESULTS

Sixty tonsillectomies were performed. Blood loss and duration of surgery were significantly decreased in BET group (P<0.001), but the healing process, directly assessed by the aspect of tonsillar fossa on the 10th day was markedly delayed. The intensity of pain was slightly higher in the BET group compared with the CDT group, and no difference on duration of hospitalization was found between the two groups. Two post-operative hemorrhages occurred (one in each group), and no major complications were registered.

CONCLUSIONS

BET reduces the duration of surgery and amount of blood loss when compared with cold dissection, but post-operative morbidity is increased. We believe the best patient indication for this method are small children where total circulating blood volume is reduced and patients with bleeding disorders.

Single strand conformational polymorphism evaluation for the identification of TH3R alleles of the circumsporozoite protein gene of Plasmodium falciparum

Highly polymorphic regions of the circumsporozoite protein (CSP) of Plasmodium falciparum are associated with cellular immune responses. One of these regions, the TH3R polymorfic region of the csp gene codes for known T-cell epitopes. The present study tested the use of SSCP to determine sequence variations of the TH3R regions of four clones of P. falciparum (3D7, HB3, Dd2 and K1) which are known to have different TH3R regions. Single-strand conformation polymorphism (SSCP) technique was performed on amplified products labelled with fluorescent primer (both strands) and electrophoresed in an automated sequencer. Various gel compositions and electrophoresis conditions were tested. Even if some electrophoretogram differences were observed between clones, they could not distinguish between the alleles.

Acute mastoiditis in children: review of the current status

BACKGROUND

acute mastoiditis is the most common intratemporal complication of otitis media. Its management is still a challenge due to potentially serious consequences. This study was designed to evaluate the recent experience with pediatric acute mastoiditis at our institution and to determine if the incidence of this entity is changing over time.

MATERIAL AND METHODS

retrospective review of records of children with acute mastoiditis treated at the hospital of the Medical School at the University of Porto, Portugal, between July 1993 and June 1998. Criteria for the diagnosis of acute mastoiditis were postauricular swelling and erythema, protrusion of the auricle, and evidence of co-existent or recent otitis media.

RESULTS

43 patients fulfilled the entry criteria. Most were boys (69%). Ages ranged from 8 months to 14 years and 4 months; infants represented 40% of the total. Acute mastoiditis was the first recognized sign of otitis media in 48% of patients. More recent years of the study saw an increase in the number of children referred with acute mastoiditis. Upon admission, 56% were under antibiotic treatment, with an average intake of 5.8 days. All patients were hospitalized; 26 cases recovered after intravenous antibiotics plus myringotomy, and the rest required an additional surgical procedure. The most common organisms recovered from cultures were Streptococcus pneumoniae and Streptococcus pyogenes. In our series, associated complications occurred in 13.9%; facial paralysis in one, and involvement of the central nervous system in five.

CONCLUSIONS

pediatric acute mastoiditis continues to be a potentially dangerous infection in the antibiotic era. The incidence of this complication may be increasing recently in the community studied. Great care is required of clinicians to reach an early diagnosis in order to promote adequate management and prevent inherently severe complications.

High-throughput sequence typing of T-cell epitope polymorphisms in Plasmodium falciparum circumsporozoite protein

We report a method for typing polymorphisms at the T-cell epitopes within the Th2R and Th3R regions of the Plasmodium falciparum circumsporozoite protein (CSP). This method combines the use of PCR and sequence specific oligonucleotide probes (PCR-SSOP), and allows the identification of single nucleotide polymorphisms in these epitope regions. PCR-SSOP is a robust and a high-throughput sequence typing technique which has the same specificity and fidelity as direct sequencing. This method has been developed specifically for the assessment of the protective efficacy of RTS,S/SBAS2 vaccine against the 3D7 strain of P. falciparum (RTS,S/SBAS2 vaccine contains a part of the 3D7 CSP protein) in a phase IIb trial in Gambia which has been completed recently. PCR-SSOP could be used to determine the allelic frequencies of other parasite antigens and their geographical distribution.

