Signatures of aestivation and migration in Sahelian malaria mosquito populations.

During the long Sahelian dry season, mosquito vectors of malaria are expected to perish when no larval sites are available; yet, days after the first rains, mosquitoes reappear in large numbers. How these vectors persist over the 3-6-month long dry season has not been resolved, despite extensive research for over a century. Hypotheses for vector persistence include dry-season diapause (aestivation) and long-distance migration (LDM); both are facets of vector biology that have been highly controversial owing to lack of concrete evidence. Here we show that certain species persist by a form of aestivation, while others engage in LDM. Using time-series analyses, the seasonal cycles of Anopheles coluzzii, Anopheles gambiae sensu stricto (s.s.), and Anopheles arabiensis were estimated, and their effects were found to be significant, stable and highly species-specific. Contrary to all expectations, the most complex dynamics occurred during the dry season, when the density of A. coluzzii fluctuated markedly, peaking when migration would seem highly unlikely, whereas A. gambiae s.s. was undetected. The population growth of A. coluzzii followed the first rains closely, consistent with aestivation, whereas the growth phase of both A. gambiae s.s. and A. arabiensis lagged by two months. Such a delay is incompatible with local persistence, but fits LDM. Surviving the long dry season in situ allows A. coluzzii to predominate and form the primary force of malaria transmission. Our results reveal profound ecological divergence between A. coluzzii and A. gambiae s.s., whose standing as distinct species has been challenged, and suggest that climate is one of the selective pressures that led to their speciation. Incorporating vector dormancy and LDM is key to predicting shifts in the range of malaria due to global climate change, and to the elimination of malaria from Africa.

Seasonal variation in spatial distributions of Anopheles gambiae in a Sahelian village: evidence for aestivation.

Changes in spatial distribution of mosquitoes over time in a Sahelian village were studied to understand the sources of the mosquitoes during the dry season when no larval sites are found. At that time, the sources of Anopheles gambiae Giles may be local shelters used by aestivating mosquitoes or migrants from distant populations. The mosquito distribution was more aggregated during the dry season, when few houses had densities 7- to 24-fold higher than expected. The high-density houses during the dry season differed from those of the wet season. Most high-density houses during the dry season changed between years, yet their vicinity was rather stable. Scan statistics confirmed the presence of one or two adjacent hotspots in the dry season, usually found on one edge of the village. These hotspots shifted between the early and late dry season. During the wet season, the hotspots were relatively stable near the main larval site. The locations of the hotspots in the wet season and early and late dry season were similar between years. Season-specific, stable, and focal hotspots are inconsistent with the predictions based on the arrival of migrants from distant localities during the dry season, but are consistent with the predictions based on local shelters used by aestivating mosquitoes. Targeting hotspots in Sahelian villages for vector control may not be effective because the degree of aggregation is moderate, the hotspots are not easily predicted, and they are not the sources of the population. However, targeting the dry-season shelters may be highly cost-effective, once they can be identified and predicted.

Virtual hospital-level care-feasibility, acceptability, safety and impact of a pilot Hospital-In-The-Home model for COVID-19 infection.

Background: Hospital-in-the-Home (HITH) delivers hospital level care to patients in the comfort of their own home. Traditionally HITH involves clinicians travelling to patients' homes. We designed and implemented a virtual model of care leveraging a combination of virtual health modalities for children with COVID-19 in response to rising patient numbers, infection risk and pressures on protective equipment. In contrast to other models for COVID-19 infection in Australia at the time, our HITH service catered only for children who were unwell enough to meet criteria for hospitalisation (ie bed-replacement). Aims: To measure the feasibility, acceptability, safety and impact of a virtual model of care for managing children with COVID-19 infection requiring hospital-level care. Methods: Retrospective study of a new virtual model of care for all children admitted to the Royal Children's HITH service with COVID-19 infection between 7th October 2021 and 28th April 2022. The model consisted of at least daily video consultations, remote oximetry, symptom tracking, portal messaging and 24 h phone and video support. Patients were eligible if they met a certain level of severity (work of breathing, dehydration, lower oxygen saturations) without requiring intravenous fluids, oxygen support or intensive care. Online surveys were distributed to staff and consumers who experienced the model of care. Results: 331 patients were managed through the virtual HITH program with a mean length of stay of 3.5 days. Of these, 331 (100%) engaged in video consultations, 192 (58%) engaged in the patient portal and completed the symptom tracker a total of 634 times and communicated via a total of 783 messages. Consumer satisfaction (n = 31) was high (4.7/5) with the most useful aspect of the model rated as video consultation. Clinician satisfaction (n = 9) was also high with a net promoter score of 8.9. There were no adverse events at home. Eight children (2.4%) represented to hospital, 7 (2.1%) of whom were readmitted. The impact is represented by a total of 1,312 hospital bed-days saved in the seven-month period (2,249 bed-days per year). In addition, 1,480 home visits (travel time/ protective equipment/ infection risk) were avoided. Conclusion: A virtual HITH program for COVID-19 in children is feasible, acceptable and safe and has a substantial impact on bed-days saved and nursing travel time. The implications for management of other acute respiratory viral illnesses that contribute to hospital bed pressure during winter months is immense. Virtual HITH is likely to be a key enabler of a sustainable healthcare system.

Lung adenocarcinoma with thyroid metastasis: a case report.

BACKGROUND: The metastases of a primary lung cancer over the thyroid gland are extremely rare. We report on an unusual presentation of thyroid metastasis of lung cancer in order to improve the management of similar cases. CASE PRESENTATION: Three years ago, a Moroccan male 59-year-old was admitted for dyspnea, dry cough, and chest pain. He had smoked about 30 cigarette packs a year. Clinical examination revealed a right thyroid nodule. Chest and neck computed tomography (CT) scan showed a proximal left tumor in contact with the pulmonary artery and revealed a suspected nodule in the right lobe of the thyroid with homolateral neck node. Transbronchial biopsy was performed and pathological examination revealed adenocarcinoma of the lung and positive for thyroid transcription factor. Other explorations carried out, such as brain CT, bone scan and abdominal ultrasound were normal. After a repeated negative fine needle aspiration biopsy of the suspected nodule of the right lobe of the thyroid, we performed total thyroidectomy with neck dissection. An anatomopathologic exam revealed a tubulopapillary adenocarcinoma poorly differentiated. An Immunohistochemistry showed positive tumor cells with TTF1 and cytokeratin (CK) 7 but negative cells with thyroglobulin and CK20. Thus, the pulmonary tumor was classified stage IV. Chemotherapy based on the combination of cisplatin and etoposide was conducted along with supportive care. The tumor grew up with brain metastases after three cycles of chemotherapy. Unfortunately, the patient died 2 months after despite brain radiotherapy. CONCLUSION: We presented a medical case of a patient with thyroid metastasis resulting from a pulmonary adenocarcinoma which has rapidly evolved to brain metastases. The prognosis was pejorative in our clinical case (5 months after admission).

Molecular epidemiology of noroviruses detected in Vietnamese children with acute gastroenteritis from 2012 to 2015.