The effect of chloroquine on the production of interferon-gamma, interleukin (IL)-4, IL-6, and IL-10 in Plasmodium chabaudi chabaudi in infected C57BL6 mice

The effect of chloroquine (CQ) on the production pattern of interferon (IFN)-gamma, interleukin (IL)-4, IL-6, and IL-10 in female C57BL6 mice infected with Plasmodium chabaudi chabaudi AS was evaluated during a period of 35 days. Our data confirm that there is a switch from a T helper cell (Th)1 to a Th2 response during malaria infection in this model. Proliferation assays showed a decreased stimulation index in infected mice that was further reduced in infected mice treated with CQ. Noninfected control mice treated with CQ showed an increase production of IFN-gamma. However, no detectable changes in IL-4, IL-6, and IL-10 production were observed in this group. CQ treatment of infected mice resulted in parasite clearance that was associated with an earlier production of IL-4, IL-6, and IL-10 when compared with nontreated infected mice. We suggest that this earlier switch to a Th2 response is a consequence of parasite killing rather than CQ interference with cytokine production.

Cell-mediated immune responses to mycobacterial antigens in patients with pulmonary tuberculosis and HIV infection

Lymphocyte proliferation and cytokine responses induced by a panel of mycobacterial antigens were compared in Portuguese donors with pulmonary tuberculosis (TB) with or without HIV co-infection, HIV+ patients and healthy Mantoux-positive controls. Control donors showed stronger proliferative responses than any of the patient groups, with secreted antigens (Mycobacterium tuberculosis (Mtb) 30 kD and short-term culture filtrate proteins (ST-CFP)), purified protein derivative (PPD) and Mtb H37Rv Sonicate (MtbS) inducing the strongest proliferation. Patients with pulmonary TB showed lower proliferation to PPD or to the 30-kD antigen. Responses to all the antigens (PPD, ST-CFP, MtbS, 70 kD, 65 kD, 38 kD, 30 kD and 10 kD) were higher in TB/HIV patients with CD4 counts > or = 200 CD4+ T cells/mm3 compared with HIV alone (CD4 > or = 200 T cells/mm3), but were lost in both TB/HIV and HIV patients when CD4 counts fell below 200 T cells/mm3. Measurements of interferon-gamma (IFN-gamma) in culture supernatants revealed that PPD, 30 kD, MtbS and ST-CFP induced the strongest Th1 response. Analysis of mRNA for IFN-gamma, IL-4 and IL-10 confirmed that IFN-gamma production was maintained in patients with pulmonary TB without any concomitant increase in IL-4 or IL-10 mRNA expression, although expression of IL-10 mRNA was increased if HIV infection was present. These results reveal that IFN-gamma production is retained in pulmonary TB patients to a broad range of mycobacterial antigens, and that no switch to IL-4 production is seen even with HIV infection. Secreted antigens, and in particular ST-CFP, were the best inducers of IFN-gamma secretion, confirming their role in protective responses to Mtb.

Vittaforma corneae n. comb. for the human microsporidium Nosema corneum Shadduck, Meccoli, Davis & Font, 1990, based on its ultrastructure in the liver of experimentally infected athymic mice

A new genus, Vittaforma n.g. is proposed for the human microsporidium Nosema corneum Shadduck, Meccoli, Davis & Font, 1990, based on the ultrastructure of developmental stages in the liver of experimentally infected athymic mice. The diplokaryotic arrangement of the nuclei is the only character that conforms with the description of the genus Nosema. Sporogony is polysporoblastic, sporonts are ribbon-shaped, constricting to give rise to linear arrays of sporoblasts and each parasite is enveloped by a complete cisterna of host endoplasmic reticulum. Comparison of N. corneum, with established genera revealed that there were none with the same combination of characters. Consequently it is proposed that Nosema corneum be placed in a new genus as Vittaforma corneae n. comb.

Experimental infection of athymic mice with the human microsporidian Nosema corneum

Athymic mice (BALB/c nu/nu/Ola/Hsd) were experimentally infected intraperitoneally with Nosema corneum spores. Infection was monitored in the first and second weeks post-infection. The liver, spleen, kidney, intestine, lung, heart, brain and eye were collected. Quantification of infection in each organ using three different techniques gave approximately the same pattern of infection. Infection increased with time. Histological observations were made on the sites of infection in each organ. All organs were infected, the liver being the most heavily infected. The eye was infected in the retina in contrast to the cornea which was the site of infection in the original host. The present study of N. corneum in athymic mice has shown that this system could also be used to study host-parasite relationships and serve as a model for testing therapeutic agents. Previously the only microsporidian serving as a suitable model for human microsporidiosis was Encephalitozoon cuniculi.