Noroviruses, an important cause of diarrhoea in humans, are genetically diverse. The recent norovirus seasons recorded the emergence of new recombinants of the capsid and polymerase genotypes, with a global dominance of GII.Pe_GII.4 Sydney 2012 and GII.P17_GII.17 in Asian countries. However, the number of papers reporting the distribution of both polymerase and capsid genotypes circulating among children is scarce, with none from Vietnam. This study described both the polymerase and capsid genotypes of noroviruses circulating in Vietnamese children using stool specimens obtained under the World Health Organization rotavirus surveillance programme from 2012 to 2015. Of 350 specimens tested, noroviruses were detected in 90 (28 %) of 319 inpatient specimens and in 9 (29 %) of 31 outpatient specimens. The polymerase and capsid genotype combinations of GII.Pe_GII.4 Sydney 2012 and GII.P21_GII.3 were co-dominant (51 and 24 %, respectively), both of which were recombinants, contributing to a high proportion (87 %) of recombinants among circulating noroviruses. GII.4 variants evolved in the same fashion in Vietnam as in other countries, with amino acid substitutions in the putative variant-specific epitopes of the protruding domain. Unlike neighbouring countries where the predominance of GII.P17_GII.17 was reported, only one GII.P17_GII.17 strain was detected from an outpatient in 2015 in Vietnam. In conclusion, a substantial burden due to norovirus gastroenteritis hospitalizations among Vietnamese children was associated with circulating co-dominant GII.Pe_GII.4 Sydney 2012 and GII.P21_GII.3 strains. Continued surveillance is necessary to monitor infection caused by GII.4 variants and that of GII.P17_GII.17 noroviruses in paediatric patients in Vietnam.

Reproductive output of female Anopheles gambiae (Diptera: Culicidae): comparison of molecular forms.

Knowledge of ecological differences between the molecular forms of Anopheles gambiae Giles (Diptera: Culicidae) might lead to understanding of their unique contribution to disease transmission, to better vector control, and to identification of the forces that have separated them. We compared female fecundity measured as egg batch size in relation to body size between the molecular forms in Mali and contrasted them with their sibling species, Anopheles arabiensis Patton. To determine whether eggs of different egg batches are of similar "quality," we compared the total protein content of first-stage larvae (L1s), collected < 2 h after hatching in deionized water. Egg batch size significantly varied between An. gambiae and An. arabiensis and between the molecular forms of An. gambiae (mean batch size was 186.3, 182.5, and 162.0 eggs in An. arabiensis and the M and the S molecular form of An. gambiae, respectively). After accommodating female body size, however, the difference in batch size was not significant. In the S molecular form, egg protein content was not correlated with egg batch size (r = -0.08, P > 0.7) nor with female body size (r = -0.18, P > 0.4), suggesting that females with more resources invest in more eggs rather than in higher quality eggs. The mean total protein in eggs of the M form (0.407 microg per L1) was 6% higher than that of the S form (0.384 microg per L1), indicating that the M form invests a greater portion of her resources into current (rather than future) reproduction. A greater investment per offspring coupled with larger egg batch size may reflect an adaptation of the M form to low productivity larval sites as independent evidence suggests.

[Therapeutic outcomes of medulloblastoma in Casablanca from 2000 to 2012]. / Résultats du traitement du médulloblastome à Casablanca de 2000 à 2012.

PURPOSE: To describe the therapeutic results, with the aim to contribute to improving the care of patients with medulloblastoma. PATIENTS AND METHODS: A retrospective study of 69 cases of medulloblastoma collected in the university hospital Ibn Rochd of Casablanca between 2000 and 2012. RESULTS: Fifty-three children with an average age of 9 years and 16 adults with an average age of 32.4 years were included in the study. Thirty-seven children and eight adults suffered from a high-risk tumour. The radiotherapy was received by all patients with a mean dose of 36 Gy to the whole brain and 54 Gy in the posterior fossa. All patients in the paediatric group and 10 patients in the adult group received concomitant chemotherapy, 44 children and four adults received adjuvant chemotherapy. Tumour recurrence was observed in 17 children after a mean follow-up period of 38 months. These recurrences were observed in five adults after a mean follow-up period of 42 months. The posterior fossa was the main site of relapses. Overall survival was 77.7% for the children and 61% for the adults. Overall survival was better (70% versus 25%) when the interval between radiotherapy and surgery was less than 40 days in the paediatric group. The recurrence rate was significantly higher for the high-risk group: 41% versus 13% for the standard risk. In the adult group, overall survival differences according to the risk group were significant (100% for the standard risk versus 37.5% for the high risk). CONCLUSION: The overall survival and recurrences rate obtained are encouraging. The risk group and time between surgery and radiotherapy were prognostic factors with significant impact on survival depending on the age group. We recommend reducing these times to improve therapeutic results.

Successful reinfection of chronically infected mice by a different Toxoplasma gondii genotype.

It is generally assumed that primary infection by Toxoplasma gondii protects from reinfection. A recent study using a murine model has questioned this dogma using indirect procedures to detect the reinfecting strain. We have reinvestigated this issue using a transfected strain of T. gondii (Prugniaud beta galactosidase: Pru beta gal) which expresses Escherichia coli beta-galactosidase. Detection of enzyme activity on fixed parasites allows a direct distinction between transfected and untransfected strains. We have found that in OF1 mice primary infection with the 76 K strain of T. gondii fully protects mice against tissue cyst production upon reinfection with the Pru beta gal T. gondii strain whereas primary infection with the Pru beta gal T. gondii strain does not impair tissue cyst formation upon reinfection with the Ned strain of T. gondii, which belongs to another T. gondii genotype. These results suggest that the immune protection conferred by one strain of T. gondii can be breached by reinfection with a strain belonging to another genotype; which can have significant consequences in human or veterinary medicine.

Human tails and pseudotails.

A case of a tail in a 2-week-old infant is reported, and findings from a review of 33 previously reported cases of true tails and pseudotails are summarized. The true, or persistent, vestigial tail of humans arises from the most distal remnant of the embryonic tail. It contains adipose and connective tissue, central bundles of striated muscle, blood vessels, and nerves and is covered by skin. Bone, cartilage, notochord, and spinal cord are lacking. The true tail arises by retention of structures found normally in fetal development. It may be as long as 13 cm, can move and contract, and occurs twice as often in males as in females. A true tail is easily removed surgically, without residual effects. It is rarely familial. Pseudotails are varied lesions having in common a lumbosacral protrusion and a superficial resemblance to persistent vestigial tails. The most frequent cause of a pseudotail in a series of ten cases obtained from the literature was an anomalous prolongation of the coccygeal vertebrae. Additional lesions included two lipomas, and one each of teratoma, chondromegaly , glioma, and a thin, elongated parasitic fetus.

Trabecular carcinoma of the skin: a case report.

A case of trabecular carcinoma of the skin in a 62 year old Caucasian male is reported. The lesions occurred on the face, ear, chest, abdominal wall, and the upper extremity over a period of four years. At the light microscopic level the lesions were confused with metastatic carcinoma, lymphoma, and adult neuroblastoma. Ultrastructural study revealed the presence of not only neurosecretory granules but also premelanosomes in the tumor cells.

Complete recovery from Cryptosporidium parvum infection with gastroenteritis and sclerosing cholangitis after successful bone marrow transplantation in two brothers with X-linked hyper-IgM syndrome.

We describe two brothers who suffered from hyper-IgM syndrome (HIGM1) with similar clinical features: recurrent infections, especially cryptosporidium gastroenteritis with cholangitis. Their activated T cells did not express CD40L. Nucleotide sequencing revealed a mutation in both boys with respect to intron 4 and exon 5 boundaries of the CD40L gene in Xq26. They underwent successful bone marrow transplantation (BMT) from HLA-geno-identical siblings. The Cryptosporidium infection and cholangitis resolved thereafter. At 6 months after BMT, expression of CD40L on activated T lymphocytes was normal. After 1 year, both boys are well, and immune reconstitution has improved. Based on these two successful experiences, BMT with a genoidentical sibling seems a reasonable therapeutic approach for HIGM1, if Cryptosporidium infection occurs.

Frequency of Entamoeba gingivalis in human gingival scrapings.

A survey was made of gingival scrapings stained by the Papanicolaou method to assess the occurrence of Entamoeba gingivalis, a nonpathogenic-oral amoeba. Positive findings were recorded in 59% of 113 dental patients, and 32% of 96 healthy controls. These figures showed no significant changes during the last 20 years when compared with data published in 1960 and 1963. The existence of E. gingivalis and its rare appearance in the sputum should be known to cytologists because of the morphologic resemblance to Entamoeba histolytica, a pathogenic amoeba. Morphologic features are described to differentiate E. gingivalis from similar structures found in sputum.

Chorioangioma of the placenta: report of 2 cases with ultrasound study in 1.

Chorioangioma, a benign tumor of the placenta, is often associated with unfavorable effects on the mother as well as on the fetus. Two recently recorded cases of large chorioangiomas occurring in young mothers are reported. In 1 case, in which hydramnios was identified and the fetus was prematurely delivered, the diagnosis of placental tumor was made by ultrasound study.

Serum beta-human chorionic gonadotropin levels relate poorly with the size of a tubal pregnancy.

Ectopic implantation usually begins with relatively normal growth of trophoblast and serum beta-hCG progression. However, the trophoblast eventually erodes into vessels and a variable degree of bleeding and hematoma compromises its growth. The serum beta-hCG level then usually begins to demonstrate some degree of abnormal progression. For our patients, the length of the ectopic pregnancy varied widely, depending mainly on when the individual patient chose to seek medical treatment. Infertility patients followed from the moment of conception would thus be expected to show a better correlation between early beta-hCG levels and the size of the tubal pregnancy. Preconditions for the operative laparoscopic management of a tubal pregnancy usually include that the tube be unruptured, less than 3 cm in diameter, and readily accessible via the laparoscopic approach. Ackerman et al. suggested there was a general correlation between the serum beta-hCG level and tubal rupture, and the present data demonstrate an overall positive correlation between the size of the tubal pregnancy and the serum level. However, the range of levels is so broad for any given size of mass or tubal status that this correlation is not meaningful clinically. A reliable method to determine the size and status of a tubal pregnancy before laparoscopy would be valuable. Unfortunately, we did not find the preoperative serum beta-hCG level to be useful for making this prediction.

Cutaneous metastatic adenocarcinoma of gallbladder origin.

Cutaneous metastases developed in a 74-year-old woman from an adenocarcinoma of the gallbladder. A biopsy specimen of a cutaneous nodule showed the presence of systemic cancer. Results of a histopathologic examination, along with the autopsy findings, established that the cutaneous metastasis was of gallbladder origin. This article reports the extreme rarity of metastases from a cancer of the gallbladder to the skin.

Behavioural determinants of gene flow in malaria vector populations: Anopheles gambiae males select large females as mates.

BACKGROUND: Plasmodium-refractory mosquitoes are being rapidly developed for malaria control but will only succeed if they can successfully compete for mates when released into the wild. Pre-copulatory behavioural traits maintain genetic population structure in wild mosquito populations and mating barriers have foiled previous attempts to control malaria vectors through sterile male release. METHODS: Varying numbers of virgin male and female Anopheles gambiae Giles, from two strains of different innate sizes, were allowed to mate under standardized conditions in laboratory cages, following which, the insemination status, oviposition success and egg batch size of each female was assessed. The influence of male and female numbers, strain combination and female size were determined using logistic regression, correlation analysis and a simple mechanistic model of male competition for females. RESULTS: Male An. gambiae select females on the basis of size because of much greater fecundity among large females. Even under conditions where large numbers of males must compete for a smaller number of females, the largest females are more likely to become inseminated, to successfully oviposit and to produce large egg batches. CONCLUSIONS: Sexual selection, on the basis of size, could either promote or limit the spread of malaria-refractory genes into wild populations and needs to be considered in the continued development and eventual release of transgenic vectors. Fundamental studies of behavioural ecology in malaria vectors such as An. gambiae can have important implications for malaria control and should be prioritised for more extensive investigation in the future.